[J2KT] Implement rendering of J2ObjC-compatible "J2ObjCCompat.h" head…

…er file. PiperOrigin-RevId: 502078848
google · Jan 14, 2023 · 0e13b9a · 0e13b9a
1 parent 97cfb09
commit 0e13b9a
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Showing 6 changed files with 271 additions and 32 deletions.
diff --git a/transpiler/java/com/google/j2cl/transpiler/backend/kotlin/BUILD b/transpiler/java/com/google/j2cl/transpiler/backend/kotlin/BUILD
@@ -17,5 +17,7 @@ kt_jvm_library(
         "//transpiler/java/com/google/j2cl/transpiler/backend/common",
         "//transpiler/java/com/google/j2cl/transpiler/backend/kotlin/ast",
         "//transpiler/java/com/google/j2cl/transpiler/backend/kotlin/common",
+        "//transpiler/java/com/google/j2cl/transpiler/backend/kotlin/objc",
+        "//transpiler/java/com/google/j2cl/transpiler/backend/kotlin/source",
     ],
 )
diff --git a/transpiler/java/com/google/j2cl/transpiler/backend/kotlin/J2ObjCCompat.kt b/transpiler/java/com/google/j2cl/transpiler/backend/kotlin/J2ObjCCompat.kt
@@ -0,0 +1,233 @@
+/*
+ * Copyright 2023 Google Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may not
+ * use this file except in compliance with the License. You may obtain a copy of
+ * the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations under
+ * the License.
+ */
+package com.google.j2cl.transpiler.backend.kotlin
+
+import com.google.common.base.CaseFormat
+import com.google.j2cl.transpiler.ast.CompilationUnit
+import com.google.j2cl.transpiler.ast.DeclaredTypeDescriptor
+import com.google.j2cl.transpiler.ast.FieldDescriptor
+import com.google.j2cl.transpiler.ast.Method
+import com.google.j2cl.transpiler.ast.MethodDescriptor
+import com.google.j2cl.transpiler.ast.PrimitiveTypeDescriptor
+import com.google.j2cl.transpiler.ast.PrimitiveTypes
+import com.google.j2cl.transpiler.ast.Type
+import com.google.j2cl.transpiler.ast.TypeDeclaration
+import com.google.j2cl.transpiler.ast.TypeDescriptor
+import com.google.j2cl.transpiler.ast.TypeDescriptors.isJavaLangObject
+import com.google.j2cl.transpiler.ast.TypeDescriptors.isPrimitiveVoid
+import com.google.j2cl.transpiler.ast.Variable
+import com.google.j2cl.transpiler.backend.kotlin.common.buildList
+import com.google.j2cl.transpiler.backend.kotlin.common.letIf
+import com.google.j2cl.transpiler.backend.kotlin.objc.Rendering
+import com.google.j2cl.transpiler.backend.kotlin.objc.bindSource
+import com.google.j2cl.transpiler.backend.kotlin.objc.classNameRendering
+import com.google.j2cl.transpiler.backend.kotlin.objc.classRendering
+import com.google.j2cl.transpiler.backend.kotlin.objc.combineSources
+import com.google.j2cl.transpiler.backend.kotlin.objc.comment
+import com.google.j2cl.transpiler.backend.kotlin.objc.dependency
+import com.google.j2cl.transpiler.backend.kotlin.objc.functionDeclaration
+import com.google.j2cl.transpiler.backend.kotlin.objc.idRendering
+import com.google.j2cl.transpiler.backend.kotlin.objc.localImport
+import com.google.j2cl.transpiler.backend.kotlin.objc.nsCopyingRendering
+import com.google.j2cl.transpiler.backend.kotlin.objc.nsEnumTypedef
+import com.google.j2cl.transpiler.backend.kotlin.objc.nsInlineRendering
+import com.google.j2cl.transpiler.backend.kotlin.objc.nsMutableArrayRendering
+import com.google.j2cl.transpiler.backend.kotlin.objc.nsMutableDictionaryRendering
+import com.google.j2cl.transpiler.backend.kotlin.objc.nsMutableSetRendering
+import com.google.j2cl.transpiler.backend.kotlin.objc.nsNumberRendering
+import com.google.j2cl.transpiler.backend.kotlin.objc.nsObjectRendering
+import com.google.j2cl.transpiler.backend.kotlin.objc.nsStringRendering
+import com.google.j2cl.transpiler.backend.kotlin.objc.nsUIntegerRendering
+import com.google.j2cl.transpiler.backend.kotlin.objc.orEmpty
+import com.google.j2cl.transpiler.backend.kotlin.objc.protocolNameRendering
+import com.google.j2cl.transpiler.backend.kotlin.objc.rendering
+import com.google.j2cl.transpiler.backend.kotlin.objc.renderingWith
+import com.google.j2cl.transpiler.backend.kotlin.objc.returnStatement
+import com.google.j2cl.transpiler.backend.kotlin.objc.sourceWithDependencies
+import com.google.j2cl.transpiler.backend.kotlin.source.dotSeparated
+import com.google.j2cl.transpiler.backend.kotlin.source.emptyLineSeparated
+import com.google.j2cl.transpiler.backend.kotlin.source.ifNotEmpty
+import com.google.j2cl.transpiler.backend.kotlin.source.inAngleBrackets
+import com.google.j2cl.transpiler.backend.kotlin.source.join
+import com.google.j2cl.transpiler.backend.kotlin.source.plusNewLine
+import com.google.j2cl.transpiler.backend.kotlin.source.source
+import com.google.j2cl.transpiler.backend.kotlin.source.spaceSeparated
+
+internal val CompilationUnit.j2ObjCCompatHeaderSource
+  get() =
+    dependenciesAndDeclarationsSource.ifNotEmpty {
+      emptyLineSeparated(fileCommentSource, it).plusNewLine
+    }
+
+private val CompilationUnit.fileCommentSource
+  get() = comment(source("Generated by J2KT from \"${packageRelativePath}\""))
+
+private val CompilationUnit.dependenciesAndDeclarationsSource
+  get() = declarationsRendering.sourceWithDependencies
+
+private val CompilationUnit.declarationsRendering
+  get() = declarationsRenderings.combineSources(::emptyLineSeparated)
+
+private val CompilationUnit.declarationsRenderings
+  get() = types.flatMap { it.declarationsRenderings }
