From aaccb4ff14347c32f8742997840fc5101a5b1a83 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Adam=20W=C3=B3js?= <adam@wojs.pl>
Date: Sat, 9 Nov 2019 13:27:22 +0100
Subject: [PATCH] EZP-31118: Introduced strict types for ContenteService

---
 .../Imagine/ImageAsset/AliasGeneratorTest.php |   4 +-
 eZ/Publish/API/Repository/ContentService.php  |  94 +++----
 eZ/Publish/Core/Event/ContentService.php      |  10 +-
 .../Content/Gateway/DoctrineDatabase.php      |   8 +-
 eZ/Publish/Core/Repository/ContentService.php | 263 ++++++++++--------
 eZ/Publish/Core/Repository/SearchService.php  |   3 +-
 .../SiteAccessAware/ContentService.php        |  76 ++---
 .../Tests/ContentServiceTest.php              |  81 +++---
 .../Tests/Service/Mock/ContentTest.php        | 249 +++++++++++------
 .../Tests/Service/Mock/SearchTest.php         |   7 +-
 eZ/Publish/Core/Repository/TrashService.php   |   4 +-
 eZ/Publish/Core/Repository/UserService.php    |  10 +-
 .../Decorator/ContentServiceDecorator.php     |  72 ++---
 .../Decorator/ContentServiceDecoratorTest.php |  57 ++--
 14 files changed, 530 insertions(+), 408 deletions(-)

diff --git a/eZ/Bundle/EzPublishCoreBundle/Tests/Imagine/ImageAsset/AliasGeneratorTest.php b/eZ/Bundle/EzPublishCoreBundle/Tests/Imagine/ImageAsset/AliasGeneratorTest.php
index cecc5e413a0..3a412c22026 100644
--- a/eZ/Bundle/EzPublishCoreBundle/Tests/Imagine/ImageAsset/AliasGeneratorTest.php
+++ b/eZ/Bundle/EzPublishCoreBundle/Tests/Imagine/ImageAsset/AliasGeneratorTest.php
@@ -49,9 +49,7 @@ protected function setUp(): void
     public function testGetVariationOfImageAsset()
     {
         $assetField = new Field([
-            'value' => new ImageAsset\Value([
-                'destinationContentId' => 486,
-            ]),
+            'value' => new ImageAsset\Value(486),
         ]);
         $imageField = new Field([
             'value' => new Image\Value([
diff --git a/eZ/Publish/API/Repository/ContentService.php b/eZ/Publish/API/Repository/ContentService.php
index 2da9bf963f5..ba36714c46c 100644
--- a/eZ/Publish/API/Repository/ContentService.php
+++ b/eZ/Publish/API/Repository/ContentService.php
@@ -1,11 +1,11 @@
 <?php
 
 /**
- * File containing the eZ\Publish\API\Repository\ContentService class.
- *
  * @copyright Copyright (C) eZ Systems AS. All rights reserved.
  * @license For full copyright and license information view LICENSE file distributed with this source code.
  */
+declare(strict_types=1);
+
 namespace eZ\Publish\API\Repository;
 
 use eZ\Publish\API\Repository\Values\Content\ContentDraftList;
@@ -15,15 +15,15 @@
 use eZ\Publish\API\Repository\Values\ContentType\ContentType;
 use eZ\Publish\API\Repository\Values\Content\ContentCreateStruct;
 use eZ\Publish\API\Repository\Values\Content\ContentMetadataUpdateStruct;
+use eZ\Publish\API\Repository\Values\Content\Content;
 use eZ\Publish\API\Repository\Values\Content\VersionInfo;
 use eZ\Publish\API\Repository\Values\Content\ContentInfo;
+use eZ\Publish\API\Repository\Values\Content\Relation;
 use eZ\Publish\API\Repository\Values\User\User;
 use eZ\Publish\API\Repository\Values\Content\LocationCreateStruct;
 
 /**
  * This class provides service methods for managing content.
- *
- * @example Examples/content.php
  */
 interface ContentService
 {
@@ -39,7 +39,7 @@ interface ContentService
      *
      * @return \eZ\Publish\API\Repository\Values\Content\ContentInfo
      */
-    public function loadContentInfo($contentId);
+    public function loadContentInfo(int $contentId): ContentInfo;
 
     /**
      * Bulk-load ContentInfo items by id's.
@@ -64,7 +64,7 @@ public function loadContentInfoList(array $contentIds): iterable;
      *
      * @return \eZ\Publish\API\Repository\Values\Content\ContentInfo
      */
-    public function loadContentInfoByRemoteId($remoteId);
+    public function loadContentInfoByRemoteId(string $remoteId): ContentInfo;
 
     /**
      * Loads a version info of the given content object.
@@ -75,11 +75,11 @@ public function loadContentInfoByRemoteId($remoteId);
      * @throws \eZ\Publish\API\Repository\Exceptions\UnauthorizedException if the user is not allowed to load this version
      *
      * @param \eZ\Publish\API\Repository\Values\Content\ContentInfo $contentInfo
-     * @param int $versionNo the version number. If not given the current version is returned.
+     * @param int|null $versionNo the version number. If not given the current version is returned.
      *
      * @return \eZ\Publish\API\Repository\Values\Content\VersionInfo
      */
-    public function loadVersionInfo(ContentInfo $contentInfo, $versionNo = null);
+    public function loadVersionInfo(ContentInfo $contentInfo, ?int $versionNo = null): VersionInfo;
 
     /**
      * Loads a version info of the given content object id.
@@ -89,12 +89,12 @@ public function loadVersionInfo(ContentInfo $contentInfo, $versionNo = null);
      * @throws \eZ\Publish\API\Repository\Exceptions\NotFoundException - if the version with the given number does not exist
      * @throws \eZ\Publish\API\Repository\Exceptions\UnauthorizedException if the user is not allowed to load this version
      *
-     * @param mixed $contentId
-     * @param int $versionNo the version number. If not given the current version is returned.
+     * @param int $contentId
+     * @param int|null $versionNo the version number. If not given the current version is returned.
      *
      * @return \eZ\Publish\API\Repository\Values\Content\VersionInfo
      */
-    public function loadVersionInfoById($contentId, $versionNo = null);
+    public function loadVersionInfoById(int $contentId, ?int $versionNo = null): VersionInfo;
 
     /**
      * Loads content in a version for the given content info object.
@@ -107,12 +107,12 @@ public function loadVersionInfoById($contentId, $versionNo = null);
      * @param \eZ\Publish\API\Repository\Values\Content\ContentInfo $contentInfo
      * @param array $languages A language priority, filters returned fields and is used as prioritized language code on
      *                         returned value object. If not given all languages are returned.
-     * @param int $versionNo the version number. If not given the current version is returned from $contentInfo
+     * @param int|null $versionNo the version number. If not given the current version is returned from $contentInfo
      * @param bool $useAlwaysAvailable Add Main language to \$languages if true (default) and if alwaysAvailable is true
      *
      * @return \eZ\Publish\API\Repository\Values\Content\Content
      */
-    public function loadContentByContentInfo(ContentInfo $contentInfo, array $languages = null, $versionNo = null, $useAlwaysAvailable = true);
+    public function loadContentByContentInfo(ContentInfo $contentInfo, array $languages = null, ?int $versionNo = null, bool $useAlwaysAvailable = true): Content;
 
     /**
      * Loads content in the version given by version info.
@@ -120,13 +120,13 @@ public function loadContentByContentInfo(ContentInfo $contentInfo, array $langua
      * @throws \eZ\Publish\API\Repository\Exceptions\UnauthorizedException if the user is not allowed to load this version
      *
      * @param \eZ\Publish\API\Repository\Values\Content\VersionInfo $versionInfo
-     * @param array $languages A language priority, filters returned fields and is used as prioritized language code on
+     * @param string[] $languages A language priority, filters returned fields and is used as prioritized language code on
      *                         returned value object. If not given all languages are returned.
      * @param bool $useAlwaysAvailable Add Main language to \$languages if true (default) and if alwaysAvailable is true
      *
      * @return \eZ\Publish\API\Repository\Values\Content\Content
      */
-    public function loadContentByVersionInfo(VersionInfo $versionInfo, array $languages = null, $useAlwaysAvailable = true);
+    public function loadContentByVersionInfo(VersionInfo $versionInfo, array $languages = null, bool $useAlwaysAvailable = true): Content;
 
     /**
      * Loads content in a version of the given content object.
@@ -137,14 +137,14 @@ public function loadContentByVersionInfo(VersionInfo $versionInfo, array $langua
      * @throws \eZ\Publish\API\Repository\Exceptions\UnauthorizedException If the user has no access to read content and in case of un-published content: read versions
      *
      * @param mixed $contentId
-     * @param array $languages A language priority, filters returned fields and is used as prioritized language code on
+     * @param string[] $languages A language priority, filters returned fields and is used as prioritized language code on
      *                         returned value object. If not given all languages are returned.
-     * @param int $versionNo the version number. If not given the current version is returned
+     * @param int|null $versionNo the version number. If not given the current version is returned
      * @param bool $useAlwaysAvailable Add Main language to \$languages if true (default) and if alwaysAvailable is true
      *
      * @return \eZ\Publish\API\Repository\Values\Content\Content
      */
-    public function loadContent($contentId, array $languages = null, $versionNo = null, $useAlwaysAvailable = true);
+    public function loadContent(int $contentId, array $languages = null, ?int $versionNo = null, bool $useAlwaysAvailable = true): Content;
 
     /**
      * Loads content in a version for the content object reference by the given remote id.
@@ -155,14 +155,14 @@ public function loadContent($contentId, array $languages = null, $versionNo = nu
      * @throws \eZ\Publish\API\Repository\Exceptions\UnauthorizedException If the user has no access to read content and in case of un-published content: read versions
      *
      * @param string $remoteId
-     * @param array $languages A language priority, filters returned fields and is used as prioritized language code on
+     * @param string[] $languages A language priority, filters returned fields and is used as prioritized language code on
      *                         returned value object. If not given all languages are returned.
-     * @param int $versionNo the version number. If not given the current version is returned
+     * @param int|null $versionNo the version number. If not given the current version is returned
      * @param bool $useAlwaysAvailable Add Main language to \$languages if true (default) and if alwaysAvailable is true
      *
      * @return \eZ\Publish\API\Repository\Values\Content\Content
      */
-    public function loadContentByRemoteId($remoteId, array $languages = null, $versionNo = null, $useAlwaysAvailable = true);
+    public function loadContentByRemoteId(string $remoteId, array $languages = null, ?int $versionNo = null, bool $useAlwaysAvailable = true): Content;
 
     /**
      * Bulk-load Content items by the list of ContentInfo Value Objects.
@@ -179,7 +179,7 @@ public function loadContentByRemoteId($remoteId, array $languages = null, $versi
      *
      * @return \eZ\Publish\API\Repository\Values\Content\Content[] list of Content items with Content Ids as keys
      */
-    public function loadContentListByContentInfo(array $contentInfoList, array $languages = [], $useAlwaysAvailable = true);
+    public function loadContentListByContentInfo(array $contentInfoList, array $languages = [], bool $useAlwaysAvailable = true): iterable;
 
     /**
      * Creates a new content draft assigned to the authenticated user.
@@ -203,7 +203,7 @@ public function loadContentListByContentInfo(array $contentInfoList, array $lang
      *
      * @return \eZ\Publish\API\Repository\Values\Content\Content - the newly created content draft
      */
-    public function createContent(ContentCreateStruct $contentCreateStruct, array $locationCreateStructs = []);
+    public function createContent(ContentCreateStruct $contentCreateStruct, array $locationCreateStructs = []): Content;
 
     /**
      * Updates the metadata.
@@ -218,7 +218,7 @@ public function createContent(ContentCreateStruct $contentCreateStruct, array $l
      *
      * @return \eZ\Publish\API\Repository\Values\Content\Content the content with the updated attributes
      */
-    public function updateContentMetadata(ContentInfo $contentInfo, ContentMetadataUpdateStruct $contentMetadataUpdateStruct);
+    public function updateContentMetadata(ContentInfo $contentInfo, ContentMetadataUpdateStruct $contentMetadataUpdateStruct): Content;
 
     /**
      * Deletes a content object including all its versions and locations including their subtrees.
@@ -227,9 +227,9 @@ public function updateContentMetadata(ContentInfo $contentInfo, ContentMetadataU
      *
      * @param \eZ\Publish\API\Repository\Values\Content\ContentInfo $contentInfo
      *
-     * @return mixed[] Affected Location Id's (List of Locations of the Content that was deleted)
+     * @return int[] Affected Location Id's (List of Locations of the Content that was deleted)
      */
-    public function deleteContent(ContentInfo $contentInfo);
+    public function deleteContent(ContentInfo $contentInfo): iterable;
 
     /**
      * Creates a draft from a published or archived version.
@@ -241,18 +241,18 @@ public function deleteContent(ContentInfo $contentInfo);
      * @throws \eZ\Publish\API\Repository\Exceptions\UnauthorizedException if the current-user is not allowed to create the draft
      *
      * @param \eZ\Publish\API\Repository\Values\Content\ContentInfo $contentInfo
-     * @param \eZ\Publish\API\Repository\Values\Content\VersionInfo $versionInfo
-     * @param \eZ\Publish\API\Repository\Values\User\User $creator Used as creator of the draft if given - otherwise uses current-user
+     * @param \eZ\Publish\API\Repository\Values\Content\VersionInfo|null $versionInfo
+     * @param \eZ\Publish\API\Repository\Values\User\User|null $creator Used as creator of the draft if given - otherwise uses current-user
      * @param \eZ\Publish\API\Repository\Values\Content\Language|null if not set the draft is created with the initialLanguage code of the source version or if not present with the main language.
      *
      * @return \eZ\Publish\API\Repository\Values\Content\Content - the newly created content draft
      */
     public function createContentDraft(
         ContentInfo $contentInfo,
-        VersionInfo $versionInfo = null,
-        User $creator = null,
+        ?VersionInfo $versionInfo = null,
+        ?User $creator = null,
         ?Language $language = null
-    );
+    ): Content;
 
     /**
      * Counts drafts for a user.
@@ -280,7 +280,7 @@ public function countContentDrafts(?User $user = null): int;
      *
      * @return \eZ\Publish\API\Repository\Values\Content\VersionInfo[] the drafts ({@link VersionInfo}) owned by the given user
      */
-    public function loadContentDrafts(User $user = null);
+    public function loadContentDrafts(?User $user = null): iterable;
 
     /**
      * Loads drafts for a user when content is not in the trash. The list is sorted by modification date.
@@ -311,7 +311,7 @@ public function loadContentDraftList(?User $user = null, int $offset = 0, int $l
      *
      * @return \eZ\Publish\API\Repository\Values\Content\Content the content draft with the updated fields
      */
-    public function updateContent(VersionInfo $versionInfo, ContentUpdateStruct $contentUpdateStruct);
+    public function updateContent(VersionInfo $versionInfo, ContentUpdateStruct $contentUpdateStruct): Content;
 
