Add the unit tests.

src/Controller/BackendController.php

@@ -225,7 +225,6 @@ public function alertsAction()
      *
      * @return RedirectResponse
      *
-     *
      * @Route("/_contao/picker", name="contao_backend_picker")
      */
     public function pickerAction(Request $request)

src/Picker/AbstractPickerProvider.php

@@ -105,8 +105,8 @@ protected function getUser()
 
         $user = $token->getUser();
 
-        if (null === $user) {
-            throw new \RuntimeException('The token does not contain a user');
+        if (!($user instanceof BackendUser)) {
+            throw new \RuntimeException('The token does not contain a back end user object');
         }
 
         return $user;

src/Picker/ArticlePickerProvider.php

@@ -56,7 +56,7 @@ public function getDcaAttributes(PickerConfig $config)
     {
         $attributes = ['fieldType' => 'radio'];
 
-        if ('link' === $config->getContext() && $this->supportsValue($config)) {
+        if ($this->supportsValue($config)) {
             $attributes['value'] = str_replace(['{{article_url::', '}}'], '', $config->getValue());
         }
 

src/Picker/FilePickerProvider.php

@@ -65,19 +65,13 @@ public function supportsContext($context)
      */
     public function supportsValue(PickerConfig $config)
     {
-        if ('link' === $config->getContext()
-            && (false !== strpos($config->getValue(), '{{file::')
-                || 0 === strpos($config->getValue(), $this->uploadPath)
-            )
-        ) {
-            return true;
-        }
-
-        if ('file' === $config->getContext() && Validator::isUuid($config->getValue())) {
-            return true;
+        if ('file' === $config->getContext()) {
+            return Validator::isUuid($config->getValue());
         }
 
-        return false;
+        return false !== strpos($config->getValue(), '{{file::')
+            || 0 === strpos($config->getValue(), $this->uploadPath)
+        ;
     }
 
     /**
@@ -93,11 +87,10 @@ public function getDcaTable()
      */
     public function getDcaAttributes(PickerConfig $config)
     {
-        $attributes = [];
         $value = $config->getValue();
 
         if ('file' === $config->getContext()) {
-            $attributes += array_intersect_key(
+            $attributes = array_intersect_key(
                 $config->getExtras(),
                 array_flip(['fieldType', 'files', 'filesOnly', 'path', 'extensions'])
             );
@@ -109,20 +102,24 @@ public function getDcaAttributes(PickerConfig $config)
                     $attributes['value'][] = $this->urlEncode($this->convertValueToPath($v));
                 }
             }
-        } elseif ('link' === $config->getContext()) {
-            $attributes['fieldType'] = 'radio';
-            $attributes['filesOnly'] = true;
 
-            if ($value) {
-                if (false !== strpos($value, '{{file::')) {
-                    $value = str_replace(['{{file::', '}}'], '', $value);
-                }
+            return $attributes;
+        }
 
-                if (0 === strpos($value, $this->uploadPath.'/')) {
-                    $attributes['value'] = $this->urlEncode($value);
-                } else {
-                    $attributes['value'] = $this->urlEncode($this->convertValueToPath($value));
-                }
+        $attributes = [
+            'fieldType' => 'radio',
+            'filesOnly' => true,
+        ];
+
+        if ($value) {
+            if (false !== strpos($value, '{{file::')) {
+                $value = str_replace(['{{file::', '}}'], '', $value);
+            }
+
+            if (0 === strpos($value, $this->uploadPath.'/')) {
+                $attributes['value'] = $this->urlEncode($value);
+            } else {
+                $attributes['value'] = $this->urlEncode($this->convertValueToPath($value));
             }
         }
 
@@ -134,14 +131,13 @@ public function getDcaAttributes(PickerConfig $config)
      */
     public function convertDcaValue(PickerConfig $config, $value)
     {
-        if ('link' === $config->getContext()) {
-            /** @var FilesModel $filesModel */
-            $filesModel = $this->framework->getAdapter(FilesModel::class);
-            $file = $filesModel->findByPath(rawurldecode($value));
+        /** @var FilesModel $filesAdapter */
+        $filesAdapter = $this->framework->getAdapter(FilesModel::class);
 
