[ObjCExport] Extract header generation to shared module

^KT-64227 Fixed

native/objcexport-header-generator/impl/k1/src/org/jetbrains/kotlin/backend/konan/objcexport/ObjCExportHeaderGenerator.kt

@@ -1151,61 +1151,13 @@ abstract class ObjCExportHeaderGenerator @InternalKotlinNativeApi constructor(
 
     open val shouldExportKDoc = false
 
-    fun build(): List<String> = mutableListOf<String>().apply {
+    fun build(): List<String> = ObjCHeader(
-        addImports(foundationImports)
+        stubs = stubs,
-        addImports(getAdditionalImports())
+        classForwardDeclarations = classForwardDeclarations,
-        add("")
+        protocolForwardDeclarations = protocolForwardDeclarations,
-
+        additionalImports = getAdditionalImports(),
-        if (classForwardDeclarations.isNotEmpty()) {
+        exportKDoc = shouldExportKDoc
-            add("@class ${
+    ).lines
-                classForwardDeclarations.joinToString {
-                    buildString {
-                        append(it.className)
-                        formatGenerics(this, it.typeDeclarations)
-                    }
-                }
-            };")
-            add("")
-        }
-
-        if (protocolForwardDeclarations.isNotEmpty()) {
-            add("@protocol ${protocolForwardDeclarations.joinToString()};")
-            add("")
-        }
-
-        add("NS_ASSUME_NONNULL_BEGIN")
-        add("#pragma clang diagnostic push")
-        listOf(
-            "-Wunknown-warning-option",
-
-            // Protocols don't have generics, classes do. So generated header may contain
-            // overriding property with "incompatible" type, e.g. `Generic<T>`-typed property
-            // overriding `Generic<id>`. Suppress these warnings:
-            "-Wincompatible-property-type",
-
-            "-Wnullability"
-        ).forEach {
-            add("#pragma clang diagnostic ignored \"$it\"")
-        }
-        add("")
-
-        // If _Nullable_result is not supported, then use _Nullable:
-        add("#pragma push_macro(\"$objcNullableResultAttribute\")")
-        add("#if !__has_feature(nullability_nullable_result)")
-        add("#undef $objcNullableResultAttribute")
-        add("#define $objcNullableResultAttribute $objcNullableAttribute")
-        add("#endif")
-        add("")
-
-        stubs.forEach {
-            addAll(StubRenderer.render(it, shouldExportKDoc))
-            add("")
-        }
-
-        add("#pragma pop_macro(\"$objcNullableResultAttribute\")")
-        add("#pragma clang diagnostic pop")
-        add("NS_ASSUME_NONNULL_END")
-    }
 
     @InternalKotlinNativeApi
     fun buildInterface(): ObjCExportedInterface {

native/objcexport-header-generator/src/org/jetbrains/kotlin/backend/konan/objcexport/ObjCHeader.kt

@@ -0,0 +1,90 @@
+/*
+ * Copyright 2010-2023 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.objcexport
+
+data class ObjCHeader(val lines: List<String>) {
+    override fun toString(): String {
+        return lines.joinToString(System.lineSeparator())
+    }
+}
+
+fun ObjCHeader(
+    stubs: List<ObjCExportStub>,
+    classForwardDeclarations: Set<ObjCClassForwardDeclaration>,
+    protocolForwardDeclarations: Set<String>,
+    additionalImports: List<String> = emptyList(),
+    exportKDoc: Boolean = false,
+): ObjCHeader = ObjCHeader(buildList {
+    addImports(foundationImports)
+    addImports(additionalImports)
+    add("")
+
+    if (classForwardDeclarations.isNotEmpty()) {
+        add("@class ${
+            classForwardDeclarations.joinToString {
+                buildString {
+                    append(it.className)
+                    formatGenerics(this, it.typeDeclarations)
+                }
+            }
+        };")
+        add("")
+    }
+
+    if (protocolForwardDeclarations.isNotEmpty()) {
+        add("@protocol ${protocolForwardDeclarations.joinToString()};")
+        add("")
+    }
+
+    add("NS_ASSUME_NONNULL_BEGIN")
+    add("#pragma clang diagnostic push")
+    listOf(
+        "-Wunknown-warning-option",
+
+        // Protocols don't have generics, classes do. So generated header may contain
+        // overriding property with "incompatible" type, e.g. `Generic<T>`-typed property
+        // overriding `Generic<id>`. Suppress these warnings:
+        "-Wincompatible-property-type",
+
+        "-Wnullability"
+    ).forEach {
+        add("#pragma clang diagnostic ignored \"$it\"")
+    }
+    add("")
+
+    // If _Nullable_result is not supported, then use _Nullable:
+    add("#pragma push_macro(\"$objcNullableResultAttribute\")")
+    add("#if !__has_feature(nullability_nullable_result)")
+    add("#undef $objcNullableResultAttribute")
+    add("#define $objcNullableResultAttribute $objcNullableAttribute")
+    add("#endif")
+    add("")
+
+    stubs.forEach {
+        addAll(StubRenderer.render(it, exportKDoc))
+        add("")
+    }
+
+    add("#pragma pop_macro(\"$objcNullableResultAttribute\")")
+    add("#pragma clang diagnostic pop")
+    add("NS_ASSUME_NONNULL_END")
+})
+
+private fun MutableList<String>.addImports(imports: Iterable<String>) {
+    imports.forEach {
+        add("#import <$it>")
+    }
+}
+
+private val foundationImports = listOf(
+    "Foundation/NSArray.h",
+    "Foundation/NSDictionary.h",
+    "Foundation/NSError.h",
+    "Foundation/NSObject.h",
+    "Foundation/NSSet.h",
+    "Foundation/NSString.h",
+    "Foundation/NSValue.h"
+)