Enable contributesAsInject by default

CHANGELOG.md

@@ -28,12 +28,19 @@ Changelog
 
 - [IR] Never eagerly init graph extension impls (scoped or not).
 - [IR] Don't cache creator-less scoped graph extension impls in their parent graphs. This was initially implemented this way due to a misunderstanding to how Dagger generated subcomponents! Getters for graph extensions now always return new instances.
+- [IR] Check for `open` or `final` modality on classes first before searching for injectable constructors.
 - [IC] Record lookups of contributed classes when looking up hints from IR. Previously Metro only recorded a lookup of the generated hint function, which appears to not be enough for Kotlin 2.3.20.
 - [IC] Link IR-generated hint function files back to source class via expect-actual tracker to link their compilations. This fixes an edge case where simply changing a contribution scope (or removing it) could leave behind a stale hint file that downstream compilations would incidentally read.
 - [FIR] Ensure hint functions generated by FIR hint generation match the visibility of the source contributor.
 
 ### Changes
 
+- Enable `contributesAsInject` by default. See its docs for more details, but in short this means that `@Inject` is now optional on `@ContributesBinding`, `@ContributesIntoSet`, and `@ContributesIntoMap` annotated declarations.
+  ```kotlin
+  @ContributesBinding(AppScope::class)
+  // @Inject // <-- now implicit!
+  class TacoImpl(...) : Taco
+  ```
 - [IR] Already mentioned above, but worth calling out again — creator-less scoped graph extensions _are no longer cached_ in their parent graphs. Accessors to this will always get new instances now.
 - [IR] Report log files reported from within graph generation now use snake-cased fully-qualified names of the impl graph as the file name suffix.
 - [IR] Do not report similar bindings when a missing binding has type `kotlin.Any`. In practice this reported all available bindings.

compiler/src/main/kotlin/dev/zacsweers/metro/compiler/ir/ir.kt

@@ -37,6 +37,7 @@ import org.jetbrains.kotlin.backend.jvm.ir.isWithFlexibleNullability
 import org.jetbrains.kotlin.builtins.StandardNames
 import org.jetbrains.kotlin.cli.common.messages.CompilerMessageLocationWithRange
 import org.jetbrains.kotlin.cli.common.messages.CompilerMessageSourceLocation
+import org.jetbrains.kotlin.descriptors.ClassKind
 import org.jetbrains.kotlin.descriptors.DescriptorVisibilities
 import org.jetbrains.kotlin.descriptors.DescriptorVisibility
 import org.jetbrains.kotlin.descriptors.Modality
@@ -1551,9 +1552,11 @@ private fun List<IrConstructorCall>?.annotationsAnnotatedWith(
 
 context(context: IrMetroContext)
 internal fun IrClass.findInjectableConstructor(onlyUsePrimaryConstructor: Boolean): IrConstructor? {
-  if (kind.isObject) {
+  if (kind != ClassKind.CLASS) {
     // No constructor for this one but can be annotated with Contributes*
     return null
+  } else if (modality != Modality.FINAL && modality != Modality.OPEN) {
+    return null
   }
   return findInjectableConstructor(
     onlyUsePrimaryConstructor,

gradle-plugin/src/main/kotlin/dev/zacsweers/metro/gradle/MetroPluginExtension.kt

@@ -251,10 +251,10 @@ constructor(
    * If enabled, treats `@Contributes*` annotations (except ContributesTo) as implicit `@Inject`
    * annotations.
    *
-   * Disabled by default.
+   * Enabled by default.
    */
   public val contributesAsInject: Property<Boolean> =
-    objects.property(Boolean::class.javaObjectType).convention(false)
+    objects.property(Boolean::class.javaObjectType).convention(true)
 
   /**
    * If set, the Metro compiler will dump verbose report diagnostics about resolved dependency