[ObjCExport] Add object translation and error handling

- Also add forward declaration tests
- Add hidden types support
- Issues: KT-64857, KT-64952, KT-65080

native/objcexport-header-generator/test/org/jetbrains/kotlin/backend/konan/testUtils/HeaderGenerator.kt

@@ -0,0 +1,18 @@
+/*
+ * Copyright 2010-2024 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
+ */
+
+package org.jetbrains.kotlin.backend.konan.testUtils
+
+import org.jetbrains.kotlin.backend.konan.objcexport.ObjCHeader
+import java.io.File
+
+interface HeaderGenerator {
+
+    data class Configuration(
+        val frameworkName: String = "",
+    )
+
+    fun generateHeaders(root: File, configuration: Configuration = Configuration()): ObjCHeader
+}

native/objcexport-header-generator/test/org/jetbrains/kotlin/backend/konan/testUtils/testDataDir.kt

@@ -9,4 +9,5 @@ import java.io.File
 
 val testDataDir = File("native/objcexport-header-generator/testData")
 val headersTestDataDir = testDataDir.resolve("headers")
-val baseDeclarationsDir = testDataDir.resolve("baseDeclarations")
+val baseDeclarationsDir = testDataDir.resolve("baseDeclarations")
+val forwardDeclarationsDir = testDataDir.resolve("forwardDeclarations")

native/objcexport-header-generator/test/org/jetbrains/kotlin/backend/konan/tests/ObjCExportForwardDeclarationsTest.kt

@@ -0,0 +1,48 @@
+/*
+ * Copyright 2010-2024 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
+ */
+
+package org.jetbrains.kotlin.backend.konan.tests
+
+import org.jetbrains.kotlin.backend.konan.testUtils.HeaderGenerator
+import org.jetbrains.kotlin.backend.konan.testUtils.forwardDeclarationsDir
+import org.jetbrains.kotlin.test.KotlinTestUtils
+import org.junit.jupiter.api.Test
+import java.io.File
+import kotlin.test.fail
+
+class ObjCExportForwardDeclarationsTest(
+    private val generator: HeaderGenerator,
+) {
+
+    @Test
+    fun `test - function returning interface`() {
+        doTest(forwardDeclarationsDir.resolve("functionReturningInterface"))
+    }
+
+    @Test
+    fun `test - function returning class`() {
+        doTest(forwardDeclarationsDir.resolve("functionReturningClass"))
+    }
+
+    @Test
+    fun `test - property returning interface`() {
+        doTest(forwardDeclarationsDir.resolve("propertyReturningInterface"))
+    }
+
+    @Test
+    fun `test - property returning class`() {
+        doTest(forwardDeclarationsDir.resolve("propertyReturningClass"))
+    }
+
+    private fun doTest(root: File) {
+        if (!root.isDirectory) fail("Expected ${root.absolutePath} to be directory")
+        val generatedHeaders = generator.generateHeaders(root)
+        val renderedForwardDeclarations = buildString {
+            generatedHeaders.renderClassForwardDeclarations().forEach(this::appendLine)
+            generatedHeaders.renderProtocolForwardDeclarations().forEach(this::appendLine)
+        }
+        KotlinTestUtils.assertEqualsToFile(root.resolve("!${root.nameWithoutExtension}.h"), renderedForwardDeclarations)
+    }
+}

native/objcexport-header-generator/test/org/jetbrains/kotlin/backend/konan/tests/ObjCExportHeaderGeneratorTest.kt

@@ -5,6 +5,8 @@
 
 package org.jetbrains.kotlin.backend.konan.tests
 
+import org.jetbrains.kotlin.backend.konan.testUtils.HeaderGenerator
+import org.jetbrains.kotlin.backend.konan.testUtils.HeaderGenerator.Configuration
 import org.jetbrains.kotlin.backend.konan.testUtils.headersTestDataDir
 import org.jetbrains.kotlin.test.KotlinTestUtils
 import org.junit.jupiter.api.Test
@@ -110,6 +112,11 @@ class ObjCExportHeaderGeneratorTest(val generator: HeaderGenerator) {
         doTest(headersTestDataDir.resolve("functionWithErrorType"))
     }
 
+    @Test
+    fun `test - functionWithErrorTypeAndFrameworkName`() {
+        doTest(headersTestDataDir.resolve("functionWithErrorTypeAndFrameworkName"), Configuration(frameworkName = "shared"))
+    }
+
     @Test
     fun `test - kdocWithBlockTags`() {
         doTest(headersTestDataDir.resolve("kdocWithBlockTags"))
@@ -145,13 +152,19 @@ class ObjCExportHeaderGeneratorTest(val generator: HeaderGenerator) {
         doTest(headersTestDataDir.resolve("dispatchAndExtensionReceiverWithMustBeDocumentedAnnotation"))
     }
 
-    fun interface HeaderGenerator {
-        fun generateHeaders(root: File): String
+    @Test
+    fun `test - classWithUnresolvedSuperType`() {
+        doTest(headersTestDataDir.resolve("classWithUnresolvedSuperType"))
     }
 
-    private fun doTest(root: File) {
+    @Test
+    fun `test - classWithUnresolvedSuperTypeGenerics`() {
+        doTest(headersTestDataDir.resolve("classWithUnresolvedSuperTypeGenerics"))
+    }
+
+    private fun doTest(root: File, configuration: Configuration = Configuration()) {
         if (!root.isDirectory) fail("Expected ${root.absolutePath} to be directory")
-        val generatedHeaders = generator.generateHeaders(root)
+        val generatedHeaders = generator.generateHeaders(root, configuration).toString()
         KotlinTestUtils.assertEqualsToFile(root.resolve("!${root.nameWithoutExtension}.h"), generatedHeaders)
     }
 }