     /**
      * Publishes a content version.
@@ -333,7 +333,7 @@ public function updateContent(VersionInfo $versionInfo, ContentUpdateStruct $con
      *
      * @return \eZ\Publish\API\Repository\Values\Content\Content
      */
-    public function publishVersion(VersionInfo $versionInfo, array $translations = Language::ALL);
+    public function publishVersion(VersionInfo $versionInfo, array $translations = Language::ALL): Content;
 
     /**
      * Removes the given version.
@@ -344,7 +344,7 @@ public function publishVersion(VersionInfo $versionInfo, array $translations = L
      *
      * @param \eZ\Publish\API\Repository\Values\Content\VersionInfo $versionInfo
      */
-    public function deleteVersion(VersionInfo $versionInfo);
+    public function deleteVersion(VersionInfo $versionInfo): void;
 
     /**
      * Loads all versions for the given content.
@@ -357,7 +357,7 @@ public function deleteVersion(VersionInfo $versionInfo);
      *
      * @return \eZ\Publish\API\Repository\Values\Content\VersionInfo[] an array of {@link \eZ\Publish\API\Repository\Values\Content\VersionInfo} sorted by creation date
      */
-    public function loadVersions(ContentInfo $contentInfo, ?int $status = null);
+    public function loadVersions(ContentInfo $contentInfo, ?int $status = null): iterable;
 
     /**
      * Copies the content to a new location. If no version is given,
@@ -371,7 +371,7 @@ public function loadVersions(ContentInfo $contentInfo, ?int $status = null);
      *
      * @return \eZ\Publish\API\Repository\Values\Content\Content
      */
-    public function copyContent(ContentInfo $contentInfo, LocationCreateStruct $destinationLocationCreateStruct, VersionInfo $versionInfo = null);
+    public function copyContent(ContentInfo $contentInfo, LocationCreateStruct $destinationLocationCreateStruct, ?VersionInfo $versionInfo = null): Content;
 
     /**
      * Loads all outgoing relations for the given version.
@@ -382,7 +382,7 @@ public function copyContent(ContentInfo $contentInfo, LocationCreateStruct $dest
      *
      * @return \eZ\Publish\API\Repository\Values\Content\Relation[]
      */
-    public function loadRelations(VersionInfo $versionInfo);
+    public function loadRelations(VersionInfo $versionInfo): iterable;
 
     /**
      * Counts all incoming relations for the given content object.
@@ -404,7 +404,7 @@ public function countReverseRelations(ContentInfo $contentInfo): int;
      *
      * @return \eZ\Publish\API\Repository\Values\Content\Relation[]
      */
-    public function loadReverseRelations(ContentInfo $contentInfo);
+    public function loadReverseRelations(ContentInfo $contentInfo): iterable;
 
     /**
      * Loads all incoming relations for a content object.
@@ -435,7 +435,7 @@ public function loadReverseRelationList(ContentInfo $contentInfo, int $offset =
      *
      * @return \eZ\Publish\API\Repository\Values\Content\Relation the newly created relation
      */
-    public function addRelation(VersionInfo $sourceVersion, ContentInfo $destinationContent);
+    public function addRelation(VersionInfo $sourceVersion, ContentInfo $destinationContent): Relation;
 
     /**
      * Removes a relation of type COMMON from a draft.
@@ -447,7 +447,7 @@ public function addRelation(VersionInfo $sourceVersion, ContentInfo $destination
      * @param \eZ\Publish\API\Repository\Values\Content\VersionInfo $sourceVersion
      * @param \eZ\Publish\API\Repository\Values\Content\ContentInfo $destinationContent
      */
-    public function deleteRelation(VersionInfo $sourceVersion, ContentInfo $destinationContent);
+    public function deleteRelation(VersionInfo $sourceVersion, ContentInfo $destinationContent): void;
 
     /**
      * Remove Content Object translation from all Versions (including archived ones) of a Content Object.
@@ -469,7 +469,7 @@ public function deleteRelation(VersionInfo $sourceVersion, ContentInfo $destinat
      *
      * @since 6.11
      */
-    public function removeTranslation(ContentInfo $contentInfo, $languageCode);
+    public function removeTranslation(ContentInfo $contentInfo, string $languageCode): void;
 
     /**
      * Delete Content item Translation from all Versions (including archived ones) of a Content Object.
@@ -488,7 +488,7 @@ public function removeTranslation(ContentInfo $contentInfo, $languageCode);
      *
      * @since 6.13
      */
-    public function deleteTranslation(ContentInfo $contentInfo, $languageCode);
+    public function deleteTranslation(ContentInfo $contentInfo, string $languageCode): void;
 
     /**
      * Delete specified Translation from a Content Draft.
@@ -511,7 +511,7 @@ public function deleteTranslation(ContentInfo $contentInfo, $languageCode);
      *
      * @since 6.12
      */
-    public function deleteTranslationFromDraft(VersionInfo $versionInfo, $languageCode);
+    public function deleteTranslationFromDraft(VersionInfo $versionInfo, string $languageCode): Content;
 
     /**
      * Hides Content by making all the Locations appear hidden.
@@ -545,19 +545,19 @@ public function revealContent(ContentInfo $contentInfo): void;
      *
      * @return \eZ\Publish\API\Repository\Values\Content\ContentCreateStruct
      */
-    public function newContentCreateStruct(ContentType $contentType, $mainLanguageCode);
+    public function newContentCreateStruct(ContentType $contentType, string $mainLanguageCode): ContentCreateStruct;
 
     /**
      * Instantiates a new content meta data update struct.
      *
      * @return \eZ\Publish\API\Repository\Values\Content\ContentMetadataUpdateStruct
      */
-    public function newContentMetadataUpdateStruct();
+    public function newContentMetadataUpdateStruct(): ContentMetadataUpdateStruct;
 
     /**
      * Instantiates a new content update struct.
      *
      * @return \eZ\Publish\API\Repository\Values\Content\ContentUpdateStruct
      */
-    public function newContentUpdateStruct();
+    public function newContentUpdateStruct(): ContentUpdateStruct;
 }
diff --git a/eZ/Publish/Core/Event/ContentService.php b/eZ/Publish/Core/Event/ContentService.php
index fcc560652a1..6a0188587b9 100644
--- a/eZ/Publish/Core/Event/ContentService.php
+++ b/eZ/Publish/Core/Event/ContentService.php
@@ -116,7 +116,7 @@ public function updateContentMetadata(
         return $content;
     }
 
-    public function deleteContent(ContentInfo $contentInfo): array
+    public function deleteContent(ContentInfo $contentInfo): iterable
     {
         $eventData = [$contentInfo];
 
@@ -140,8 +140,8 @@ public function deleteContent(ContentInfo $contentInfo): array
 
     public function createContentDraft(
         ContentInfo $contentInfo,
-        VersionInfo $versionInfo = null,
-        User $creator = null,
+        ?VersionInfo $versionInfo = null,
+        ?User $creator = null,
         ?Language $language = null
     ): Content {
         $eventData = [
@@ -242,7 +242,7 @@ public function deleteVersion(VersionInfo $versionInfo): void
     public function copyContent(
         ContentInfo $contentInfo,
         LocationCreateStruct $destinationLocationCreateStruct,
-        VersionInfo $versionInfo = null
+        ?VersionInfo $versionInfo = null
     ): Content {
         $eventData = [
             $contentInfo,
@@ -320,7 +320,7 @@ public function deleteRelation(
 
     public function deleteTranslation(
         ContentInfo $contentInfo,
-        $languageCode
+        string $languageCode
     ): void {
         $eventData = [
             $contentInfo,
diff --git a/eZ/Publish/Core/Persistence/Legacy/Content/Gateway/DoctrineDatabase.php b/eZ/Publish/Core/Persistence/Legacy/Content/Gateway/DoctrineDatabase.php
index ddcb2283f46..4584a027233 100644
--- a/eZ/Publish/Core/Persistence/Legacy/Content/Gateway/DoctrineDatabase.php
+++ b/eZ/Publish/Core/Persistence/Legacy/Content/Gateway/DoctrineDatabase.php
@@ -186,7 +186,7 @@ public function insertContentObject(CreateStruct $struct, $currentVersionNo = 1)
 
         $q->prepare()->execute();
 
-        return $this->dbHandler->lastInsertId(
+        return (int)$this->dbHandler->lastInsertId(
             $this->dbHandler->getSequenceName('ezcontentobject', 'id')
         );
     }
@@ -275,7 +275,7 @@ public function insertVersion(VersionInfo $versionInfo, array $fields)
 
         $q->prepare()->execute();
 
-        return $this->dbHandler->lastInsertId(
+        return (int)$this->dbHandler->lastInsertId(
             $this->dbHandler->getSequenceName('ezcontentobject_version', 'id')
         );
     }
@@ -689,7 +689,7 @@ public function insertNewField(Content $content, Field $field, StorageFieldValue
 
         $q->prepare()->execute();
 
-        return $this->dbHandler->lastInsertId(
+        return (int)$this->dbHandler->lastInsertId(
             $this->dbHandler->getSequenceName('ezcontentobject_attribute', 'id')
         );
     }
@@ -2113,7 +2113,7 @@ public function insertRelation(RelationCreateStruct $createStruct)
 
         $q->prepare()->execute();
 
-        return $this->dbHandler->lastInsertId(
+        return (int)$this->dbHandler->lastInsertId(
             $this->dbHandler->getSequenceName('ezcontentobject_link', 'id')
         );
     }
diff --git a/eZ/Publish/Core/Repository/ContentService.php b/eZ/Publish/Core/Repository/ContentService.php
index b9c72063df2..bd2e3f84df3 100644
--- a/eZ/Publish/Core/Repository/ContentService.php
+++ b/eZ/Publish/Core/Repository/ContentService.php
@@ -1,11 +1,11 @@
 <?php
 
 /**
- * File containing the eZ\Publish\Core\Repository\ContentService class.
- *
  * @copyright Copyright (C) eZ Systems AS. All rights reserved.
  * @license For full copyright and license information view LICENSE file distributed with this source code.
  */
+declare(strict_types=1);
+
 namespace eZ\Publish\Core\Repository;
 
 use eZ\Publish\API\Repository\ContentService as ContentServiceInterface;
@@ -50,12 +50,11 @@
 use eZ\Publish\SPI\Persistence\Content\UpdateStruct as SPIContentUpdateStruct;
 use eZ\Publish\SPI\Persistence\Content\Field as SPIField;
 use eZ\Publish\SPI\Persistence\Content\Relation\CreateStruct as SPIRelationCreateStruct;
+use eZ\Publish\SPI\Persistence\Content\ContentInfo as SPIContentInfo;
 use Exception;
 
 /**
  * This class provides service methods for managing content.
- *
- * @example Examples/content.php
  */
 class ContentService implements ContentServiceInterface
 {
@@ -119,9 +118,9 @@ public function __construct(
      *
      * @return \eZ\Publish\API\Repository\Values\Content\ContentInfo
      */
-    public function loadContentInfo($contentId)
+    public function loadContentInfo(int $contentId): ContentInfo
     {
-        $contentInfo = $this->internalLoadContentInfo($contentId);
+        $contentInfo = $this->internalLoadContentInfoById($contentId);
         if (!$this->permissionResolver->canUser('content', 'read', $contentInfo)) {
             throw new UnauthorizedException('content', 'read', ['contentId' => $contentId]);
         }
@@ -149,29 +148,40 @@ public function loadContentInfoList(array $contentIds): iterable
     /**
      * Loads a content info object.
      *
-     * To load fields use loadContent
-     *
      * @throws \eZ\Publish\API\Repository\Exceptions\NotFoundException - if the content with the given id does not exist
      *
-     * @param mixed $id
-     * @param bool $isRemoteId
+     * @param int $id
      *
      * @return \eZ\Publish\API\Repository\Values\Content\ContentInfo
      */
-    public function internalLoadContentInfo($id, $isRemoteId = false)
+    public function internalLoadContentInfoById(int $id): ContentInfo
     {
         try {
-            $method = $isRemoteId ? 'loadContentInfoByRemoteId' : 'loadContentInfo';
-
             return $this->domainMapper->buildContentInfoDomainObject(
-                $this->persistenceHandler->contentHandler()->$method($id)
+                $this->persistenceHandler->contentHandler()->loadContentInfo($id)
             );
         } catch (APINotFoundException $e) {
-            throw new NotFoundException(
-                'Content',
-                $id,
-                $e
+            throw new NotFoundException('Content', $id, $e);
+        }
+    }
+
+    /**
+     * Loads a content info object by remote id.
+     *
+     * @throws \eZ\Publish\API\Repository\Exceptions\NotFoundException - if the content with the given id does not exist
+     *
+     * @param string $remoteId
+     *
+     * @return \eZ\Publish\API\Repository\Values\Content\ContentInfo
+     */
+    public function internalLoadContentInfoByRemoteId(string $remoteId): ContentInfo
+    {
+        try {
+            return $this->domainMapper->buildContentInfoDomainObject(
+                $this->persistenceHandler->contentHandler()->loadContentInfoByRemoteId($remoteId)
             );
+        } catch (APINotFoundException $e) {
+            throw new NotFoundException('Content', $remoteId, $e);
         }
     }
 