+
+private val Type.declarationsRenderings
+  get() =
+    buildList<Rendering> {
+      if (visibility.isPrivate || declaration.isKtNative) {
+        return@buildList
+      }
+
+      if (isEnum) {
+        add(nsEnumTypedefRendering)
+        addAll(enumGetFunctionRenderings)
+      }
+
+      addAll(methods.map { it.functionRendering })
+    }
+
+private val Type.nsEnumTypedefRendering
+  get() =
+    nsEnumTypedef(
+      name = declaration.objCEnumName,
+      type = nsUIntegerRendering,
+      values = enumFields.map { it.descriptor.objCEnumName }
+    )
+
+private val Type.enumGetFunctionRenderings
+  get() = enumFields.map { it.descriptor.enumGetFunctionRendering }
+
+private val FieldDescriptor.enumGetFunctionRendering
+  get() =
+    functionDeclaration(
+      modifiers = listOf(nsInlineRendering),
+      returnType = enclosingTypeDescriptor.objCRendering,
+      name = enumGetFunctionName,
+      parameters = listOf(),
+      statements = listOf(returnStatement(enumGetExpressionRendering))
+    )
+
+private val FieldDescriptor.enumGetFunctionName
+  get() = enclosingTypeDescriptor.typeDeclaration.objCName(forMember = true) + "_get_" + name!!
+
+private val FieldDescriptor.enumObjCName
+  get() = CaseFormat.UPPER_UNDERSCORE.to(CaseFormat.LOWER_CAMEL, name!!)
+
+private val FieldDescriptor.enumGetExpressionRendering
+  get() =
+    enclosingTypeDescriptor.typeDeclaration.objCNameRendering.bindSource { enumClassSource ->
+      rendering(dotSeparated(enumClassSource, source(enumObjCName)))
+    }
+
+private val Method.functionRendering
+  get() =
+    takeIf { it.isStatic && !it.isConstructor }
+      ?.toObjCNames()
+      ?.let { functionRendering(it) }
+      .orEmpty
+
+private fun Method.functionRendering(objCNames: MethodObjCNames) =
+  functionDeclaration(
+    modifiers = listOf(nsInlineRendering),
+    returnType = descriptor.returnTypeDescriptor.objCRendering,
+    name = descriptor.functionName(objCNames),
+    parameters = parameters.map { it.rendering },
+    statements = statementRenderings
+  )
+
+private fun MethodDescriptor.functionName(objCNames: MethodObjCNames) =
+  enclosingTypeDescriptor
+    .objCName(useId = true, forMember = true)
+    .plus("_")
+    .plus(objCNames.methodName ?: ktName)
+    .letIf(objCNames.parameterNames.isNotEmpty()) {
+      it.plus("_").plus(objCNames.parameterNames.map { it + "_" }.joinToString(""))
+    }
+
+private val Method.statementRenderings
+  get() =
+    if (isPrimitiveVoid(descriptor.returnTypeDescriptor)) listOf()
+    else listOf(returnStatement(rendering(source("0"))))
+
+private val Variable.rendering
+  get() =
+    typeDescriptor.objCRendering.bindSource { typeSource ->
+      rendering(spaceSeparated(typeSource, source(name.objCName)))
+    }
+
+private val TypeDeclaration.objCNameRendering
+  get() = objectiveCNameRendering ?: mappedObjCNameRendering ?: defaultObjCNameRendering
+
+private val TypeDeclaration.objectiveCNameRendering
+  get() =
+    objectiveCName?.let { if (isInterface) protocolNameRendering(it) else classNameRendering(it) }
+
+private val TypeDeclaration.mappedObjCNameRendering
+  get() =
+    when (qualifiedBinaryName) {
+      "java.lang.Object" -> nsObjectRendering
+      "java.lang.String" -> nsStringRendering
+      "java.lang.Class" -> classRendering
+      "java.lang.Number" -> nsNumberRendering
+      "java.lang.Cloneable" -> nsCopyingRendering
+      "java.util.List" -> nsMutableArrayRendering
+      "java.util.Set" -> nsMutableSetRendering
+      "java.util.Map" -> nsMutableDictionaryRendering
+      else -> null
+    }
+
+private val TypeDeclaration.defaultObjCNameRendering
+  get() =
+    defaultObjCName(forMember = false).let {
+      if (isInterface) protocolNameRendering(it) else classNameRendering(it)
+    }
+
+private val TypeDescriptor.objCRendering
+  get() =
+    when (this) {
+      is PrimitiveTypeDescriptor -> primitiveObjCRendering
+      is DeclaredTypeDescriptor -> declaredObjCRendering
+      // TODO: Handle TypeVariable and Array
+      else -> idRendering
+    }
+
+private val PrimitiveTypeDescriptor.primitiveObjCRendering
+  get() =
+    when (this) {
+      PrimitiveTypes.VOID -> rendering(source("void"))
+      else -> source("j$simpleSourceName") renderingWith dependency(j2ObjCTypesImport)
+    }
+
+private val DeclaredTypeDescriptor.declaredObjCRendering
+  get() =
+    when {
+      isJavaLangObject(this) -> idRendering
+      isInterface ->
+        typeDeclaration.objCNameRendering.bindSource {
+          rendering(join(source("id"), inAngleBrackets(it)))
+        }
+      else ->
+        typeDeclaration.objCNameRendering.bindSource { rendering(spaceSeparated(it, source("*"))) }
+    }
+
+private val j2ObjCTypesImport
+  get() = localImport("third_party/java_src/j2objc/jre_emul/Classes/J2ObjC_types.h")
+
+internal val TypeDeclaration.objCEnumName
+  get() = "${objCName}_Enum"
+
+internal val FieldDescriptor.objCEnumName
+  get() = "${enclosingTypeDescriptor.typeDeclaration.objCEnumName}_$name"
diff --git a/transpiler/java/com/google/j2cl/transpiler/backend/kotlin/KotlinGeneratorStage.kt b/transpiler/java/com/google/j2cl/transpiler/backend/kotlin/KotlinGeneratorStage.kt
@@ -37,12 +37,26 @@ class KotlinGeneratorStage(private val output: OutputUtils.Output, private val p
   }
 
