File associations

gradle-plugins/compose/src/main/kotlin/org/jetbrains/compose/desktop/application/dsl/JvmApplicationDistributions.kt

@@ -34,12 +34,13 @@ abstract class JvmApplicationDistributions : AbstractDistributions() {
         fn.execute(windows)
     }
 
+    @JvmOverloads
     fun fileAssociation(
         mimeType: String, extension: String, description: String,
-        linuxIcon: File? = null, windowsIcon: File? = null, macOSIcon: File? = null,
+        linuxIconFile: File? = null, windowsIconFile: File? = null, macOSIconFile: File? = null,
     ) {
-        linux.fileAssociation(mimeType, extension, description, linuxIcon)
-        windows.fileAssociation(mimeType, extension, description, windowsIcon)
-        macOS.fileAssociation(mimeType, extension, description, macOSIcon)
+        linux.fileAssociation(mimeType, extension, description, linuxIconFile)
+        windows.fileAssociation(mimeType, extension, description, windowsIconFile)
+        macOS.fileAssociation(mimeType, extension, description, macOSIconFile)
     }
 }

gradle-plugins/compose/src/main/kotlin/org/jetbrains/compose/desktop/application/dsl/PlatformSettings.kt

@@ -20,6 +20,8 @@ abstract class AbstractPlatformSettings {
     var installationPath: String? = null
 
     internal val fileAssociations: MutableSet<FileAssociation> = mutableSetOf()
+
+    @JvmOverloads
     fun fileAssociation(mimeType: String, extension: String, description: String, iconFile: File? = null) {
         fileAssociations.add(FileAssociation(mimeType, extension, description, iconFile))
     }

gradle-plugins/compose/src/main/kotlin/org/jetbrains/compose/desktop/application/tasks/AbstractJPackageTask.kt

@@ -253,19 +253,33 @@ abstract class AbstractJPackageTask @Inject constructor(
     internal val fileAssociations: SetProperty<FileAssociation> = objects.setProperty(FileAssociation::class.java)
 
     private val iconMapping by lazy {
-        val icons = fileAssociations.orNull.orEmpty().mapNotNull { it.iconFile }
+        val icons = fileAssociations.orNull.orEmpty().mapNotNull { it.iconFile }.distinct()
         if (icons.isEmpty()) return@lazy emptyMap()
-        val iconTempNames = generateSequence {
-            icons.mapTo(mutableSetOf()) { String(CharArray(10) { ('a'..'z').random() }) }
-        }.first { it.size == icons.size }
+        val iconTempNames: List<String> = mutableListOf<String>().apply {
+            val usedNames = mutableSetOf("${packageName.get()}.icns")
+            for (icon in icons) {
+                if (!icon.exists()) continue
+                if (usedNames.add(icon.name)) {
+                    add(icon.name)
+                    continue
+                }
+                val nameWithoutExtension = icon.nameWithoutExtension
+                val extension = icon.extension
+                for (n in 1UL..ULong.MAX_VALUE) {
+                    val newName = "$nameWithoutExtension ($n).$extension"
+                    if (usedNames.add(newName)) {
+                        add(newName)
+                        break
+                    }
+                }
+            }
+        }
         val appDir = destinationDir.ioFile.resolve("${packageName.get()}.app")
         val iconsDir = appDir.resolve("Contents").resolve("Resources")
         if (iconsDir.exists()) {
             iconsDir.deleteRecursively()
         }
-        icons.zip(iconTempNames) { icon, newName ->
-            icon to iconsDir.resolve(newName + icon.name.drop(icon.nameWithoutExtension.length))
-        }.toMap()
+        icons.zip(iconTempNames) { icon, newName -> icon to iconsDir.resolve(newName) }.toMap()
     }
 
     private lateinit var jvmRuntimeInfo: JvmRuntimeProperties

gradle-plugins/compose/src/test/test-projects/application/macOptions/Expected-Info.plist