@@ -187,9 +197,9 @@ public function internalLoadContentInfo($id, $isRemoteId = false)
      *
      * @return \eZ\Publish\API\Repository\Values\Content\ContentInfo
      */
-    public function loadContentInfoByRemoteId($remoteId)
+    public function loadContentInfoByRemoteId(string $remoteId): ContentInfo
     {
-        $contentInfo = $this->internalLoadContentInfo($remoteId, true);
+        $contentInfo = $this->internalLoadContentInfoByRemoteId($remoteId);
 
         if (!$this->permissionResolver->canUser('content', 'read', $contentInfo)) {
             throw new UnauthorizedException('content', 'read', ['remoteId' => $remoteId]);
@@ -207,11 +217,11 @@ public function loadContentInfoByRemoteId($remoteId)
      * @throws \eZ\Publish\API\Repository\Exceptions\UnauthorizedException if the user is not allowed to load this version
      *
      * @param \eZ\Publish\API\Repository\Values\Content\ContentInfo $contentInfo
-     * @param int $versionNo the version number. If not given the current version is returned.
+     * @param int|null $versionNo the version number. If not given the current version is returned.
      *
      * @return \eZ\Publish\API\Repository\Values\Content\VersionInfo
      */
-    public function loadVersionInfo(ContentInfo $contentInfo, $versionNo = null)
+    public function loadVersionInfo(ContentInfo $contentInfo, ?int $versionNo = null): APIVersionInfo
     {
         return $this->loadVersionInfoById($contentInfo->id, $versionNo);
     }
@@ -224,12 +234,12 @@ public function loadVersionInfo(ContentInfo $contentInfo, $versionNo = null)
      * @throws \eZ\Publish\API\Repository\Exceptions\NotFoundException - if the version with the given number does not exist
      * @throws \eZ\Publish\API\Repository\Exceptions\UnauthorizedException if the user is not allowed to load this version
      *
-     * @param mixed $contentId
-     * @param int $versionNo the version number. If not given the current version is returned.
+     * @param int $contentId
+     * @param int|null $versionNo the version number. If not given the current version is returned.
      *
      * @return \eZ\Publish\API\Repository\Values\Content\VersionInfo
      */
-    public function loadVersionInfoById($contentId, $versionNo = null)
+    public function loadVersionInfoById(int $contentId, ?int $versionNo = null): APIVersionInfo
     {
         try {
             $spiVersionInfo = $this->persistenceHandler->contentHandler()->loadVersionInfo(
@@ -265,7 +275,7 @@ public function loadVersionInfoById($contentId, $versionNo = null)
     /**
      * {@inheritdoc}
      */
-    public function loadContentByContentInfo(ContentInfo $contentInfo, array $languages = null, $versionNo = null, $useAlwaysAvailable = true)
+    public function loadContentByContentInfo(ContentInfo $contentInfo, array $languages = null, ?int $versionNo = null, bool $useAlwaysAvailable = true): APIContent
     {
         // Change $useAlwaysAvailable to false to avoid contentInfo lookup if we know alwaysAvailable is disabled
         if ($useAlwaysAvailable && !$contentInfo->alwaysAvailable) {
@@ -283,7 +293,7 @@ public function loadContentByContentInfo(ContentInfo $contentInfo, array $langua
     /**
      * {@inheritdoc}
      */
-    public function loadContentByVersionInfo(APIVersionInfo $versionInfo, array $languages = null, $useAlwaysAvailable = true)
+    public function loadContentByVersionInfo(APIVersionInfo $versionInfo, array $languages = null, bool $useAlwaysAvailable = true): APIContent
     {
         // Change $useAlwaysAvailable to false to avoid contentInfo lookup if we know alwaysAvailable is disabled
         if ($useAlwaysAvailable && !$versionInfo->getContentInfo()->alwaysAvailable) {
@@ -301,9 +311,9 @@ public function loadContentByVersionInfo(APIVersionInfo $versionInfo, array $lan
     /**
      * {@inheritdoc}
      */
-    public function loadContent($contentId, array $languages = null, $versionNo = null, $useAlwaysAvailable = true)
+    public function loadContent(int $contentId, array $languages = null, ?int $versionNo = null, bool $useAlwaysAvailable = true): APIContent
     {
-        $content = $this->internalLoadContent($contentId, $languages, $versionNo, false, $useAlwaysAvailable);
+        $content = $this->internalLoadContentById($contentId, $languages, $versionNo, $useAlwaysAvailable);
 
         if (!$this->permissionResolver->canUser('content', 'read', $content)) {
             throw new UnauthorizedException('content', 'read', ['contentId' => $contentId]);
@@ -318,65 +328,78 @@ public function loadContent($contentId, array $languages = null, $versionNo = nu
         return $content;
     }
 
-    /**
-     * Loads content in a version of the given content object.
-     *
-     * If no version number is given, the method returns the current version
-     *
-     * @internal
-     * @throws \eZ\Publish\API\Repository\Exceptions\NotFoundException if the content or version with the given id and languages does not exist
-     *
-     * @param mixed $id
-     * @param array|null $languages A language priority, filters returned fields and is used as prioritized language code on
-     *                         returned value object. If not given all languages are returned.
-     * @param int|null $versionNo the version number. If not given the current version is returned
-     * @param bool $isRemoteId
-     * @param bool $useAlwaysAvailable Add Main language to \$languages if true (default) and if alwaysAvailable is true
-     *
-     * @return \eZ\Publish\API\Repository\Values\Content\Content
-     */
-    public function internalLoadContent($id, array $languages = null, $versionNo = null, $isRemoteId = false, $useAlwaysAvailable = true)
-    {
+    public function internalLoadContentById(
+        int $id,
+        ?array $languages = null,
+        int $versionNo = null,
+        bool $useAlwaysAvailable = true
+    ): APIContent {
         try {
-            // Get Content ID if lookup by remote ID
-            if ($isRemoteId) {
-                $spiContentInfo = $this->persistenceHandler->contentHandler()->loadContentInfoByRemoteId($id);
-                $id = $spiContentInfo->id;
-                // Set $isRemoteId to false as the next loads will be for content id now that we have it (for exception use now)
-                $isRemoteId = false;
-            }
+            $spiContentInfo = $this->persistenceHandler->contentHandler()->loadContentInfo($id);
 
-            $loadLanguages = $languages;
-            $alwaysAvailableLanguageCode = null;
-            // Set main language on $languages filter if not empty (all) and $useAlwaysAvailable being true
-            // @todo Move use always available logic to SPI load methods, like done in location handler in 7.x
-            if (!empty($loadLanguages) && $useAlwaysAvailable) {
-                if (!isset($spiContentInfo)) {
-                    $spiContentInfo = $this->persistenceHandler->contentHandler()->loadContentInfo($id);
-                }
+            return $this->internalLoadContentBySPIContentInfo(
+                $spiContentInfo,
+                $languages,
+                $versionNo,
+                $useAlwaysAvailable
+            );
+        } catch (APINotFoundException $e) {
+            throw new NotFoundException(
+                'Content',
+                [
+                    'id' => $id,
+                    'languages' => $languages,
+                    'versionNo' => $versionNo,
+                ],
+                $e
+            );
+        }
+    }
 
-                if ($spiContentInfo->alwaysAvailable) {
-                    $loadLanguages[] = $alwaysAvailableLanguageCode = $spiContentInfo->mainLanguageCode;
-                    $loadLanguages = array_unique($loadLanguages);
-                }
-            }
+    public function internalLoadContentByRemoteId(
+        string $remoteId,
+        array $languages = null,
+        int $versionNo = null,
+        bool $useAlwaysAvailable = true
+    ): APIContent {
+        try {
+            $spiContentInfo = $this->persistenceHandler->contentHandler()->loadContentInfoByRemoteId($remoteId);
 
-            $spiContent = $this->persistenceHandler->contentHandler()->load(
-                $id,
+            return $this->internalLoadContentBySPIContentInfo(
+                $spiContentInfo,
+                $languages,
                 $versionNo,
-                $loadLanguages
+                $useAlwaysAvailable
             );
         } catch (APINotFoundException $e) {
             throw new NotFoundException(
                 'Content',
                 [
-                    $isRemoteId ? 'remoteId' : 'id' => $id,
+                    'remoteId' => $remoteId,
                     'languages' => $languages,
                     'versionNo' => $versionNo,
                 ],
                 $e
             );
         }
+    }
+
+    private function internalLoadContentBySPIContentInfo(SPIContentInfo $spiContentInfo, array $languages = null, int $versionNo = null, bool $useAlwaysAvailable = true): APIContent
+    {
+        $loadLanguages = $languages;
+        $alwaysAvailableLanguageCode = null;
+        // Set main language on $languages filter if not empty (all) and $useAlwaysAvailable being true
+        // @todo Move use always available logic to SPI load methods, like done in location handler in 7.x
+        if (!empty($loadLanguages) && $useAlwaysAvailable && $spiContentInfo->alwaysAvailable) {
+            $loadLanguages[] = $alwaysAvailableLanguageCode = $spiContentInfo->mainLanguageCode;
+            $loadLanguages = array_unique($loadLanguages);
+        }
+
+        $spiContent = $this->persistenceHandler->contentHandler()->load(
+            $spiContentInfo->id,
+            $versionNo,
+            $loadLanguages
+        );
 
         if ($languages === null) {
             $languages = [];
@@ -408,9 +431,9 @@ public function internalLoadContent($id, array $languages = null, $versionNo = n
      *
      * @return \eZ\Publish\API\Repository\Values\Content\Content
      */
-    public function loadContentByRemoteId($remoteId, array $languages = null, $versionNo = null, $useAlwaysAvailable = true)
+    public function loadContentByRemoteId(string $remoteId, array $languages = null, ?int $versionNo = null, bool $useAlwaysAvailable = true): APIContent
     {
-        $content = $this->internalLoadContent($remoteId, $languages, $versionNo, true, $useAlwaysAvailable);
+        $content = $this->internalLoadContentByRemoteId($remoteId, $languages, $versionNo, $useAlwaysAvailable);
 
         if (!$this->permissionResolver->canUser('content', 'read', $content)) {
             throw new UnauthorizedException('content', 'read', ['remoteId' => $remoteId]);
@@ -444,8 +467,8 @@ public function loadContentByRemoteId($remoteId, array $languages = null, $versi
     public function loadContentListByContentInfo(
         array $contentInfoList,
         array $languages = [],
-        $useAlwaysAvailable = true
-    ) {
+        bool $useAlwaysAvailable = true
+    ): iterable {
         $loadAllLanguages = $languages === Language::ALL;
         $contentIds = [];
         $contentTypeIds = [];
@@ -508,7 +531,7 @@ public function loadContentListByContentInfo(
      *
      * @return \eZ\Publish\API\Repository\Values\Content\Content - the newly created content draft
      */
-    public function createContent(APIContentCreateStruct $contentCreateStruct, array $locationCreateStructs = [])
+    public function createContent(APIContentCreateStruct $contentCreateStruct, array $locationCreateStructs = []): APIContent
     {
         if ($contentCreateStruct->mainLanguageCode === null) {
             throw new InvalidArgumentException('$contentCreateStruct', "'mainLanguageCode' property must be set");
@@ -716,7 +739,7 @@ public function createContent(APIContentCreateStruct $contentCreateStruct, array
      *
      * @return \eZ\Publish\SPI\Persistence\Content\ObjectState[]
      */
-    protected function getDefaultObjectStates()
+    protected function getDefaultObjectStates(): array
     {
         $defaultObjectStatesMap = [];
         $objectStateHandler = $this->persistenceHandler->objectStateHandler();
@@ -741,7 +764,7 @@ protected function getDefaultObjectStates()
      *
      * @return string[]
      */
-    protected function getLanguageCodesForCreate(APIContentCreateStruct $contentCreateStruct)
+    protected function getLanguageCodesForCreate(APIContentCreateStruct $contentCreateStruct): array
     {
         $languageCodes = [];
 
@@ -777,7 +800,7 @@ protected function getLanguageCodesForCreate(APIContentCreateStruct $contentCrea
      *
      * @return array
      */
-    protected function mapFieldsForCreate(APIContentCreateStruct $contentCreateStruct)
+    protected function mapFieldsForCreate(APIContentCreateStruct $contentCreateStruct): array
     {
         $fields = [];
 
@@ -819,7 +842,7 @@ protected function mapFieldsForCreate(APIContentCreateStruct $contentCreateStruc
      *
      * @return Field
      */
-    private function cloneField(Field $field, array $overrides = [])
+    private function cloneField(Field $field, array $overrides = []): Field
     {
         $fieldData = array_merge(
             [
@@ -842,7 +865,7 @@ private function cloneField(Field $field, array $overrides = [])
      *
      * @return \eZ\Publish\SPI\Persistence\Content\Location\CreateStruct[]
      */
-    protected function buildSPILocationCreateStructs(array $locationCreateStructs)
+    protected function buildSPILocationCreateStructs(array $locationCreateStructs): array
     {
         $spiLocationCreateStructs = [];
         $parentLocationIdSet = [];
@@ -898,7 +921,7 @@ protected function buildSPILocationCreateStructs(array $locationCreateStructs)
      *
      * @return \eZ\Publish\API\Repository\Values\Content\Content the content with the updated attributes
      */
-    public function updateContentMetadata(ContentInfo $contentInfo, ContentMetadataUpdateStruct $contentMetadataUpdateStruct)
+    public function updateContentMetadata(ContentInfo $contentInfo, ContentMetadataUpdateStruct $contentMetadataUpdateStruct): APIContent
     {
         $propertyCount = 0;
         foreach ($contentMetadataUpdateStruct as $propertyName => $propertyValue) {
@@ -993,7 +1016,7 @@ public function updateContentMetadata(ContentInfo $contentInfo, ContentMetadataU
      * @param bool $updatePathIdentificationString this parameter is legacy storage specific for updating
      *                      ezcontentobject_tree.path_identification_string, it is ignored by other storage engines
      */
-    protected function publishUrlAliasesForContent(APIContent $content, $updatePathIdentificationString = true)
+    protected function publishUrlAliasesForContent(APIContent $content, bool $updatePathIdentificationString = true): void
     {
         $urlAliasNames = $this->nameSchemaService->resolveUrlAliasSchema($content);
         $locations = $this->repository->getLocationService()->loadLocations(
@@ -1029,9 +1052,9 @@ protected function publishUrlAliasesForContent(APIContent $content, $updatePathI
      *
      * @return mixed[] Affected Location Id's
      */
-    public function deleteContent(ContentInfo $contentInfo)
+    public function deleteContent(ContentInfo $contentInfo): iterable
     {
-        $contentInfo = $this->internalLoadContentInfo($contentInfo->id);
+        $contentInfo = $this->internalLoadContentInfoById($contentInfo->id);
 
         if (!$this->permissionResolver->canUser('content', 'remove', $contentInfo)) {
             throw new UnauthorizedException('content', 'remove', ['contentId' => $contentInfo->id]);
@@ -1063,8 +1086,8 @@ public function deleteContent(ContentInfo $contentInfo)
      * If no version is given, the current published version is used.
      *
      * @param \eZ\Publish\API\Repository\Values\Content\ContentInfo $contentInfo
-     * @param \eZ\Publish\API\Repository\Values\Content\VersionInfo $versionInfo
-     * @param \eZ\Publish\API\Repository\Values\User\User $creator if set given user is used to create the draft - otherwise the current-user is used
+     * @param \eZ\Publish\API\Repository\Values\Content\VersionInfo|null $versionInfo
+     * @param \eZ\Publish\API\Repository\Values\User\User|null $creator if set given user is used to create the draft - otherwise the current-user is used
      * @param \eZ\Publish\API\Repository\Values\Content\Language|null if not set the draft is created with the initialLanguage code of the source version or if not present with the main language.
      *
      * @return \eZ\Publish\API\Repository\Values\Content\Content - the newly created content draft
@@ -1075,10 +1098,10 @@ public function deleteContent(ContentInfo $contentInfo)
      */
     public function createContentDraft(
         ContentInfo $contentInfo,
-        APIVersionInfo $versionInfo = null,
-        User $creator = null,
+        ?APIVersionInfo $versionInfo = null,
+        ?User $creator = null,
         ?Language $language = null
-    ) {
+    ): APIContent {
         $contentInfo = $this->loadContentInfo($contentInfo->id);
 
         if ($versionInfo !== null) {
@@ -1186,7 +1209,7 @@ public function countContentDrafts(?User $user = null): int
      * @throws \eZ\Publish\API\Repository\Exceptions\UnauthorizedException
      * @throws \eZ\Publish\API\Repository\Exceptions\InvalidArgumentException
      */
-    public function loadContentDrafts(User $user = null)
+    public function loadContentDrafts(?User $user = null): iterable
     {
         // throw early if user has absolutely no access to versionread
         if ($this->permissionResolver->hasAccess('content', 'versionread') === false) {
@@ -1262,7 +1285,7 @@ public function loadContentDraftList(?User $user = null, int $offset = 0, int $l
      * @throws \eZ\Publish\API\Repository\Exceptions\InvalidArgumentException if a property on the struct is invalid.
      * @throws \eZ\Publish\API\Repository\Exceptions\NotFoundException
      */
-    public function updateContent(APIVersionInfo $versionInfo, APIContentUpdateStruct $contentUpdateStruct)
+    public function updateContent(APIVersionInfo $versionInfo, APIContentUpdateStruct $contentUpdateStruct): APIContent
     {
         $contentUpdateStruct = clone $contentUpdateStruct;
 