-            if (null !== $file) {
-                return '{{file::'.StringUtil::binToUuid($file->uuid).'}}';
-            }
+        $filesModel = $filesAdapter->findByPath(rawurldecode($value));
+
+        if ($filesModel instanceof FilesModel) {
+            return '{{file::'.StringUtil::binToUuid($filesModel->uuid).'}}';
         }
 
         return $value;
@@ -172,11 +168,11 @@ protected function getRouteParameters(PickerConfig $config)
      */
     private function convertValueToPath($value)
     {
-        /** @var FilesModel $filesModel */
-        $filesModel = $this->framework->getAdapter(FilesModel::class);
+        /** @var FilesModel $filesAdapter */
+        $filesAdapter = $this->framework->getAdapter(FilesModel::class);
 
-        if (Validator::isUuid($value) && ($file = $filesModel->findByUuid($value)) instanceof FilesModel) {
-            return $file->path;
+        if (Validator::isUuid($value) && ($filesModel = $filesAdapter->findByUuid($value)) instanceof FilesModel) {
+            return $filesModel->path;
         }
 
         return $value;

src/Picker/PagePickerProvider.php

@@ -38,15 +38,11 @@ public function supportsContext($context)
      */
     public function supportsValue(PickerConfig $config)
     {
-        if ('link' === $config->getContext() && false !== strpos($config->getValue(), '{{link_url::')) {
-            return true;
-        }
-
-        if ('page' === $config->getContext() && is_numeric($config->getValue())) {
-            return true;
+        if ('page' === $config->getContext()) {
+            return is_numeric($config->getValue());
         }
 
-        return false;
+        return false !== strpos($config->getValue(), '{{link_url::');
     }
 
     /**
@@ -62,7 +58,6 @@ public function getDcaTable()
      */
     public function getDcaAttributes(PickerConfig $config)
     {
-        $attributes = [];
         $value = $config->getValue();
 
         if ('page' === $config->getContext()) {
@@ -75,12 +70,14 @@ public function getDcaAttributes(PickerConfig $config)
             if ($value) {
                 $attributes['value'] = array_map('intval', explode(',', $value));
             }
-        } elseif ('link' === $config->getContext()) {
-            $attributes = ['fieldType' => 'radio'];
 
-            if ($value && false !== strpos($value, '{{link_url::')) {
-                $attributes['value'] = str_replace(['{{link_url::', '}}'], '', $value);
-            }
+            return $attributes;
+        }
+
+        $attributes = ['fieldType' => 'radio'];
+
+        if ($value && false !== strpos($value, '{{link_url::')) {
+            $attributes['value'] = str_replace(['{{link_url::', '}}'], '', $value);
         }
 
         return $attributes;
@@ -91,11 +88,11 @@ public function getDcaAttributes(PickerConfig $config)
      */
     public function convertDcaValue(PickerConfig $config, $value)
     {
-        if ('link' === $config->getContext()) {
-            return '{{link_url::'.$value.'}}';
+        if ('page' === $config->getContext()) {
+            return (int) $value;
         }
 
-        return (int) $value;
+        return '{{link_url::'.$value.'}}';
     }
 
     /**

src/Picker/Picker.php

@@ -108,7 +108,7 @@ public function getCurrentUrl()
             throw new \RuntimeException('No picker menu items found.');
         }
 
-        /** @var ItemInterface $menu */
+        /** @var ItemInterface[] $menu */
         foreach ($menu as $item) {
             $picker = $item->getExtra('provider');
 

src/Picker/PickerConfig.php

@@ -63,6 +63,16 @@ public function getContext()
         return $this->context;
     }
 
+    /**
+     * Returns the extras.
+     *
+     * @return array
+     */
+    public function getExtras()
+    {
+        return $this->extras;
+    }
+
     /**
      * Returns the value.
      *
@@ -83,16 +93,6 @@ public function getCurrent()
         return $this->current;
     }
 
-    /**
-     * Returns the extras.
-     *
-     * @return array
-     */
-    public function getExtras()
-    {
-        return $this->extras;
-    }
-
     /**
      * Returns an extra by name.
      *
@@ -135,24 +135,22 @@ public function jsonSerialize()
     {
         return [
             'context' => $this->context,
+            'extras' => $this->extras,
             'current' => $this->current,
             'value' => $this->value,
-            'extras' => $this->extras,
         ];
     }
 
     /**
      * Encodes the picker configuration for the URL.
      *
-     * @param bool $compress
-     *
      * @return string
      */
-    public function urlEncode($compress = true)
+    public function urlEncode()
     {
         $data = json_encode($this);
 
-        if ($compress && function_exists('gzencode') && false !== ($encoded = @gzencode($data))) {
+        if (function_exists('gzencode') && false !== ($encoded = @gzencode($data))) {
             $data = $encoded;
         }