@@ -32,12 +32,87 @@
     <string>true</string>
     <key>NSHighResolutionCapable</key>
     <string>true</string>
+    <key>CFBundleDocumentTypes</key>
+    <array>
+      <dict>
+        <key>CFBundleTypeRole</key>
+        <string>Editor</string>
+        <key>CFBundleTypeExtensions</key>
+        <array>
+          <string>kot</string>
+        </array>
+        <key>CFBundleTypeIconFile</key>
+        <string>Kotlin_icon_big.icns</string>
+        <key>CFBundleTypeMIMETypes</key>
+        <string>text/kotlin</string>
+        <key>CFBundleTypeName</key>
+        <string>Kotlin Source File0</string>
+        <key>CFBundleTypeOSTypes</key>
+        <array>
+          <string>****</string>
+        </array>
+      </dict>
+      <dict>
+        <key>CFBundleTypeRole</key>
+        <string>Editor</string>
+        <key>CFBundleTypeExtensions</key>
+        <array>
+          <string>kot1</string>
+        </array>
+        <key>CFBundleTypeIconFile</key>
+        <string>TestPackage.icns</string>
+        <key>CFBundleTypeMIMETypes</key>
+        <string>text/kotlin</string>
+        <key>CFBundleTypeName</key>
+        <string>Kotlin Source File1</string>
+        <key>CFBundleTypeOSTypes</key>
+        <array>
+          <string>****</string>
+        </array>
+      </dict>
+      <dict>
+        <key>CFBundleTypeRole</key>
+        <string>Editor</string>
+        <key>CFBundleTypeExtensions</key>
+        <array>
+          <string>kott</string>
+        </array>
+        <key>CFBundleTypeIconFile</key>
+        <string>Kotlin_icon_big (1).icns</string>
+        <key>CFBundleTypeMIMETypes</key>
+        <string>text/kotlin</string>
+        <key>CFBundleTypeName</key>
+        <string>Kotlin Source File2</string>
+        <key>CFBundleTypeOSTypes</key>
+        <array>
+          <string>****</string>
+        </array>
+      </dict>
+      <dict>
+        <key>CFBundleTypeRole</key>
+        <string>Editor</string>
+        <key>CFBundleTypeExtensions</key>
+        <array>
+          <string>kott1</string>
+        </array>
+        <key>CFBundleTypeIconFile</key>
+        <string>TestPackage.icns</string>
+        <key>CFBundleTypeMIMETypes</key>
+        <string>text/kotlin</string>
+        <key>CFBundleTypeName</key>
+        <string>Kotlin Source File3</string>
+        <key>CFBundleTypeOSTypes</key>
+        <array>
+          <string>****</string>
+        </array>
+      </dict>
+    </array>
 
     <key>CFBundleURLTypes</key>
     <array>
       <dict>
         <key>CFBundleURLName</key>
-        <string>Exameple URL</string>
+        <string>Example URL</string>
         <key>CFBundleURLSchemes</key>
         <array>
           <string>exampleUrl</string>

gradle-plugins/compose/src/test/test-projects/application/macOptions/build.gradle

@@ -15,7 +15,7 @@ def extraInfoPlistKeys = """
     <array>
       <dict>
         <key>CFBundleURLName</key>
-        <string>Exameple URL</string>
+        <string>Example URL</string>
         <key>CFBundleURLSchemes</key>
         <array>
           <string>exampleUrl</string>
@@ -28,12 +28,36 @@ compose.desktop {
         mainClass = "MainKt"
         nativeDistributions {
             packageName = "TestPackage"
+            fileAssociation(
+                    "text/kotlin",
+                    "kot",
+                    "Kotlin Source File0",
+                    project.file("Kotlin_icon_big.png"),
+                    project.file("Kotlin_icon_big.ico"),
+                    project.file("Kotlin_icon_big.icns"),
+            )
+            fileAssociation(
+                    "text/kotlin",
+                    "kot1",
+                    "Kotlin Source File1",
+            )
             macOS {
                 dockName = "CustomDockName"
                 minimumSystemVersion = "12.0"
                 infoPlist {
                     extraKeysRawXml = extraInfoPlistKeys
                 }
+                fileAssociation(
+                    "text/kotlin",
+                    "kott",
+                    "Kotlin Source File2",
+                    project.file("subdir/Kotlin_icon_big.icns"),
+                )
+                fileAssociation(
+                    "text/kotlin",
+                    "kott1",
+                    "Kotlin Source File3",
+                )
             }
         }
     }

tutorials/Native_distributions_and_local_execution/README.md

@@ -511,6 +511,60 @@ compose.desktop {
 }
 ```
 
+## File associations
+
+File associations can be added with `fileAssociation` function.
+These associations can optionally include custom icons.
+Similar to [app icon](#app-icon), these custom icons also have OS-specific formats: `.icns` for macOS, `.ico` for Windows and `.png` for Linux.
+
+It is possible to specify both OS-specific and OS-agnostic file associations.
+For OS-agnostic you can specify icon files for all three OSes in-place,
+while for OS-specific there is a shorthand with a single icon file parameter.
+
+```kotlin
+compose.desktop {
+    application {
+        mainClass = "MainKt"
+
+        nativeDistributions {
+            targetFormats(TargetFormat.Dmg, TargetFormat.Msi, TargetFormat.Deb)
+
+            packageName = "file-associations-demo"
+            packageVersion = "1.0.0"
+
+            macOS {
+                fileAssociation(
+                    mimeType = "text/kotlin",
+                    extension = "kott",
+                    description = "Kotlin Source File",
+                    iconFile = project.file("Kotlin_icon_big.icns"),
+                )
+                fileAssociation(
+                    mimeType = "text/kotlin",
+                    extension = "ko",
+                    description = "Kotlin Source File",
+                )
+            }
+
+            fileAssociation(
+                mimeType = "text/kotlin",
+                extension = "kot",
+                description = "Kotlin Source File",
+                macOSIconFile = project.file("Kotlin_icon_big.icns"),
+                windowsIconFile = project.file("Kotlin_icon_big.ico"),
+                linuxIconFile = project.file("Kotlin_icon_big.png"),
+            )
+
+            fileAssociation(
+                mimeType = "text/kotlin",
+                extension = "kottt",
+                description = "Kotlin Source File",
+            )
+        }
+    }
+}
+```
+
 ## Customizing Info.plist on macOS
 
 We aim to support important platform-specific customization use-cases via declarative DSL.