From 3f3f6eb5a8e6655be24b5f11bde011cd29fe41a2 Mon Sep 17 00:00:00 2001
From: Svyatoslav Scherbina <svyatoslav.scherbina@jetbrains.com>
Date: Thu, 6 Jul 2023 12:59:58 +0200
Subject: [PATCH] Native: add ExperimentalForeignApi to generated cinterop
 declarations

cinterop tool should add ExperimentalForeignApi to all generated
declarations by default. This commit implements adding the annotation.
Nested declarations don't get the annotation, because they inherit the
opt-in requirement from the enclosing classes implicitly.

The annotation is not added to platform libraries, as intended. See
previous commits.

^KT-58362
---
 .../native/interop/gen/StubIrBuilder.kt       | 47 +++++++++++++++++++
 1 file changed, 47 insertions(+)

diff --git a/kotlin-native/Interop/StubGenerator/src/main/kotlin/org/jetbrains/kotlin/native/interop/gen/StubIrBuilder.kt b/kotlin-native/Interop/StubGenerator/src/main/kotlin/org/jetbrains/kotlin/native/interop/gen/StubIrBuilder.kt
index 65cd797a16a..47cf81629f3 100644
--- a/kotlin-native/Interop/StubGenerator/src/main/kotlin/org/jetbrains/kotlin/native/interop/gen/StubIrBuilder.kt
+++ b/kotlin-native/Interop/StubGenerator/src/main/kotlin/org/jetbrains/kotlin/native/interop/gen/StubIrBuilder.kt
@@ -350,6 +350,9 @@ class StubIrBuilder(private val context: StubIrContext) {
                 typealiases.toList(),
                 containers.toList()
         )
+
+        stubs.addExperimentalAnnotations()
+
         return StubIrBuilderResult(
                 stubs,
                 buildingContext.declarationMapper,
@@ -358,6 +361,50 @@ class StubIrBuilder(private val context: StubIrContext) {
         )
     }
 
+    private fun StubContainer.addExperimentalAnnotations() {
+        fun MutableList<AnnotationStub>.addExperimentalIfNecessary() {
+            if (!configuration.disableExperimentalAnnotation)
+                this.add(AnnotationStub.ExperimentalForeignApi)
+        }
+
+        this.accept(object : StubIrVisitor<Unit, Unit> {
+            override fun visitSimpleStubContainer(simpleStubContainer: SimpleStubContainer, data: Unit) {
+                simpleStubContainer.children.forEach { it.accept(this, data) }
+                simpleStubContainer.simpleContainers.forEach { visitSimpleStubContainer(it, data) }
+            }
+
+            override fun visitClass(element: ClassStub, data: Unit) {
+                val annotations = when (element) {
+                    is ClassStub.Companion -> return // Nested, see below.
+                    is ClassStub.Enum -> element.annotations
+                    is ClassStub.Simple -> element.annotations
+                }
+                annotations.addExperimentalIfNecessary()
+                // Not visiting nested declarations intentionally -- they inherit opt-in requirement from the enclosing
+                // class.
+            }
+
+            override fun visitTypealias(element: TypealiasStub, data: Unit) {
+                element.annotations.addExperimentalIfNecessary()
+            }
+
+            override fun visitFunction(element: FunctionStub, data: Unit) {
+                element.annotations.addExperimentalIfNecessary()
+            }
+
+            override fun visitProperty(element: PropertyStub, data: Unit) {
+                element.annotations.addExperimentalIfNecessary()
+            }
+
+            // Not visiting nested declarations intentionally -- they inherit opt-in requirement from the enclosing
+            // class.
+            override fun visitConstructor(constructorStub: ConstructorStub, data: Unit) {}
+
+            // Property accessors inherit opt-in requirements from the property.
+            override fun visitPropertyAccessor(propertyAccessor: PropertyAccessor, data: Unit) {}
+        }, Unit)
+    }
+
     private fun generateStubsForWrappedMacro(macro: WrappedMacroDef) {
         try {
             generateStubsForGlobal(GlobalDecl(macro.name, macro.type, isConst = true))