@@ -1457,7 +1480,7 @@ public function updateContent(APIVersionInfo $versionInfo, APIContentUpdateStruc
      *
      * @return array
      */
-    private function getUpdatedLanguageCodes(APIContentUpdateStruct $contentUpdateStruct)
+    private function getUpdatedLanguageCodes(APIContentUpdateStruct $contentUpdateStruct): array
     {
         $languageCodes = [
             $contentUpdateStruct->initialLanguageCode => true,
@@ -1484,7 +1507,7 @@ private function getUpdatedLanguageCodes(APIContentUpdateStruct $contentUpdateSt
      *
      * @return array
      */
-    protected function getLanguageCodesForUpdate(APIContentUpdateStruct $contentUpdateStruct, APIContent $content)
+    protected function getLanguageCodesForUpdate(APIContentUpdateStruct $contentUpdateStruct, APIContent $content): array
     {
         $languageCodes = array_fill_keys($content->versionInfo->languageCodes, true);
         $languageCodes[$contentUpdateStruct->initialLanguageCode] = true;
@@ -1513,8 +1536,8 @@ protected function getLanguageCodesForUpdate(APIContentUpdateStruct $contentUpda
     protected function mapFieldsForUpdate(
         APIContentUpdateStruct $contentUpdateStruct,
         ContentType $contentType,
-        $mainLanguageCode
-    ) {
+        string $mainLanguageCode
+    ): array {
         $fields = [];
 
         foreach ($contentUpdateStruct->fields as $field) {
@@ -1565,9 +1588,9 @@ protected function mapFieldsForUpdate(
      * @throws \eZ\Publish\API\Repository\Exceptions\NotFoundException
      * @throws \eZ\Publish\API\Repository\Exceptions\UnauthorizedException
      */
-    public function publishVersion(APIVersionInfo $versionInfo, array $translations = Language::ALL)
+    public function publishVersion(APIVersionInfo $versionInfo, array $translations = Language::ALL): APIContent
     {
-        $content = $this->internalLoadContent(
+        $content = $this->internalLoadContentById(
             $versionInfo->contentInfo->id,
             null,
             $versionInfo->versionNo
@@ -1575,7 +1598,7 @@ public function publishVersion(APIVersionInfo $versionInfo, array $translations
 
         $fromContent = null;
         if ($content->contentInfo->currentVersionNo !== $versionInfo->versionNo) {
-            $fromContent = $this->internalLoadContent(
+            $fromContent = $this->internalLoadContentById(
                 $content->contentInfo->id,
                 null,
                 $content->contentInfo->currentVersionNo
@@ -1624,7 +1647,7 @@ protected function copyTranslationsFromPublishedVersion(APIVersionInfo $versionI
     {
         $contendId = $versionInfo->contentInfo->id;
 
-        $currentContent = $this->internalLoadContent($contendId);
+        $currentContent = $this->internalLoadContentById($contendId);
         $currentVersionInfo = $currentContent->versionInfo;
 
         // Copying occurs only if:
@@ -1659,7 +1682,7 @@ protected function copyTranslationsFromPublishedVersion(APIVersionInfo $versionI
         $updateStruct = $this->newContentUpdateStruct();
         $updateStruct->initialLanguageCode = $versionInfo->initialLanguageCode;
 
-        $contentToPublish = $this->internalLoadContent($contendId, null, $versionInfo->versionNo);
+        $contentToPublish = $this->internalLoadContentById($contendId, null, $versionInfo->versionNo);
         $fallbackUpdateStruct = $this->newContentUpdateStruct();
 
         foreach ($currentContent->getFields() as $field) {
@@ -1784,7 +1807,7 @@ protected function internalPublishVersion(APIVersionInfo $versionInfo, $publicat
     /**
      * @return int
      */
-    protected function getUnixTimestamp()
+    protected function getUnixTimestamp(): int
     {
         return time();
     }
@@ -1798,7 +1821,7 @@ protected function getUnixTimestamp()
      *
      * @param \eZ\Publish\API\Repository\Values\Content\VersionInfo $versionInfo
      */
-    public function deleteVersion(APIVersionInfo $versionInfo)
+    public function deleteVersion(APIVersionInfo $versionInfo): void
     {
         if ($versionInfo->isPublished()) {
             throw new BadStateException(
@@ -1852,7 +1875,7 @@ public function deleteVersion(APIVersionInfo $versionInfo)
      *
      * @return \eZ\Publish\API\Repository\Values\Content\VersionInfo[] Sorted by creation date
      */
-    public function loadVersions(ContentInfo $contentInfo, ?int $status = null)
+    public function loadVersions(ContentInfo $contentInfo, ?int $status = null): iterable
     {
         if (!$this->permissionResolver->canUser('content', 'versionread', $contentInfo)) {
             throw new UnauthorizedException('content', 'versionread', ['contentId' => $contentInfo->id]);
@@ -1894,7 +1917,7 @@ public function loadVersions(ContentInfo $contentInfo, ?int $status = null)
      *
      * @return \eZ\Publish\API\Repository\Values\Content\Content
      */
-    public function copyContent(ContentInfo $contentInfo, LocationCreateStruct $destinationLocationCreateStruct, APIVersionInfo $versionInfo = null)
+    public function copyContent(ContentInfo $contentInfo, LocationCreateStruct $destinationLocationCreateStruct, ?APIVersionInfo $versionInfo = null): APIContent
     {
         $destinationLocation = $this->repository->getLocationService()->loadLocation(
             $destinationLocationCreateStruct->parentLocationId
@@ -1947,7 +1970,7 @@ public function copyContent(ContentInfo $contentInfo, LocationCreateStruct $dest
             throw $e;
         }
 
-        return $this->internalLoadContent($content->id);
+        return $this->internalLoadContentById($content->id);
     }
 
     /**
@@ -1959,7 +1982,7 @@ public function copyContent(ContentInfo $contentInfo, LocationCreateStruct $dest
      *
      * @return \eZ\Publish\API\Repository\Values\Content\Relation[]
      */
-    public function loadRelations(APIVersionInfo $versionInfo)
+    public function loadRelations(APIVersionInfo $versionInfo): iterable
     {
         if ($versionInfo->isPublished()) {
             $function = 'read';
@@ -1980,7 +2003,7 @@ public function loadRelations(APIVersionInfo $versionInfo)
         /** @var $relations \eZ\Publish\API\Repository\Values\Content\Relation[] */
         $relations = [];
         foreach ($spiRelations as $spiRelation) {
-            $destinationContentInfo = $this->internalLoadContentInfo($spiRelation->destinationContentId);
+            $destinationContentInfo = $this->internalLoadContentInfoById($spiRelation->destinationContentId);
             if (!$this->permissionResolver->canUser('content', 'read', $destinationContentInfo)) {
                 continue;
             }
@@ -2020,7 +2043,7 @@ public function countReverseRelations(ContentInfo $contentInfo): int
      *
      * @return \eZ\Publish\API\Repository\Values\Content\Relation[]
      */
-    public function loadReverseRelations(ContentInfo $contentInfo)
+    public function loadReverseRelations(ContentInfo $contentInfo): iterable
     {
         if (!$this->permissionResolver->canUser('content', 'reverserelatedlist', $contentInfo)) {
             throw new UnauthorizedException('content', 'reverserelatedlist', ['contentId' => $contentInfo->id]);
@@ -2032,7 +2055,7 @@ public function loadReverseRelations(ContentInfo $contentInfo)
 
         $returnArray = [];
         foreach ($spiRelations as $spiRelation) {
-            $sourceContentInfo = $this->internalLoadContentInfo($spiRelation->sourceContentId);
+            $sourceContentInfo = $this->internalLoadContentInfoById($spiRelation->sourceContentId);
             if (!$this->permissionResolver->canUser('content', 'read', $sourceContentInfo)) {
                 continue;
             }
@@ -2067,7 +2090,7 @@ public function loadReverseRelationList(ContentInfo $contentInfo, int $offset =
                 $limit
             );
             foreach ($spiRelationList as $spiRelation) {
-                $sourceContentInfo = $this->internalLoadContentInfo($spiRelation->sourceContentId);
+                $sourceContentInfo = $this->internalLoadContentInfoById($spiRelation->sourceContentId);
                 if ($this->repository->getPermissionResolver()->canUser('content', 'read', $sourceContentInfo)) {
                     $relation = $this->domainMapper->buildRelationDomainObject(
                         $spiRelation,
@@ -2102,7 +2125,7 @@ public function loadReverseRelationList(ContentInfo $contentInfo, int $offset =
      *
      * @return \eZ\Publish\API\Repository\Values\Content\Relation the newly created relation
      */
-    public function addRelation(APIVersionInfo $sourceVersion, ContentInfo $destinationContent)
+    public function addRelation(APIVersionInfo $sourceVersion, ContentInfo $destinationContent): APIRelation
     {
         $sourceVersion = $this->loadVersionInfoById(
             $sourceVersion->contentInfo->id,
@@ -2154,7 +2177,7 @@ public function addRelation(APIVersionInfo $sourceVersion, ContentInfo $destinat
      * @param \eZ\Publish\API\Repository\Values\Content\VersionInfo $sourceVersion
      * @param \eZ\Publish\API\Repository\Values\Content\ContentInfo $destinationContent
      */
-    public function deleteRelation(APIVersionInfo $sourceVersion, ContentInfo $destinationContent)
+    public function deleteRelation(APIVersionInfo $sourceVersion, ContentInfo $destinationContent): void
     {
         $sourceVersion = $this->loadVersionInfoById(
             $sourceVersion->contentInfo->id,
@@ -2208,7 +2231,7 @@ public function deleteRelation(APIVersionInfo $sourceVersion, ContentInfo $desti
     /**
      * {@inheritdoc}
      */
-    public function removeTranslation(ContentInfo $contentInfo, $languageCode)
+    public function removeTranslation(ContentInfo $contentInfo, string $languageCode): void
     {
         @trigger_error(
             __METHOD__ . ' is deprecated, use deleteTranslation instead',
@@ -2234,7 +2257,7 @@ public function removeTranslation(ContentInfo $contentInfo, $languageCode)
      *
      * @since 6.13
      */
-    public function deleteTranslation(ContentInfo $contentInfo, $languageCode)
+    public function deleteTranslation(ContentInfo $contentInfo, string $languageCode): void
     {
         if ($contentInfo->mainLanguageCode === $languageCode) {
             throw new BadStateException(
@@ -2330,7 +2353,7 @@ function (Location $location) {
      *
      * @since 6.12
      */
-    public function deleteTranslationFromDraft(APIVersionInfo $versionInfo, $languageCode)
+    public function deleteTranslationFromDraft(APIVersionInfo $versionInfo, string $languageCode): APIContent
     {
         if (!$versionInfo->isDraft()) {
             throw new BadStateException(
@@ -2477,7 +2500,7 @@ public function revealContent(ContentInfo $contentInfo): void
      *
      * @return \eZ\Publish\API\Repository\Values\Content\ContentCreateStruct
      */
-    public function newContentCreateStruct(ContentType $contentType, $mainLanguageCode)
+    public function newContentCreateStruct(ContentType $contentType, string $mainLanguageCode): APIContentCreateStruct
     {
         return new ContentCreateStruct(
             [
@@ -2493,7 +2516,7 @@ public function newContentCreateStruct(ContentType $contentType, $mainLanguageCo
      *
      * @return \eZ\Publish\API\Repository\Values\Content\ContentMetadataUpdateStruct
      */
-    public function newContentMetadataUpdateStruct()
+    public function newContentMetadataUpdateStruct(): ContentMetadataUpdateStruct
     {
         return new ContentMetadataUpdateStruct();
     }
@@ -2503,7 +2526,7 @@ public function newContentMetadataUpdateStruct()
      *
      * @return \eZ\Publish\API\Repository\Values\Content\ContentUpdateStruct
      */
-    public function newContentUpdateStruct()
+    public function newContentUpdateStruct(): APIContentUpdateStruct
     {
         return new ContentUpdateStruct();
     }
diff --git a/eZ/Publish/Core/Repository/SearchService.php b/eZ/Publish/Core/Repository/SearchService.php
index 4ed0bda773f..93a4b57e70d 100644
--- a/eZ/Publish/Core/Repository/SearchService.php
+++ b/eZ/Publish/Core/Repository/SearchService.php
@@ -242,11 +242,10 @@ public function findSingle(Criterion $filter, array $languageFilter = [], bool $
 
         $contentInfo = $this->searchHandler->findSingle($filter, $languageFilter);
 
-        return $this->repository->getContentService()->internalLoadContent(
+        return $this->repository->getContentService()->internalLoadContentById(
             $contentInfo->id,
             (!empty($languageFilter['languages']) ? $languageFilter['languages'] : null),
             null,
-            false,
             (isset($languageFilter['useAlwaysAvailable']) ? $languageFilter['useAlwaysAvailable'] : true)
         );
     }
diff --git a/eZ/Publish/Core/Repository/SiteAccessAware/ContentService.php b/eZ/Publish/Core/Repository/SiteAccessAware/ContentService.php
index 47fdc56f5fb..e0d27ea962b 100644
--- a/eZ/Publish/Core/Repository/SiteAccessAware/ContentService.php
+++ b/eZ/Publish/Core/Repository/SiteAccessAware/ContentService.php
@@ -1,11 +1,11 @@
 <?php
 
 /**
- * ContentService class.
- *
  * @copyright Copyright (C) eZ Systems AS. All rights reserved.
  * @license For full copyright and license information view LICENSE file distributed with this source code.
  */
+declare(strict_types=1);
+
 namespace eZ\Publish\Core\Repository\SiteAccessAware;
 
 use eZ\Publish\API\Repository\ContentService as ContentServiceInterface;
@@ -13,6 +13,8 @@
 use eZ\Publish\API\Repository\Values\Content\ContentCreateStruct;
 use eZ\Publish\API\Repository\Values\Content\ContentUpdateStruct;
 use eZ\Publish\API\Repository\Values\Content\ContentMetadataUpdateStruct;
+use eZ\Publish\API\Repository\Values\Content\Content;
+use eZ\Publish\API\Repository\Values\Content\Relation;
 use eZ\Publish\API\Repository\Values\Content\Language;
 use eZ\Publish\API\Repository\Values\Content\LocationCreateStruct;
 use eZ\Publish\API\Repository\Values\Content\RelationList;
@@ -47,7 +49,7 @@ public function __construct(
         $this->languageResolver = $languageResolver;
     }
 