   private fun generateOutputs(compilationUnit: CompilationUnit) {
-    val source = renderSource(compilationUnit)
+    generateKtOutputs(compilationUnit)
+    // TODO(b/263416948): Uncomment after cl/501829004 is submitted.
+    // generateObjCOutputs(compilationUnit)
+  }
+
+  private fun generateKtOutputs(compilationUnit: CompilationUnit) {
+    val source = ktSource(compilationUnit)
     val path = compilationUnit.packageRelativePath.replace(".java", ".kt")
     output.write(path, source)
   }
 
-  private fun renderSource(compilationUnit: CompilationUnit): String {
+  private fun generateObjCOutputs(compilationUnit: CompilationUnit) {
+    val source = compilationUnit.j2ObjCCompatHeaderSource
+    if (!source.isEmpty) {
+      val path = compilationUnit.packageRelativePath.replace(".java", "+J2ObjCCompat.h")
+      output.write(path, source.toString())
+    }
+  }
+
+  private fun ktSource(compilationUnit: CompilationUnit): String {
     val nameToIdentifierMap = compilationUnit.buildNameToIdentifierMap()
 
     val environment =

diff --git a/transpiler/java/com/google/j2cl/transpiler/backend/kotlin/ObjCNameRenderer.kt b/transpiler/java/com/google/j2cl/transpiler/backend/kotlin/ObjCNameRenderer.kt
@@ -130,7 +130,7 @@ private val TypeDeclaration.mappedObjCName: String?
       else -> null
     }
 
