Support direct graph extension accessors (#920)

Author: ZacSweers

CHANGELOG.md

@@ -75,10 +75,10 @@ interface LoggedInGraph {
 interface AppGraph : LoggedInGraph.Factory
 ```
 
-- Contribute the factory to the parent graph via ContributesGraphExtension.
+- Contribute the factory to the parent graph via `@ContributesGraphExtension`.
 
 ```kotlin
-@GraphExtension
+@ContributesGraphExtension(LoggedInScope::class)
 interface LoggedInGraph {
   @ContributesGraphExtension.Factory(AppScope::class)
   interface Factory {

compiler-tests/src/test/data/box/dependencygraph/extensions/ExtensionsCanBeDeclaredWithoutFactories.kt

@@ -0,0 +1,20 @@
+@GraphExtension
+interface LoggedInGraph {
+  val int: Int
+}
+
+@DependencyGraph
+interface AppGraph {
+  @Provides fun provideInt(): Int = 3
+
+  fun loggedInGraph(): LoggedInGraph
+
+  val loggedInGraphProp: LoggedInGraph
+}
+
+fun box(): String {
+  val graph = createGraph<AppGraph>()
+  assertEquals(3, graph.loggedInGraph().int)
+  assertEquals(3, graph.loggedInGraphProp.int)
+  return "OK"
+}

compiler-tests/src/test/data/box/dependencygraph/extensions/ScopedExtensionsWithoutFactoriesShouldBeCached.kt

@@ -0,0 +1,24 @@
+abstract class LoggedInScope
+
+@GraphExtension
+@SingleIn(LoggedInScope::class)
+interface LoggedInGraph {
+  val int: Int
+}
+
+@DependencyGraph
+interface AppGraph {
+  @Provides fun provideInt(): Int = 3
+
+  fun loggedInGraph(): LoggedInGraph
+  val loggedInGraphProp: LoggedInGraph
+}
+
+fun box(): String {
+  val graph = createGraph<AppGraph>()
+  val loggedInGraph = graph.loggedInGraph()
+  assertEquals(3, loggedInGraph.int)
+  assertSame(loggedInGraph, graph.loggedInGraph())
+  assertSame(graph.loggedInGraphProp, graph.loggedInGraph())
+  return "OK"
+}

compiler-tests/src/test/data/diagnostic/dependencygraph/extensions/ExtensionAccessorsCannotHaveParameters.fir.diag.txt

@@ -0,0 +1,9 @@
+/ExtensionAccessorsCannotHaveParameters.kt:(294,300): error: Graph extension accessors may not have parameters. Use `@GraphExtension.Factory` instead.
+
+/ExtensionAccessorsCannotHaveParameters.kt:(308,314): error: Graph extension accessors may not have parameters. Use `@GraphExtension.Factory` instead.
+
+/ExtensionAccessorsCannotHaveParameters.kt:(343,349): error: Graph extension accessors may not have extension receivers. Use `@GraphExtension.Factory` instead.
+
+/ExtensionAccessorsCannotHaveParameters.kt:(391,408): error: The feature "context parameters" is experimental and should be enabled explicitly. This can be done by supplying the compiler argument '-Xcontext-parameters', but note that no stability guarantees are provided.
+
+/ExtensionAccessorsCannotHaveParameters.kt:(399,402): error: Graph extension accessors may not have context parameters.

compiler-tests/src/test/data/diagnostic/dependencygraph/extensions/ExtensionAccessorsCannotHaveParameters.kt

@@ -0,0 +1,21 @@
+// RENDER_DIAGNOSTICS_FULL_TEXT
+@GraphExtension
+interface LoggedInGraph {
+  val int: Int
+}
+
+@DependencyGraph
+interface AppGraph {
+  @Provides fun provideInt(): Int = 3
+
+  // Legal
+  fun loggedInGraphFactory(): LoggedInGraph
+
+  // Illegal
+  fun loggedInGraphFactory(<!DEPENDENCY_GRAPH_ERROR!>param1<!>: Long, <!DEPENDENCY_GRAPH_ERROR!>param2<!>: Int): LoggedInGraph
+
+  fun <!DEPENDENCY_GRAPH_ERROR!>String<!>.loggedInGraphFactory(): LoggedInGraph
+
+  <!UNSUPPORTED_FEATURE!>context(<!DEPENDENCY_GRAPH_ERROR!>int<!>: Int)<!>
+  fun loggedInGraphFactory(): LoggedInGraph
+}

compiler-tests/src/test/data/diagnostic/dependencygraph/extensions/ExtensionsWithFactoriesMustUseThem.fir.diag.txt

@@ -0,0 +1 @@
+/ExtensionsWithFactoriesMustUseThem.kt:(389,402): error: Graph extension 'LoggedInGraph' has a creator type 'LoggedInGraph.Factory' that must be used to create its instances. Either make 'AppGraph' implement 'LoggedInGraph.Factory' or expose an accessor for 'LoggedInGraph.Factory' instead of 'LoggedInGraph' directly.

compiler-tests/src/test/data/diagnostic/dependencygraph/extensions/ExtensionsWithFactoriesMustUseThem.kt

@@ -0,0 +1,23 @@
+// RENDER_DIAGNOSTICS_FULL_TEXT
+@GraphExtension
+interface LoggedInGraph {
+  val int: Int
+
+  @GraphExtension.Factory
+  interface Factory {
+    fun create(): LoggedInGraph
+  }
+}
+
+@DependencyGraph
+interface AppGraph : LoggedInGraph.Factory {
+  @Provides fun provideInt(): Int = 3
+
+  // Illegal even though AppGraph implements _a_ factory, just not this one
+  fun <!DEPENDENCY_GRAPH_ERROR!>loggedInGraph<!>(): LoggedInGraph
+
+  // Legal
+  fun loggedInGraphFactory(): LoggedInGraph.Factory
+
+  override fun create(): LoggedInGraph
+}

compiler-tests/src/test/data/dump/ir/dependencygraph/UnusedScopedConstructorInjectedClassWithConstructorAnnotatedIsDiscovered.fir.kt.txt

@@ -113,7 +113,10 @@ interface ExampleGraph : $$MetroContributionToAppScope {
     class LoggedInGraphImpl : LoggedInGraph {
       private /* final field */ val exampleGraphInstance: $$MetroGraph = $$MetroGraph
       private /* final field */ val exampleGraphInstanceProvider: Provider<$$MetroGraph> = Companion.invoke<$$MetroGraph>(value = $$MetroGraph)
-      private /* final field */ val dependencyProvider: Provider<Dependency> = <this>.#exampleGraphInstance.accessor_kKldZjk_provider()
+      private /* final field */ val dependencyProvider: Provider<Dependency> = provider<Dependency>(provider = local fun <anonymous>(): Dependency {
+        return <this>.#exampleGraphInstance.accessor_kKldZjk_provider().invoke()
+      }
+)
       private /* final field */ val childDependencyProvider: Provider<ChildDependency> = Companion.provider<Provider<ChildDependency>, ChildDependency>(delegate = Companion.create(dep = <this>.#dependencyProvider))
       constructor($$MetroGraph: $$MetroGraph) /* primary */ {
         super/*Any*/()