-    public function loadContentInfo($contentId)
+    public function loadContentInfo(int $contentId): ContentInfo
     {
         return $this->service->loadContentInfo($contentId);
     }
@@ -60,22 +62,22 @@ public function loadContentInfoList(array $contentIds): iterable
         return $this->service->loadContentInfoList($contentIds);
     }
 
-    public function loadContentInfoByRemoteId($remoteId)
+    public function loadContentInfoByRemoteId(string $remoteId): ContentInfo
     {
         return $this->service->loadContentInfoByRemoteId($remoteId);
     }
 
-    public function loadVersionInfo(ContentInfo $contentInfo, $versionNo = null)
+    public function loadVersionInfo(ContentInfo $contentInfo, ?int $versionNo = null): VersionInfo
     {
         return $this->service->loadVersionInfo($contentInfo, $versionNo);
     }
 
-    public function loadVersionInfoById($contentId, $versionNo = null)
+    public function loadVersionInfoById(int $contentId, ?int $versionNo = null): VersionInfo
     {
         return $this->service->loadVersionInfoById($contentId, $versionNo);
     }
 
-    public function loadContentByContentInfo(ContentInfo $contentInfo, array $languages = null, $versionNo = null, $useAlwaysAvailable = null)
+    public function loadContentByContentInfo(ContentInfo $contentInfo, array $languages = null, ?int $versionNo = null, bool $useAlwaysAvailable = true): Content
     {
         return $this->service->loadContentByContentInfo(
             $contentInfo,
@@ -85,7 +87,7 @@ public function loadContentByContentInfo(ContentInfo $contentInfo, array $langua
         );
     }
 
-    public function loadContentByVersionInfo(VersionInfo $versionInfo, array $languages = null, $useAlwaysAvailable = null)
+    public function loadContentByVersionInfo(VersionInfo $versionInfo, array $languages = null, bool $useAlwaysAvailable = true): Content
     {
         return $this->service->loadContentByVersionInfo(
             $versionInfo,
@@ -94,7 +96,7 @@ public function loadContentByVersionInfo(VersionInfo $versionInfo, array $langua
         );
     }
 
-    public function loadContent($contentId, array $languages = null, $versionNo = null, $useAlwaysAvailable = null)
+    public function loadContent(int $contentId, array $languages = null, ?int $versionNo = null, bool $useAlwaysAvailable = true): Content
     {
         return $this->service->loadContent(
             $contentId,
@@ -104,7 +106,7 @@ public function loadContent($contentId, array $languages = null, $versionNo = nu
         );
     }
 
-    public function loadContentByRemoteId($remoteId, array $languages = null, $versionNo = null, $useAlwaysAvailable = null)
+    public function loadContentByRemoteId(string $remoteId, array $languages = null, ?int $versionNo = null, bool $useAlwaysAvailable = true): Content
     {
         return $this->service->loadContentByRemoteId(
             $remoteId,
@@ -114,27 +116,27 @@ public function loadContentByRemoteId($remoteId, array $languages = null, $versi
         );
     }
 
-    public function createContent(ContentCreateStruct $contentCreateStruct, array $locationCreateStructs = [])
+    public function createContent(ContentCreateStruct $contentCreateStruct, array $locationCreateStructs = []): Content
     {
         return $this->service->createContent($contentCreateStruct, $locationCreateStructs);
     }
 
-    public function updateContentMetadata(ContentInfo $contentInfo, ContentMetadataUpdateStruct $contentMetadataUpdateStruct)
+    public function updateContentMetadata(ContentInfo $contentInfo, ContentMetadataUpdateStruct $contentMetadataUpdateStruct): Content
     {
         return $this->service->updateContentMetadata($contentInfo, $contentMetadataUpdateStruct);
     }
 
-    public function deleteContent(ContentInfo $contentInfo)
+    public function deleteContent(ContentInfo $contentInfo): iterable
     {
         return $this->service->deleteContent($contentInfo);
     }
 
     public function createContentDraft(
         ContentInfo $contentInfo,
-        VersionInfo $versionInfo = null,
-        User $creator = null,
+        ?VersionInfo $versionInfo = null,
+        ?User $creator = null,
         ?Language $language = null
-    ) {
+    ): Content {
         return $this->service->createContentDraft($contentInfo, $versionInfo, $creator, $language);
     }
 
@@ -143,7 +145,7 @@ public function countContentDrafts(?User $user = null): int
         return $this->service->countContentDrafts($user);
     }
 
-    public function loadContentDrafts(User $user = null)
+    public function loadContentDrafts(?User $user = null): iterable
     {
         return $this->service->loadContentDrafts($user);
     }
@@ -153,32 +155,32 @@ public function loadContentDraftList(?User $user = null, int $offset = 0, int $l
         return $this->service->loadContentDraftList($user, $offset, $limit);
     }
 
-    public function updateContent(VersionInfo $versionInfo, ContentUpdateStruct $contentUpdateStruct)
+    public function updateContent(VersionInfo $versionInfo, ContentUpdateStruct $contentUpdateStruct): Content
     {
         return $this->service->updateContent($versionInfo, $contentUpdateStruct);
     }
 
-    public function publishVersion(VersionInfo $versionInfo, array $translations = Language::ALL)
+    public function publishVersion(VersionInfo $versionInfo, array $translations = Language::ALL): Content
     {
         return $this->service->publishVersion($versionInfo, $translations);
     }
 
-    public function deleteVersion(VersionInfo $versionInfo)
+    public function deleteVersion(VersionInfo $versionInfo): void
     {
-        return $this->service->deleteVersion($versionInfo);
+        $this->service->deleteVersion($versionInfo);
     }
 
-    public function loadVersions(ContentInfo $contentInfo, ?int $status = null)
+    public function loadVersions(ContentInfo $contentInfo, ?int $status = null): iterable
     {
         return $this->service->loadVersions($contentInfo, $status);
     }
 
-    public function copyContent(ContentInfo $contentInfo, LocationCreateStruct $destinationLocationCreateStruct, VersionInfo $versionInfo = null)
+    public function copyContent(ContentInfo $contentInfo, LocationCreateStruct $destinationLocationCreateStruct, ?VersionInfo $versionInfo = null): Content
     {
         return $this->service->copyContent($contentInfo, $destinationLocationCreateStruct, $versionInfo);
     }
 
-    public function loadRelations(VersionInfo $versionInfo)
+    public function loadRelations(VersionInfo $versionInfo): iterable
     {
         return $this->service->loadRelations($versionInfo);
     }
@@ -191,7 +193,7 @@ public function countReverseRelations(ContentInfo $contentInfo): int
         return $this->service->countReverseRelations($contentInfo);
     }
 
-    public function loadReverseRelations(ContentInfo $contentInfo)
+    public function loadReverseRelations(ContentInfo $contentInfo): iterable
     {
         return $this->service->loadReverseRelations($contentInfo);
     }
@@ -201,32 +203,32 @@ public function loadReverseRelationList(ContentInfo $contentInfo, int $offset =
         return $this->service->loadReverseRelationList($contentInfo, $offset, $limit);
     }
 
-    public function addRelation(VersionInfo $sourceVersion, ContentInfo $destinationContent)
+    public function addRelation(VersionInfo $sourceVersion, ContentInfo $destinationContent): Relation
     {
         return $this->service->addRelation($sourceVersion, $destinationContent);
     }
 
-    public function deleteRelation(VersionInfo $sourceVersion, ContentInfo $destinationContent)
+    public function deleteRelation(VersionInfo $sourceVersion, ContentInfo $destinationContent): void
     {
-        return $this->service->deleteRelation($sourceVersion, $destinationContent);
+        $this->service->deleteRelation($sourceVersion, $destinationContent);
     }
 
-    public function removeTranslation(ContentInfo $contentInfo, $languageCode)
+    public function removeTranslation(ContentInfo $contentInfo, string $languageCode): void
     {
-        return $this->service->removeTranslation($contentInfo, $languageCode);
+        $this->service->removeTranslation($contentInfo, $languageCode);
     }
 
-    public function deleteTranslation(ContentInfo $contentInfo, $languageCode)
+    public function deleteTranslation(ContentInfo $contentInfo, string $languageCode): void
     {
-        return $this->service->deleteTranslation($contentInfo, $languageCode);
+        $this->service->deleteTranslation($contentInfo, $languageCode);
     }
 
-    public function deleteTranslationFromDraft(VersionInfo $versionInfo, $languageCode)
+    public function deleteTranslationFromDraft(VersionInfo $versionInfo, string $languageCode): Content
     {
         return $this->service->deleteTranslationFromDraft($versionInfo, $languageCode);
     }
 
-    public function loadContentListByContentInfo(array $contentInfoList, array $languages = null, $useAlwaysAvailable = null)
+    public function loadContentListByContentInfo(array $contentInfoList, array $languages = null, bool $useAlwaysAvailable = true): iterable
     {
         return $this->service->loadContentListByContentInfo(
             $contentInfoList,
@@ -245,17 +247,17 @@ public function revealContent(ContentInfo $contentInfo): void
         $this->service->revealContent($contentInfo);
     }
 
-    public function newContentCreateStruct(ContentType $contentType, $mainLanguageCode)
+    public function newContentCreateStruct(ContentType $contentType, string $mainLanguageCode): ContentCreateStruct
     {
         return $this->service->newContentCreateStruct($contentType, $mainLanguageCode);
     }
 
-    public function newContentMetadataUpdateStruct()
+    public function newContentMetadataUpdateStruct(): ContentMetadataUpdateStruct
     {
         return $this->service->newContentMetadataUpdateStruct();
     }
 
-    public function newContentUpdateStruct()
+    public function newContentUpdateStruct(): ContentUpdateStruct
     {
         return $this->service->newContentUpdateStruct();
     }
diff --git a/eZ/Publish/Core/Repository/SiteAccessAware/Tests/ContentServiceTest.php b/eZ/Publish/Core/Repository/SiteAccessAware/Tests/ContentServiceTest.php
index 214c90e1faa..87038c12c32 100644
--- a/eZ/Publish/Core/Repository/SiteAccessAware/Tests/ContentServiceTest.php
+++ b/eZ/Publish/Core/Repository/SiteAccessAware/Tests/ContentServiceTest.php
@@ -9,6 +9,7 @@
 use eZ\Publish\API\Repository\Values\Content\ContentMetadataUpdateStruct;
 use eZ\Publish\API\Repository\Values\Content\Language;
 use eZ\Publish\API\Repository\Values\Content\LocationCreateStruct;
+use eZ\Publish\API\Repository\Values\Content\Relation;
 use eZ\Publish\API\Repository\Values\Content\RelationList;
 use eZ\Publish\Core\Repository\Values\ContentType\ContentType;
 use eZ\Publish\Core\Repository\Values\User\User;
@@ -34,6 +35,7 @@ public function providerForPassTroughMethods()
         $contentInfo = new ContentInfo();
         $versionInfo = new VersionInfo();
         $content = $this->createMock(Content::class);
+        $relation = $this->createMock(Relation::class);
         $relationList = new RelationList();
         $contentCreateStruct = new ContentCreateStruct();
         $contentUpdateStruct = new ContentUpdateStruct();
@@ -45,95 +47,96 @@ public function providerForPassTroughMethods()
 
         // string $method, array $arguments, bool $return = true
         return [
-            ['loadContentInfo', [42]],
+            ['loadContentInfo', [42], $contentInfo],
             ['loadContentInfoList', [[42]], [$contentInfo]],
 
-            ['loadContentInfoByRemoteId', ['f348tj4gorgji4']],
+            ['loadContentInfoByRemoteId', ['f348tj4gorgji4'], $contentInfo],
 
-            ['loadVersionInfo', [$contentInfo]],
-            ['loadVersionInfo', [$contentInfo, 3]],
+            ['loadVersionInfo', [$contentInfo], $versionInfo],
+            ['loadVersionInfo', [$contentInfo, 3], $versionInfo],
 
-            ['loadVersionInfoById', [42]],
-            ['loadVersionInfoById', [42, 3]],
+            ['loadVersionInfoById', [42], $versionInfo],
+            ['loadVersionInfoById', [42, 3], $versionInfo],
 
-            ['createContent', [$contentCreateStruct]],
-            ['createContent', [$contentCreateStruct, [44]]],
+            ['createContent', [$contentCreateStruct], $content],
+            ['createContent', [$contentCreateStruct, [44]], $content],
 
-            ['updateContentMetadata', [$contentInfo, $contentMetaStruct]],
+            ['updateContentMetadata', [$contentInfo, $contentMetaStruct], $content],
 
-            ['deleteContent', [$contentInfo]],
+            ['deleteContent', [$contentInfo], null],
 
-            ['createContentDraft', [$contentInfo]],
-            ['createContentDraft', [$contentInfo, $versionInfo]],
-            ['createContentDraft', [$contentInfo, $versionInfo, $user]],
-            ['createContentDraft', [$contentInfo, $versionInfo, $user, $language]],
+            ['createContentDraft', [$contentInfo], $content],
+            ['createContentDraft', [$contentInfo, $versionInfo], $content],
+            ['createContentDraft', [$contentInfo, $versionInfo, $user], $content],
+            ['createContentDraft', [$contentInfo, $versionInfo, $user, $language], $content],
 
             ['countContentDrafts', [], 0],
             ['countContentDrafts', [$user], 0],
 
-            ['loadContentDrafts', []],
-            ['loadContentDrafts', [$user]],
+            ['loadContentDrafts', [], [$content]],
+            ['loadContentDrafts', [$user], [$content]],
 
             ['loadContentDraftList', [], new ContentDraftList()],
             ['loadContentDraftList', [$user], new ContentDraftList()],
             ['loadContentDraftList', [$user, 1], new ContentDraftList()],
             ['loadContentDraftList', [$user, 1, 25], new ContentDraftList()],
 
-            ['updateContent', [$versionInfo, $contentUpdateStruct]],
+            ['updateContent', [$versionInfo, $contentUpdateStruct], $content],
 
-            ['publishVersion', [$versionInfo]],
+            ['publishVersion', [$versionInfo], $content],
 
-            ['deleteVersion', [$versionInfo]],
+            ['deleteVersion', [$versionInfo], null],
 
-            ['loadVersions', [$contentInfo]],
+            ['loadVersions', [$contentInfo], [$versionInfo]],
 
-            ['copyContent', [$contentInfo, $locationCreateStruct]],
-            ['copyContent', [$contentInfo, $locationCreateStruct, $versionInfo]],
+            ['copyContent', [$contentInfo, $locationCreateStruct], $content],
+            ['copyContent', [$contentInfo, $locationCreateStruct, $versionInfo], $content],
 