-private fun TypeDeclaration.defaultObjCName(forMember: Boolean): String =
+internal fun TypeDeclaration.defaultObjCName(forMember: Boolean): String =
   objCNamePrefix(forMember) + simpleObjCName
 
 private fun TypeDeclaration.objCNamePrefix(forMember: Boolean) =
@@ -158,12 +158,12 @@ private fun String.objCPackagePrefix(forMember: Boolean): String =
 private val String.titleCase
   get() = StringUtils.capitalize(this)
 
-private val String.objCName
+internal val String.objCName
   get() = replace('$', '_')
 
 private const val idObjCName = "id"
 
-private fun TypeDescriptor.objCName(useId: Boolean, forMember: Boolean): String =
+internal fun TypeDescriptor.objCName(useId: Boolean, forMember: Boolean): String =
   when (this) {
     is PrimitiveTypeDescriptor -> primitiveObjCName
     is ArrayTypeDescriptor -> arrayObjCName(forMember = forMember)

diff --git a/transpiler/java/com/google/j2cl/transpiler/backend/kotlin/objc/Rendering.kt b/transpiler/java/com/google/j2cl/transpiler/backend/kotlin/objc/Rendering.kt
@@ -19,6 +19,7 @@ import com.google.j2cl.transpiler.backend.kotlin.source.Source
 import com.google.j2cl.transpiler.backend.kotlin.source.commaSeparated
 import com.google.j2cl.transpiler.backend.kotlin.source.emptyLineSeparated
 import com.google.j2cl.transpiler.backend.kotlin.source.emptySource
+import com.google.j2cl.transpiler.backend.kotlin.source.ifEmpty
 import com.google.j2cl.transpiler.backend.kotlin.source.inCurlyBrackets
 import com.google.j2cl.transpiler.backend.kotlin.source.inNewLines
 import com.google.j2cl.transpiler.backend.kotlin.source.inRoundBrackets
@@ -62,32 +63,25 @@ fun Iterable<Rendering>.combineSources(fn: (Iterable<Source>) -> Source) = bindS
 val Rendering?.orEmpty
   get() = this ?: rendering(emptySource)
 
-fun declarator(type: Rendering, name: String, isPointer: Boolean) =
-  type.bindSource { typeSource ->
-    source(name).let { nameSource ->
-      rendering(
-        if (isPointer) join(typeSource, nameSource) else spaceSeparated(typeSource, nameSource)
-      )
-    }
-  }
-
-fun return_(expression: Rendering) =
-  expression.bindSource { expressionSource -> rendering(semicolonEnded(return_(expressionSource))) }
-
-fun function(
+fun functionDeclaration(
   modifiers: List<Rendering>,
-  declarator: Rendering,
+  returnType: Rendering,
+  name: String,
   parameters: List<Rendering>,
   statements: List<Rendering>
 ) =
   modifiers.bindSources { modifierSources ->
-    declarator.bindSource { declaratorSource ->
-      invocation(parameters).bindSource { invocationSource ->
+    returnType.bindSource { returnTypeSource ->
+      parameters.bindSources { parameterSources ->
         block(statements).bindSource { blockSource ->
           rendering(
             spaceSeparated(
               spaceSeparated(modifierSources),
-              join(declaratorSource, invocationSource),
+              returnTypeSource,
+              join(
+                source(name),
+                inRoundBrackets(commaSeparated(parameterSources).ifEmpty { source("void") })
+              ),
               blockSource
             )
           )
@@ -96,14 +90,8 @@ fun function(
     }
   }
 
-private fun invocation(parameters: List<Rendering>) =
-  parameters.bindSources { sources ->
-    rendering(
-      inRoundBrackets(
-        sources.toList().let { if (it.isEmpty()) source("void") else commaSeparated(it) }
-      )
-    )
-  }
-
-private fun block(statements: List<Rendering>) =
+fun block(statements: List<Rendering>) =
   statements.bindSources { sources -> rendering(inCurlyBrackets(inNewLines(sources))) }
+
+fun returnStatement(expression: Rendering) =
+  expression.bindSource { source -> rendering(semicolonEnded(return_(source))) }
diff --git a/transpiler/java/com/google/j2cl/transpiler/backend/kotlin/source/Source.kt b/transpiler/java/com/google/j2cl/transpiler/backend/kotlin/source/Source.kt
@@ -30,6 +30,8 @@ val emptySource
 val Source?.orEmpty
   get() = this ?: emptySource
 
+fun Source.ifEmpty(fn: () -> Source) = if (isEmpty) fn() else this
+
 fun Source.ifNotEmpty(fn: (Source) -> Source) = if (isEmpty) this else fn(this)
 
 fun source(string: String) = Source(string.isEmpty()) { it.append(string) }