-            ['loadRelations', [$versionInfo]],
+            ['loadRelations', [$versionInfo], [$relation]],
 
             ['countReverseRelations', [$contentInfo], 0],
 
             ['loadReverseRelations', [$contentInfo], $relationList],
             ['loadReverseRelationList', [$contentInfo], $relationList],
 
-            ['addRelation', [$versionInfo, $contentInfo]],
+            ['addRelation', [$versionInfo, $contentInfo], null],
 
-            ['deleteRelation', [$versionInfo, $contentInfo]],
+            ['deleteRelation', [$versionInfo, $contentInfo], null],
 
-            ['removeTranslation', [$contentInfo, 'eng-GB']],
+            ['removeTranslation', [$contentInfo, 'eng-GB'], null],
 
-            ['deleteTranslation', [$contentInfo, 'eng-GB']],
+            ['deleteTranslation', [$contentInfo, 'eng-GB'], null],
 
-            ['deleteTranslationFromDraft', [$versionInfo, 'eng-GB']],
+            ['deleteTranslationFromDraft', [$versionInfo, 'eng-GB'], $content],
 
             ['hideContent', [$contentInfo], null],
             ['revealContent', [$contentInfo], null],
 
-            ['newContentCreateStruct', [$contentType, 'eng-GB']],
-            ['newContentMetadataUpdateStruct', []],
-            ['newContentUpdateStruct', []],
+            ['newContentCreateStruct', [$contentType, 'eng-GB'], $contentCreateStruct],
+            ['newContentMetadataUpdateStruct', [], $contentMetaStruct],
+            ['newContentUpdateStruct', [], $contentUpdateStruct],
         ];
     }
 
     public function providerForLanguagesLookupMethods()
     {
+        $content = $this->createMock(Content::class);
         $contentInfo = new ContentInfo();
         $versionInfo = new VersionInfo();
 
         // string $method, array $arguments, bool $return, int $languageArgumentIndex
         return [
-            ['loadContentByContentInfo', [$contentInfo], true, 1],
-            ['loadContentByContentInfo', [$contentInfo, self::LANG_ARG, 4, false], true, 1],
+            ['loadContentByContentInfo', [$contentInfo], $content, 1],
+            ['loadContentByContentInfo', [$contentInfo, self::LANG_ARG, 4, false], $content, 1],
 
-            ['loadContentByVersionInfo', [$versionInfo], true, 1],
-            ['loadContentByVersionInfo', [$versionInfo, self::LANG_ARG, false], true, 1],
+            ['loadContentByVersionInfo', [$versionInfo], $content, 1],
+            ['loadContentByVersionInfo', [$versionInfo, self::LANG_ARG, false], $content, 1],
 
-            ['loadContent', [42], true, 1],
-            ['loadContent', [42, self::LANG_ARG, 4, false], true, 1],
+            ['loadContent', [42], $content, 1],
+            ['loadContent', [42, self::LANG_ARG, 4, false], $content, 1],
 
-            ['loadContentByRemoteId', ['f348tj4gorgji4'], true, 1],
-            ['loadContentByRemoteId', ['f348tj4gorgji4', self::LANG_ARG, 4, false], true, 1],
+            ['loadContentByRemoteId', ['f348tj4gorgji4'], $content, 1],
+            ['loadContentByRemoteId', ['f348tj4gorgji4', self::LANG_ARG, 4, false], $content, 1],
 
             ['loadContentListByContentInfo', [[$contentInfo]], [], 1],
             ['loadContentListByContentInfo', [[$contentInfo], self::LANG_ARG, false], [], 1],
diff --git a/eZ/Publish/Core/Repository/Tests/Service/Mock/ContentTest.php b/eZ/Publish/Core/Repository/Tests/Service/Mock/ContentTest.php
index 76250a346c8..925e1d294ae 100644
--- a/eZ/Publish/Core/Repository/Tests/Service/Mock/ContentTest.php
+++ b/eZ/Publish/Core/Repository/Tests/Service/Mock/ContentTest.php
@@ -195,7 +195,7 @@ public function testLoadVersionInfoByIdAndVersionNumber()
      */
     public function testLoadVersionInfoByIdThrowsNotFoundException()
     {
-        $this->expectException(\eZ\Publish\Core\Base\Exceptions\NotFoundException::class);
+        $this->expectException(NotFoundException::class);
 
         $contentServiceMock = $this->getPartlyMockedContentService(['loadContentInfo']);
         /** @var \PHPUnit\Framework\MockObject\MockObject $contentHandler */
@@ -368,6 +368,8 @@ public function testLoadVersionInfoByIdNonPublishedVersion()
      */
     public function testLoadVersionInfo()
     {
+        $expectedResult = $this->createMock(VersionInfo::class);
+
         $contentServiceMock = $this->getPartlyMockedContentService(
             ['loadVersionInfoById']
         );
@@ -379,7 +381,7 @@ public function testLoadVersionInfo()
             $this->equalTo(42),
             $this->equalTo(7)
         )->will(
-            $this->returnValue('result')
+            $this->returnValue($expectedResult)
         );
 
         $result = $contentServiceMock->loadVersionInfo(
@@ -387,12 +389,12 @@ public function testLoadVersionInfo()
             7
         );
 
-        $this->assertEquals('result', $result);
+        $this->assertEquals($expectedResult, $result);
     }
 
     public function testLoadContent()
     {
-        $contentService = $this->getPartlyMockedContentService(['internalLoadContent']);
+        $contentService = $this->getPartlyMockedContentService(['internalLoadContentById']);
         $content = $this->createMock(APIContent::class);
         $versionInfo = $this->createMock(APIVersionInfo::class);
         $permissionResolver = $this->getPermissionResolverMock();
@@ -408,7 +410,7 @@ public function testLoadContent()
         $contentId = 123;
         $contentService
             ->expects($this->once())
-            ->method('internalLoadContent')
+            ->method('internalLoadContentById')
             ->with($contentId)
             ->will($this->returnValue($content));
 
@@ -423,7 +425,7 @@ public function testLoadContent()
 
     public function testLoadContentNonPublished()
     {
-        $contentService = $this->getPartlyMockedContentService(['internalLoadContent']);
+        $contentService = $this->getPartlyMockedContentService(['internalLoadContentById']);
         $content = $this->createMock(APIContent::class);
         $versionInfo = $this->createMock(APIVersionInfo::class);
         $permissionResolver = $this->getPermissionResolverMock();
@@ -435,7 +437,7 @@ public function testLoadContentNonPublished()
         $contentId = 123;
         $contentService
             ->expects($this->once())
-            ->method('internalLoadContent')
+            ->method('internalLoadContentById')
             ->with($contentId)
             ->will($this->returnValue($content));
 
@@ -460,12 +462,12 @@ public function testLoadContentUnauthorized()
 
         $permissionResolver = $this->getPermissionResolverMock();
 
-        $contentService = $this->getPartlyMockedContentService(['internalLoadContent']);
+        $contentService = $this->getPartlyMockedContentService(['internalLoadContentById']);
         $content = $this->createMock(APIContent::class);
         $contentId = 123;
         $contentService
             ->expects($this->once())
-            ->method('internalLoadContent')
+            ->method('internalLoadContentById')
             ->with($contentId)
             ->will($this->returnValue($content));
 
@@ -483,7 +485,7 @@ public function testLoadContentNotPublishedStatusUnauthorized()
         $this->expectException(\eZ\Publish\Core\Base\Exceptions\UnauthorizedException::class);
 
         $permissionResolver = $this->getPermissionResolverMock();
-        $contentService = $this->getPartlyMockedContentService(['internalLoadContent']);
+        $contentService = $this->getPartlyMockedContentService(['internalLoadContentById']);
         $content = $this->createMock(APIContent::class);
         $versionInfo = $this
             ->getMockBuilder(APIVersionInfo::class)
@@ -495,7 +497,7 @@ public function testLoadContentNotPublishedStatusUnauthorized()
         $contentId = 123;
         $contentService
             ->expects($this->once())
-            ->method('internalLoadContent')
+            ->method('internalLoadContentById')
             ->with($contentId)
             ->will($this->returnValue($content));
 
@@ -515,82 +517,134 @@ public function testLoadContentNotPublishedStatusUnauthorized()
     }
 
     /**
-     * @dataProvider internalLoadContentProvider
+     * @dataProvider internalLoadContentProviderById
      */
-    public function testInternalLoadContent($id, $languages, $versionNo, $isRemoteId, $useAlwaysAvailable)
+    public function testInternalLoadContentById(int $id, ?array $languages, ?int $versionNo, bool $useAlwaysAvailable): void
     {
-        $contentService = $this->getPartlyMockedContentService();
+        if (!empty($languages) && $useAlwaysAvailable) {
+            $spiContentInfo = new SPIContentInfo(['id' => $id, 'alwaysAvailable' => false]);
+        } else {
+            $spiContentInfo = new SPIContentInfo(['id' => $id]);
+        }
+
+        $spiContent = new SPIContent([
+            'versionInfo' => new VersionInfo([
+                'contentInfo' => new ContentInfo([
+                    'id' => 42,
+                    'contentTypeId' => 123,
+                ]),
+            ]),
+        ]);
+
         /** @var \PHPUnit\Framework\MockObject\MockObject $contentHandler */
         $contentHandler = $this->getPersistenceMock()->contentHandler();
-        $realId = $id;
-
-        if ($isRemoteId) {
-            $realId = 123;
-            $spiContentInfo = new SPIContentInfo(['currentVersionNo' => $versionNo ?: 7, 'id' => $realId]);
-            $contentHandler
-                ->expects($this->once())
-                ->method('loadContentInfoByRemoteId')
-                ->with($id)
-                ->will($this->returnValue($spiContentInfo));
-        } elseif (!empty($languages) && $useAlwaysAvailable) {
-            $spiContentInfo = new SPIContentInfo(['alwaysAvailable' => false]);
-            $contentHandler
-                ->expects($this->once())
-                ->method('loadContentInfo')
-                ->with($id)
-                ->will($this->returnValue($spiContentInfo));
-        }
+        $contentHandler
+            ->expects($this->once())
+            ->method('loadContentInfo')
+            ->with($id)
+            ->will($this->returnValue($spiContentInfo));
+
+        $contentHandler
+            ->expects($this->once())
+            ->method('load')
+            ->with($id, $versionNo, $languages)
+            ->willReturn($spiContent);
+
+        $contentService = $this->getPartlyMockedContentService();
+
+        $expectedContent = $this->mockBuildContentDomainObject($spiContent, $languages);
+        $actualContent = $contentService->internalLoadContentById($id, $languages, $versionNo, $useAlwaysAvailable);
+
+        $this->assertSame($expectedContent, $actualContent);
+    }
+
+    /**
+     * @dataProvider internalLoadContentProviderByRemoteId
+     */
+    public function testInternalLoadContentByRemoteId(string $remoteId, ?array $languages, ?int $versionNo, bool $useAlwaysAvailable)
+    {
+        $realId = 123;
+
+        $spiContentInfo = new SPIContentInfo([
+            'currentVersionNo' => $versionNo ?: 7,
+            'id' => $realId,
+        ]);
 
         $spiContent = new SPIContent([
             'versionInfo' => new VersionInfo([
-                    'contentInfo' => new ContentInfo(['id' => 42, 'contentTypeId' => 123]),
+                'contentInfo' => new ContentInfo(['id' => 42, 'contentTypeId' => 123]),
             ]),
         ]);
+
+        $contentService = $this->getPartlyMockedContentService();
+        /** @var \PHPUnit\Framework\MockObject\MockObject $contentHandler */
+        $contentHandler = $this->getPersistenceMock()->contentHandler();
+        $contentHandler
+            ->expects($this->once())
+            ->method('loadContentInfoByRemoteId')
+            ->with($remoteId)
+            ->will($this->returnValue($spiContentInfo));
+
         $contentHandler
             ->expects($this->once())
             ->method('load')
             ->with($realId, $versionNo, $languages)
             ->willReturn($spiContent);
 
-        $content = $this->mockBuildContentDomainObject($spiContent, $languages);
+        $expectedContent = $this->mockBuildContentDomainObject($spiContent, $languages);
 
-        $this->assertSame(
-            $content,
-            $contentService->internalLoadContent($id, $languages, $versionNo, $isRemoteId, $useAlwaysAvailable)
+        $actualContent = $contentService->internalLoadContentByRemoteId(
+            $remoteId,
+            $languages,
+            $versionNo,
+            $useAlwaysAvailable
         );
+
+        $this->assertSame($expectedContent, $actualContent);
     }
 
-    public function internalLoadContentProvider()
+    public function internalLoadContentProviderById(): array
     {
         return [
-            [123, null, null, false, false],
-            [123, null, 456, false, false],
-            [456, null, 123, false, true],
-            [456, null, 2, false, false],
-            [456, ['eng-GB'], 2, false, true],
-            [456, ['eng-GB', 'fre-FR'], null, false, false],
-            [456, ['eng-GB', 'fre-FR', 'nor-NO'], 2, false, false],
-            // With remoteId
-            [123, null, null, true, false],
-            ['someRemoteId', null, 456, true, false],
-            [456, null, 123, true, false],
-            ['someRemoteId', null, 2, true, false],
-            ['someRemoteId', ['eng-GB'], 2, true, false],
-            [456, ['eng-GB', 'fre-FR'], null, true, false],
-            ['someRemoteId', ['eng-GB', 'fre-FR', 'nor-NO'], 2, true, false],
+            [123, null, null, false],
+            [123, null, 456, false],
+            [456, null, 123, true],
+            [456, null, 2, false],
+            [456, ['eng-GB'], 2, true],
+            [456, ['eng-GB', 'fre-FR'], null, false],
+            [456, ['eng-GB', 'fre-FR', 'nor-NO'], 2, false],
         ];
     }
 
-    public function testInternalLoadContentNotFound()
+    public function internalLoadContentProviderByRemoteId(): array
     {
-        $this->expectException(\eZ\Publish\Core\Base\Exceptions\NotFoundException::class);
+        return [
+            ['123', null, null, false],
+            ['someRemoteId', null, 456, false],
+            ['456', null, 123, false],
+            ['someRemoteId', null, 2, false],
+            ['someRemoteId', ['eng-GB'], 2, false],
+            ['456', ['eng-GB', 'fre-FR'], null, false],
+            ['someRemoteId', ['eng-GB', 'fre-FR', 'nor-NO'], 2, false],
+        ];
+    }
+
+    public function testInternalLoadContentByIdNotFound(): void
+    {
+        $this->expectException(NotFoundException::class);
 
-        $contentService = $this->getPartlyMockedContentService();
-        /** @var \PHPUnit\Framework\MockObject\MockObject $contentHandler */
-        $contentHandler = $this->getPersistenceMock()->contentHandler();
         $id = 123;
         $versionNo = 7;
         $languages = null;
+
+        /** @var \PHPUnit\Framework\MockObject\MockObject $contentHandler */
+        $contentHandler = $this->getPersistenceMock()->contentHandler();
+        $contentHandler
+            ->expects($this->once())
+            ->method('loadContentInfo')
+            ->with($id)
+            ->willReturn(new SPIContent\ContentInfo(['id' => $id]));
+
         $contentHandler
             ->expects($this->once())
             ->method('load')
@@ -601,7 +655,37 @@ public function testInternalLoadContentNotFound()
                 )
             );
 
-        $contentService->internalLoadContent($id, $languages, $versionNo);
+        $contentService = $this->getPartlyMockedContentService();
+        $contentService->internalLoadContentById($id, $languages, $versionNo);
+    }
+
+    public function testInternalLoadContentByRemoteIdNotFound(): void
+    {
+        $this->expectException(NotFoundException::class);
+
+        $remoteId = 'dca290623518d393126d3408b45af6ee';
+        $id = 123;
+        $versionNo = 7;
+        $languages = null;
+
+        /** @var \PHPUnit\Framework\MockObject\MockObject $contentHandler */
+        $contentHandler = $this->getPersistenceMock()->contentHandler();
+        $contentHandler
+            ->expects($this->once())
+            ->method('loadContentInfoByRemoteId')
+            ->with($remoteId)
+            ->willReturn(new SPIContent\ContentInfo(['id' => $id]));
+
+        $contentHandler
+            ->expects($this->once())
+            ->method('load')
+            ->with($id, $versionNo, $languages)
+            ->willThrowException(
+                $this->createMock(APINotFoundException::class)
+            );
+
+        $contentService = $this->getPartlyMockedContentService();
+        $contentService->internalLoadContentByRemoteId($remoteId, $languages, $versionNo);
     }
 
     /**
@@ -611,6 +695,8 @@ public function testInternalLoadContentNotFound()
      */
     public function testLoadContentByContentInfo()
     {
+        $expectedResult = $this->createMock(Content::class);
+
         $contentServiceMock = $this->getPartlyMockedContentService(
             ['loadContent']
         );
@@ -624,7 +710,7 @@ public function testLoadContentByContentInfo()
             $this->equalTo(7),
             $this->equalTo(false)
         )->will(
-            $this->returnValue('result')
+            $this->returnValue($expectedResult)
         );
 
         $result = $contentServiceMock->loadContentByContentInfo(
@@ -633,7 +719,7 @@ public function testLoadContentByContentInfo()
             7
         );
 
-        $this->assertEquals('result', $result);
+        $this->assertEquals($expectedResult, $result);
     }
 
     /**
@@ -643,6 +729,8 @@ public function testLoadContentByContentInfo()
      */
     public function testLoadContentByVersionInfo()
     {
+        $expectedResult = $this->createMock(Content::class);
+
         $contentServiceMock = $this->getPartlyMockedContentService(
             ['loadContent']
         );
@@ -656,7 +744,7 @@ public function testLoadContentByVersionInfo()
             $this->equalTo(7),
             $this->equalTo(false)
         )->will(
-            $this->returnValue('result')
+            $this->returnValue($expectedResult)
         );
 
         $result = $contentServiceMock->loadContentByVersionInfo(
@@ -669,7 +757,7 @@ public function testLoadContentByVersionInfo()
             ['cro-HR']
         );
 
-        $this->assertEquals('result', $result);
+        $this->assertEquals($expectedResult, $result);
     }
 
     /**
@@ -682,7 +770,7 @@ public function testDeleteContentThrowsUnauthorizedException()
         $this->expectException(\eZ\Publish\Core\Base\Exceptions\UnauthorizedException::class);
 
         $permissionResolver = $this->getPermissionResolverMock();
-        $contentService = $this->getPartlyMockedContentService(['internalLoadContentInfo']);
+        $contentService = $this->getPartlyMockedContentService(['internalLoadContentInfoById']);
         $contentInfo = $this->createMock(APIContentInfo::class);
 
         $contentInfo->expects($this->any())
@@ -691,7 +779,7 @@ public function testDeleteContentThrowsUnauthorizedException()
             ->will($this->returnValue(42));
 
         $contentService->expects($this->once())
-            ->method('internalLoadContentInfo')
+            ->method('internalLoadContentInfoById')
             ->with(42)
             ->will($this->returnValue($contentInfo));
 
@@ -719,7 +807,7 @@ public function testDeleteContent()
             ->with('content', 'remove')
             ->will($this->returnValue(true));
 
-        $contentService = $this->getPartlyMockedContentService(['internalLoadContentInfo']);
+        $contentService = $this->getPartlyMockedContentService(['internalLoadContentInfoById']);
         /** @var \PHPUnit\Framework\MockObject\MockObject $urlAliasHandler */
         $urlAliasHandler = $this->getPersistenceMock()->urlAliasHandler();
         /** @var \PHPUnit\Framework\MockObject\MockObject $locationHandler */
@@ -730,7 +818,7 @@ public function testDeleteContent()
         $contentInfo = $this->createMock(APIContentInfo::class);
 
         $contentService->expects($this->once())
-            ->method('internalLoadContentInfo')
+            ->method('internalLoadContentInfoById')
             ->with(42)
             ->will($this->returnValue($contentInfo));
 
@@ -783,14 +871,14 @@ public function testDeleteContentWithRollback()
             ->with('content', 'remove')
             ->will($this->returnValue(true));
 
-        $contentService = $this->getPartlyMockedContentService(['internalLoadContentInfo']);
+        $contentService = $this->getPartlyMockedContentService(['internalLoadContentInfoById']);
         /** @var \PHPUnit\Framework\MockObject\MockObject $locationHandler */
         $locationHandler = $this->getPersistenceMock()->locationHandler();
 
         $contentInfo = $this->createMock(APIContentInfo::class);
 
         $contentService->expects($this->once())
-            ->method('internalLoadContentInfo')
+            ->method('internalLoadContentInfoById')
             ->with(42)
             ->will($this->returnValue($contentInfo));
 
@@ -1020,7 +1108,7 @@ public function testCreateContentThrowsInvalidArgumentExceptionDuplicateRemoteId
         $mockedService->expects($this->once())
             ->method('loadContentByRemoteId')
             ->with($contentCreateStruct->remoteId)
-            ->will($this->returnValue('Hello...'));
+            ->will($this->returnValue($this->createMock(Content::class)));
 
         $mockedService->createContent(
             new ContentCreateStruct(
@@ -1365,7 +1453,8 @@ function (ValueStub $value) use ($emptyValue) {
                 ->with(
                     $this->isInstanceOf(SPIContent::class),
                     $this->equalTo($contentType)
-                );
+                )
+                ->willReturn($this->createMock(APIContent::class));
 
             $mockedService->createContent($contentCreateStruct, []);
         }
@@ -2541,7 +2630,8 @@ public function testCreateContentWithLocations()
             ->with(
                 $this->isInstanceOf(SPIContent::class),
                 $this->isInstanceOf(APIContentType::class)
-            );
+            )
+            ->willReturn($this->createMock(APIContent::class));
 
         $repositoryMock->expects($this->once())->method('commit');
 
@@ -2778,7 +2868,8 @@ public function testCreateContentObjectStates()
             ->with(
                 $this->isInstanceOf(SPIContent::class),
                 $this->isInstanceOf(APIContentType::class)
-            );
+            )
+            ->willReturn($this->createMock(APIContent::class));
 
         $repositoryMock->expects($this->once())->method('commit');
 
@@ -3310,7 +3401,8 @@ function (ValueStub $value) use ($emptyValue) {
                 ->with(
                     $this->isInstanceOf(SPIContent::class),
                     $this->isInstanceOf(APIContentType::class)
-                );
+                )
+                ->willReturn($this->createMock(APIContent::class));
 
             $mockedService->updateContent($content->versionInfo, $contentUpdateStruct);
         }
@@ -5452,7 +5544,7 @@ public function testCopyContent()
         $repositoryMock = $this->getRepositoryMock();
         $contentService = $this->getPartlyMockedContentService([
             'internalLoadContentInfo',
-            'internalLoadContent',
+            'internalLoadContentById',
             'getUnixTimestamp',
         ]);
         $locationServiceMock = $this->getLocationServiceMock();
@@ -5558,7 +5650,7 @@ public function testCopyContent()
             );
 
         $contentService->expects($this->once())
-            ->method('internalLoadContent')
+            ->method('internalLoadContentById')
             ->with(
                 $content->id
             )
@@ -5583,8 +5675,7 @@ public function testCopyContentWithVersionInfo()
     {
         $repositoryMock = $this->getRepositoryMock();
         $contentService = $this->getPartlyMockedContentService([
-            'internalLoadContentInfo',
-            'internalLoadContent',
+            'internalLoadContentById',
             'getUnixTimestamp',
         ]);
         $locationServiceMock = $this->getLocationServiceMock();
@@ -5687,7 +5778,7 @@ public function testCopyContentWithVersionInfo()
             );
 
         $contentService->expects($this->once())
-            ->method('internalLoadContent')
+            ->method('internalLoadContentById')
             ->with(
                 $content->id
             )
diff --git a/eZ/Publish/Core/Repository/Tests/Service/Mock/SearchTest.php b/eZ/Publish/Core/Repository/Tests/Service/Mock/SearchTest.php
index d06b74450be..77b692ed20f 100644
--- a/eZ/Publish/Core/Repository/Tests/Service/Mock/SearchTest.php
+++ b/eZ/Publish/Core/Repository/Tests/Service/Mock/SearchTest.php
@@ -630,11 +630,12 @@ public function testFindSingle()
             ->will($this->returnValue(true));
 
         $languageFilter = [];
-        $spiContentInfo = new SPIContentInfo();
+        $spiContentInfo = new SPIContentInfo(['id' => 123]);
         $contentMock = $this->getMockForAbstractClass(Content::class);
 
         /* @var \PHPUnit\Framework\MockObject\MockObject $searchHandlerMock */
-        $searchHandlerMock->expects($this->once())
+        $searchHandlerMock
+            ->expects($this->once())
             ->method('findSingle')
             ->with($this->equalTo($criterionMock), $this->equalTo($languageFilter))
             ->will($this->returnValue($spiContentInfo));
@@ -644,7 +645,7 @@ public function testFindSingle()
 
         $contentServiceMock
             ->expects($this->once())
-            ->method('internalLoadContent')
+            ->method('internalLoadContentById')
             ->will($this->returnValue($contentMock));
 
         $result = $service->findSingle($criterionMock, $languageFilter, true);
diff --git a/eZ/Publish/Core/Repository/TrashService.php b/eZ/Publish/Core/Repository/TrashService.php
index dbb2cdb5e63..e6b4dcf1d87 100644
--- a/eZ/Publish/Core/Repository/TrashService.php
+++ b/eZ/Publish/Core/Repository/TrashService.php
@@ -102,7 +102,7 @@ public function loadTrashItem(int $trashItemId): APITrashItem
         $spiTrashItem = $this->persistenceHandler->trashHandler()->loadTrashItem($trashItemId);
         $trash = $this->buildDomainTrashItemObject(
             $spiTrashItem,
-            $this->repository->getContentService()->internalLoadContent($spiTrashItem->contentId)
+            $this->repository->getContentService()->internalLoadContentById($spiTrashItem->contentId)
         );
         if (!$this->permissionResolver->canUser('content', 'read', $trash->getContentInfo())) {
             throw new UnauthorizedException('content', 'read');
@@ -152,7 +152,7 @@ public function trash(Location $location): ?APITrashItem
             return isset($spiTrashItem)
                 ? $this->buildDomainTrashItemObject(
                     $spiTrashItem,
-                    $this->repository->getContentService()->internalLoadContent($spiTrashItem->contentId)
+                    $this->repository->getContentService()->internalLoadContentById($spiTrashItem->contentId)
                 )
                 : null;
         } catch (Exception $e) {
diff --git a/eZ/Publish/Core/Repository/UserService.php b/eZ/Publish/Core/Repository/UserService.php
index 63b9eea242a..b597c94cda0 100644
--- a/eZ/Publish/Core/Repository/UserService.php
+++ b/eZ/Publish/Core/Repository/UserService.php
@@ -226,7 +226,7 @@ public function loadSubUserGroups(APIUserGroup $userGroup, $offset = 0, $limit =
         $subUserGroups = [];
         foreach ($searchResult->searchHits as $searchHit) {
             $subUserGroups[] = $this->buildDomainUserGroupObject(
-                $this->repository->getContentService()->internalLoadContent(
+                $this->repository->getContentService()->internalLoadContentById(
                     $searchHit->valueObject->contentInfo->id,
                     $prioritizedLanguages
                 )
@@ -466,7 +466,7 @@ public function createUser(APIUserCreateStruct $userCreateStruct, array $parentG
     public function loadUser($userId, array $prioritizedLanguages = [])
     {
         /** @var \eZ\Publish\API\Repository\Values\Content\Content $content */
-        $content = $this->repository->getContentService()->internalLoadContent($userId, $prioritizedLanguages);
+        $content = $this->repository->getContentService()->internalLoadContentById($userId, $prioritizedLanguages);
         // Get spiUser value from Field Value
         foreach ($content->getFields() as $field) {
             if (!$field->value instanceof UserValue) {
@@ -986,7 +986,7 @@ public function loadUserGroupsOfUser(APIUser $user, $offset = 0, $limit = 25, ar
         $userGroups = [];
         foreach ($searchResult->searchHits as $resultItem) {
             $userGroups[] = $this->buildDomainUserGroupObject(
-                $this->repository->getContentService()->internalLoadContent(
+                $this->repository->getContentService()->internalLoadContentById(
                     $resultItem->valueObject->contentInfo->id,
                     $prioritizedLanguages
                 )
@@ -1044,7 +1044,7 @@ public function loadUsersOfUserGroup(
         foreach ($searchResult->searchHits as $resultItem) {
             $users[] = $this->buildDomainUserObject(
                 $this->userHandler->load($resultItem->valueObject->contentInfo->id),
-                $this->repository->getContentService()->internalLoadContent(
+                $this->repository->getContentService()->internalLoadContentById(
                     $resultItem->valueObject->contentInfo->id,
                     $prioritizedLanguages
                 )
@@ -1271,7 +1271,7 @@ protected function buildDomainUserObject(
         array $prioritizedLanguages = []
     ) {
         if ($content === null) {
-            $content = $this->repository->getContentService()->internalLoadContent(
+            $content = $this->repository->getContentService()->internalLoadContentById(
                 $spiUser->id,
                 $prioritizedLanguages
             );
diff --git a/eZ/Publish/SPI/Repository/Decorator/ContentServiceDecorator.php b/eZ/Publish/SPI/Repository/Decorator/ContentServiceDecorator.php
index b654f6836a9..43a1b401935 100644
--- a/eZ/Publish/SPI/Repository/Decorator/ContentServiceDecorator.php
+++ b/eZ/Publish/SPI/Repository/Decorator/ContentServiceDecorator.php
@@ -33,7 +33,7 @@ public function __construct(ContentService $innerService)
         $this->innerService = $innerService;
     }
 
-    public function loadContentInfo($contentId): ContentInfo
+    public function loadContentInfo(int $contentId): ContentInfo
     {
         return $this->innerService->loadContentInfo($contentId);
     }
@@ -43,21 +43,21 @@ public function loadContentInfoList(array $contentIds): iterable
         return $this->innerService->loadContentInfoList($contentIds);
     }
 
-    public function loadContentInfoByRemoteId($remoteId): ContentInfo
+    public function loadContentInfoByRemoteId(string $remoteId): ContentInfo
     {
         return $this->innerService->loadContentInfoByRemoteId($remoteId);
     }
 
     public function loadVersionInfo(
         ContentInfo $contentInfo,
-        $versionNo = null
+        ?int $versionNo = null
     ): VersionInfo {
         return $this->innerService->loadVersionInfo($contentInfo, $versionNo);
     }
 
     public function loadVersionInfoById(
-        $contentId,
-        $versionNo = null
+        int $contentId,
+        ?int $versionNo = null
     ): VersionInfo {
         return $this->innerService->loadVersionInfoById($contentId, $versionNo);
     }
@@ -65,8 +65,8 @@ public function loadVersionInfoById(
     public function loadContentByContentInfo(
         ContentInfo $contentInfo,
         array $languages = null,
-        $versionNo = null,
-        $useAlwaysAvailable = true
+        ?int $versionNo = null,
+        bool $useAlwaysAvailable = true
     ): Content {
         return $this->innerService->loadContentByContentInfo($contentInfo, $languages, $versionNo, $useAlwaysAvailable);
     }
@@ -74,25 +74,25 @@ public function loadContentByContentInfo(
     public function loadContentByVersionInfo(
         VersionInfo $versionInfo,
         array $languages = null,
-        $useAlwaysAvailable = true
+        bool $useAlwaysAvailable = true
     ): Content {
         return $this->innerService->loadContentByVersionInfo($versionInfo, $languages, $useAlwaysAvailable);
     }
 
     public function loadContent(
-        $contentId,
+        int $contentId,
         array $languages = null,
-        $versionNo = null,
-        $useAlwaysAvailable = true
+        ?int $versionNo = null,
+        bool $useAlwaysAvailable = true
     ): Content {
         return $this->innerService->loadContent($contentId, $languages, $versionNo, $useAlwaysAvailable);
     }
 
     public function loadContentByRemoteId(
-        $remoteId,
+        string $remoteId,
         array $languages = null,
-        $versionNo = null,
-        $useAlwaysAvailable = true
+        ?int $versionNo = null,
+        bool $useAlwaysAvailable = true
     ): Content {
         return $this->innerService->loadContentByRemoteId($remoteId, $languages, $versionNo, $useAlwaysAvailable);
     }
@@ -100,8 +100,8 @@ public function loadContentByRemoteId(
     public function loadContentListByContentInfo(
         array $contentInfoList,
         array $languages = [],
-        $useAlwaysAvailable = true
-    ): array {
+        bool $useAlwaysAvailable = true
+    ): iterable {
         return $this->innerService->loadContentListByContentInfo($contentInfoList, $languages, $useAlwaysAvailable);
     }
 
@@ -119,15 +119,15 @@ public function updateContentMetadata(
         return $this->innerService->updateContentMetadata($contentInfo, $contentMetadataUpdateStruct);
     }
 
-    public function deleteContent(ContentInfo $contentInfo): array
+    public function deleteContent(ContentInfo $contentInfo): iterable
     {
         return $this->innerService->deleteContent($contentInfo);
     }
 
     public function createContentDraft(
         ContentInfo $contentInfo,
-        VersionInfo $versionInfo = null,
-        User $creator = null,
+        ?VersionInfo $versionInfo = null,
+        ?User $creator = null,
         ?Language $language = null
     ): Content {
         return $this->innerService->createContentDraft($contentInfo, $versionInfo, $creator, $language);
@@ -138,7 +138,7 @@ public function countContentDrafts(User $user = null): int
         return $this->innerService->countContentDrafts($user);
     }
 
-    public function loadContentDrafts(User $user = null): array
+    public function loadContentDrafts(?User $user = null): iterable
     {
         return $this->innerService->loadContentDrafts($user);
     }
@@ -160,12 +160,12 @@ public function publishVersion(VersionInfo $versionInfo, array $translations = L
         return $this->innerService->publishVersion($versionInfo, $translations);
     }
 
-    public function deleteVersion(VersionInfo $versionInfo)
+    public function deleteVersion(VersionInfo $versionInfo): void
     {
-        return $this->innerService->deleteVersion($versionInfo);
+        $this->innerService->deleteVersion($versionInfo);
     }
 
-    public function loadVersions(ContentInfo $contentInfo, ?int $status = null): array
+    public function loadVersions(ContentInfo $contentInfo, ?int $status = null): iterable
     {
         return $this->innerService->loadVersions($contentInfo, $status);
     }
@@ -173,12 +173,12 @@ public function loadVersions(ContentInfo $contentInfo, ?int $status = null): arr
     public function copyContent(
         ContentInfo $contentInfo,
         LocationCreateStruct $destinationLocationCreateStruct,
-        VersionInfo $versionInfo = null
+        ?VersionInfo $versionInfo = null
     ): Content {
         return $this->innerService->copyContent($contentInfo, $destinationLocationCreateStruct, $versionInfo);
     }
 
-    public function loadRelations(VersionInfo $versionInfo): array
+    public function loadRelations(VersionInfo $versionInfo): iterable
     {
         return $this->innerService->loadRelations($versionInfo);
     }
@@ -188,7 +188,7 @@ public function countReverseRelations(ContentInfo $contentInfo): int
         return $this->innerService->countReverseRelations($contentInfo);
     }
 
-    public function loadReverseRelations(ContentInfo $contentInfo): array
+    public function loadReverseRelations(ContentInfo $contentInfo): iterable
     {
         return $this->innerService->loadReverseRelations($contentInfo);
     }
@@ -208,27 +208,27 @@ public function addRelation(
     public function deleteRelation(
         VersionInfo $sourceVersion,
         ContentInfo $destinationContent
-    ) {
-        return $this->innerService->deleteRelation($sourceVersion, $destinationContent);
+    ): void {
+        $this->innerService->deleteRelation($sourceVersion, $destinationContent);
     }
 
     public function removeTranslation(
         ContentInfo $contentInfo,
-        $languageCode
-    ) {
-        return $this->innerService->removeTranslation($contentInfo, $languageCode);
+        string $languageCode
+    ): void {
+        $this->innerService->removeTranslation($contentInfo, $languageCode);
     }
 
     public function deleteTranslation(
         ContentInfo $contentInfo,
-        $languageCode
-    ) {
-        return $this->innerService->deleteTranslation($contentInfo, $languageCode);
+        string $languageCode
+    ): void {
+        $this->innerService->deleteTranslation($contentInfo, $languageCode);
     }
 
     public function deleteTranslationFromDraft(
         VersionInfo $versionInfo,
-        $languageCode
+        string $languageCode
     ): Content {
         return $this->innerService->deleteTranslationFromDraft($versionInfo, $languageCode);
     }
@@ -245,7 +245,7 @@ public function revealContent(ContentInfo $contentInfo): void
 
     public function newContentCreateStruct(
         ContentType $contentType,
-        $mainLanguageCode
+        string $mainLanguageCode
     ): ContentCreateStruct {
         return $this->innerService->newContentCreateStruct($contentType, $mainLanguageCode);
     }
diff --git a/eZ/Publish/SPI/Repository/Tests/Decorator/ContentServiceDecoratorTest.php b/eZ/Publish/SPI/Repository/Tests/Decorator/ContentServiceDecoratorTest.php
index b26b3c480bf..ce6a76ba039 100644
--- a/eZ/Publish/SPI/Repository/Tests/Decorator/ContentServiceDecoratorTest.php
+++ b/eZ/Publish/SPI/Repository/Tests/Decorator/ContentServiceDecoratorTest.php
@@ -25,6 +25,11 @@
 
 class ContentServiceDecoratorTest extends TestCase
 {
+    private const EXAMPLE_CONTENT_ID = 1;
+    private const EXAMPLE_LANGUAGE_CODE = 'eng-GB';
+    private const EXAMPLE_CONTENT_REMOTE_ID = 'example';
+    private const EXAMPLE_VERSION_NO = 1;
+
     protected function createDecorator(MockObject $service): ContentService
     {
         return new class($service) extends ContentServiceDecorator {
@@ -41,7 +46,7 @@ public function testLoadContentInfoDecorator()
         $serviceMock = $this->createServiceMock();
         $decoratedService = $this->createDecorator($serviceMock);
 
-        $parameters = ['random_value_5ced05ce154118.08177784'];
+        $parameters = [self::EXAMPLE_CONTENT_ID];
 
         $serviceMock->expects($this->once())->method('loadContentInfo')->with(...$parameters)->willReturn($this->createMock(ContentInfo::class));
 
@@ -79,7 +84,7 @@ public function testLoadVersionInfoDecorator()
 
         $parameters = [
             $this->createMock(ContentInfo::class),
-            'random_value_5ced05ce1541e5.29503590',
+            self::EXAMPLE_VERSION_NO,
         ];
 
         $serviceMock->expects($this->once())->method('loadVersionInfo')->with(...$parameters)->willReturn($this->createMock(VersionInfo::class));
@@ -93,8 +98,8 @@ public function testLoadVersionInfoByIdDecorator()
         $decoratedService = $this->createDecorator($serviceMock);
 
         $parameters = [
-            'random_value_5ced05ce154212.71705283',
-            'random_value_5ced05ce154226.14877654',
+            self::EXAMPLE_CONTENT_ID,
+            self::EXAMPLE_VERSION_NO,
         ];
 
         $serviceMock->expects($this->once())->method('loadVersionInfoById')->with(...$parameters)->willReturn($this->createMock(VersionInfo::class));
@@ -109,9 +114,9 @@ public function testLoadContentByContentInfoDecorator()
 
         $parameters = [
             $this->createMock(ContentInfo::class),
-            ['random_value_5ced05ce154263.26527866'],
-            'random_value_5ced05ce154274.48633738',
-            'random_value_5ced05ce154288.12181629',
+            [self::EXAMPLE_LANGUAGE_CODE],
+            self::EXAMPLE_VERSION_NO,
+            true,
         ];
 
         $serviceMock->expects($this->once())->method('loadContentByContentInfo')->with(...$parameters)->willReturn($this->createMock(Content::class));
@@ -126,8 +131,8 @@ public function testLoadContentByVersionInfoDecorator()
 
         $parameters = [
             $this->createMock(VersionInfo::class),
-            ['random_value_5ced05ce154b93.03098248'],
-            'random_value_5ced05ce154bc5.33425740',
+            [self::EXAMPLE_LANGUAGE_CODE],
+            true,
         ];
 
         $serviceMock->expects($this->once())->method('loadContentByVersionInfo')->with(...$parameters)->willReturn($this->createMock(Content::class));
@@ -141,10 +146,10 @@ public function testLoadContentDecorator()
         $decoratedService = $this->createDecorator($serviceMock);
 
         $parameters = [
-            'random_value_5ced05ce154c25.68443488',
-            ['random_value_5ced05ce154c34.23275680'],
-            'random_value_5ced05ce154c41.25945372',
-            'random_value_5ced05ce154c55.22828466',
+            self::EXAMPLE_CONTENT_ID,
+            [self::EXAMPLE_LANGUAGE_CODE],
+            self::EXAMPLE_VERSION_NO,
+            true,
         ];
 
         $serviceMock->expects($this->once())->method('loadContent')->with(...$parameters)->willReturn($this->createMock(Content::class));
@@ -158,10 +163,10 @@ public function testLoadContentByRemoteIdDecorator()
         $decoratedService = $this->createDecorator($serviceMock);
 
         $parameters = [
-            'random_value_5ced05ce154c88.14138266',
-            ['random_value_5ced05ce154c96.62330223'],
-            'random_value_5ced05ce154ca4.47689455',
-            'random_value_5ced05ce154cb6.74747836',
+            self::EXAMPLE_CONTENT_REMOTE_ID,
+            [self::EXAMPLE_LANGUAGE_CODE],
+            self::EXAMPLE_VERSION_NO,
+            true,
         ];
 
         $serviceMock->expects($this->once())->method('loadContentByRemoteId')->with(...$parameters)->willReturn($this->createMock(Content::class));
@@ -175,9 +180,9 @@ public function testLoadContentListByContentInfoDecorator()
         $decoratedService = $this->createDecorator($serviceMock);
 
         $parameters = [
-            ['random_value_5ced05ce154ce0.53430215'],
-            ['random_value_5ced05ce154cf5.73360157'],
-            'random_value_5ced05ce154d01.47432661',
+            [$this->createMock(ContentInfo::class)],
+            [self::EXAMPLE_LANGUAGE_CODE],
+            true,
         ];
 
         $serviceMock->expects($this->once())->method('loadContentListByContentInfo')->with(...$parameters)->willReturn([]);
@@ -289,7 +294,7 @@ public function testDeleteVersionDecorator()
 
         $parameters = [$this->createMock(VersionInfo::class)];
 
-        $serviceMock->expects($this->once())->method('deleteVersion')->with(...$parameters)->willReturn($this->createMock(Content::class));
+        $serviceMock->expects($this->once())->method('deleteVersion')->with(...$parameters);
 
         $decoratedService->deleteVersion(...$parameters);
     }
@@ -371,7 +376,7 @@ public function testDeleteRelationDecorator()
             $this->createMock(ContentInfo::class),
         ];
 
-        $serviceMock->expects($this->once())->method('deleteRelation')->with(...$parameters)->willReturn($this->createMock(Content::class));
+        $serviceMock->expects($this->once())->method('deleteRelation')->with(...$parameters);
 
         $decoratedService->deleteRelation(...$parameters);
     }
@@ -383,10 +388,10 @@ public function testRemoveTranslationDecorator()
 
         $parameters = [
             $this->createMock(ContentInfo::class),
-            'random_value_5ced05ce156ca0.26332407',
+            self::EXAMPLE_LANGUAGE_CODE,
         ];
 
-        $serviceMock->expects($this->once())->method('removeTranslation')->with(...$parameters)->willReturn($this->createMock(Content::class));
+        $serviceMock->expects($this->once())->method('removeTranslation')->with(...$parameters);
 
         $decoratedService->removeTranslation(...$parameters);
     }
@@ -398,10 +403,10 @@ public function testDeleteTranslationDecorator()
 
         $parameters = [
             $this->createMock(ContentInfo::class),
-            'random_value_5ced05ce156d02.84155908',
+            self::EXAMPLE_LANGUAGE_CODE,
         ];
 
-        $serviceMock->expects($this->once())->method('deleteTranslation')->with(...$parameters)->willReturn($this->createMock(Content::class));
+        $serviceMock->expects($this->once())->method('deleteTranslation')->with(...$parameters);
 
         $decoratedService->deleteTranslation(...$parameters);
     }