[JS IR] Support the sourceMapEmbedSources setting (partially)

This doesn't work with external libraries yet (including stdlib).

compiler/ir/backend.js/src/org/jetbrains/kotlin/ir/backend/js/SourceMapsInfo.kt

@@ -0,0 +1,35 @@
+/*
+ * Copyright 2010-2022 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.ir.backend.js
+
+import org.jetbrains.kotlin.config.CompilerConfiguration
+import org.jetbrains.kotlin.js.config.JSConfigurationKeys
+import org.jetbrains.kotlin.js.config.SourceMapSourceEmbedding
+import java.io.File
+
+data class SourceMapsInfo(
+    val sourceMapPrefix: String,
+    val sourceRoots: List<String>,
+    val outputDir: File?,
+    val sourceMapContentEmbedding: SourceMapSourceEmbedding,
+) {
+    companion object {
+        fun from(configuration: CompilerConfiguration): SourceMapsInfo? =
+            if (configuration.getBoolean(JSConfigurationKeys.SOURCE_MAP)) {
+                SourceMapsInfo(
+                    configuration.get(JSConfigurationKeys.SOURCE_MAP_PREFIX, ""),
+                    configuration.get(JSConfigurationKeys.SOURCE_MAP_SOURCE_ROOTS, emptyList()),
+                    configuration.get(JSConfigurationKeys.OUTPUT_DIR),
+                    configuration.get(JSConfigurationKeys.SOURCE_MAP_EMBED_SOURCES, SourceMapSourceEmbedding.INLINING),
+                )
+            } else {
+                null
+            }
+    }
+}
+
+val JsCommonBackendContext.sourceMapsInfo: SourceMapsInfo?
+    get() = SourceMapsInfo.from(configuration)

compiler/ir/backend.js/src/org/jetbrains/kotlin/ir/backend/js/ic/JsExecutableProducer.kt

@@ -6,6 +6,7 @@
 package org.jetbrains.kotlin.ir.backend.js.ic
 
 import org.jetbrains.kotlin.ir.backend.js.CompilationOutputs
+import org.jetbrains.kotlin.ir.backend.js.SourceMapsInfo
 import org.jetbrains.kotlin.ir.backend.js.transformers.irToJs.*
 import org.jetbrains.kotlin.serialization.js.ModuleKind
 

compiler/ir/backend.js/src/org/jetbrains/kotlin/ir/backend/js/transformers/irToJs/IrModuleToJsTransformerTmp.kt

@@ -6,7 +6,6 @@
 package org.jetbrains.kotlin.ir.backend.js.transformers.irToJs
 
 import org.jetbrains.kotlin.config.CommonConfigurationKeys
-import org.jetbrains.kotlin.config.CompilerConfiguration
 import org.jetbrains.kotlin.ir.backend.js.*
 import org.jetbrains.kotlin.ir.backend.js.dce.eliminateDeadDeclarations
 import org.jetbrains.kotlin.ir.backend.js.export.*
@@ -471,23 +470,3 @@ fun generateSingleWrappedModuleBody(
     )
 }
 
-data class SourceMapsInfo(
-    val sourceMapPrefix: String,
-    val sourceRoots: List<String>,
-    val outputDir: File?,
-    val sourceMapContentEmbedding: SourceMapSourceEmbedding,
-) {
-    companion object {
-        fun from(configuration: CompilerConfiguration): SourceMapsInfo? =
-            if (configuration.getBoolean(JSConfigurationKeys.SOURCE_MAP)) {
-                SourceMapsInfo(
-                    configuration.get(JSConfigurationKeys.SOURCE_MAP_PREFIX, ""),
-                    configuration.get(JSConfigurationKeys.SOURCE_MAP_SOURCE_ROOTS, emptyList<String>()),
-                    configuration.get(JSConfigurationKeys.OUTPUT_DIR),
-                    configuration.get(JSConfigurationKeys.SOURCE_MAP_EMBED_SOURCES, SourceMapSourceEmbedding.INLINING),
-                )
-            } else {
-                null
-            }
-    }
-}

compiler/ir/backend.js/src/org/jetbrains/kotlin/ir/backend/js/transformers/irToJs/jsAstUtils.kt

@@ -9,8 +9,8 @@ import org.jetbrains.kotlin.backend.common.compilationException
 import org.jetbrains.kotlin.ir.IrElement
 import org.jetbrains.kotlin.ir.IrFileEntry
 import org.jetbrains.kotlin.ir.UNDEFINED_OFFSET
-import org.jetbrains.kotlin.ir.backend.js.JsIrBackendContext
 import org.jetbrains.kotlin.ir.backend.js.JsStatementOrigins
+import org.jetbrains.kotlin.ir.backend.js.sourceMapsInfo
 import org.jetbrains.kotlin.ir.backend.js.utils.*
 import org.jetbrains.kotlin.ir.declarations.IrClass
 import org.jetbrains.kotlin.ir.declarations.IrDeclaration
@@ -23,8 +23,13 @@ import org.jetbrains.kotlin.ir.visitors.acceptChildrenVoid
 import org.jetbrains.kotlin.ir.visitors.acceptVoid
 import org.jetbrains.kotlin.js.backend.ast.*
 import org.jetbrains.kotlin.js.common.isValidES5Identifier
+import org.jetbrains.kotlin.js.config.SourceMapSourceEmbedding
 import org.jetbrains.kotlin.util.OperatorNameConventions
 import org.jetbrains.kotlin.utils.addIfNotNull
+import java.io.FileInputStream
+import java.io.IOException
+import java.io.InputStreamReader
+import java.nio.charset.StandardCharsets
 
 fun jsVar(name: JsName, initializer: IrExpression?, context: JsGenerationContext): JsVars {
     val jsInitializer = initializer?.accept(IrElementToJsExpressionTransformer(), context)
@@ -492,17 +497,33 @@ internal fun <T : JsNode> T.withSource(node: IrElement, context: JsGenerationCon
 
 @Suppress("NOTHING_TO_INLINE")
 private inline fun <T : JsNode> T.addSourceInfoIfNeed(node: IrElement, context: JsGenerationContext) {
-    if (!context.staticContext.genSourcemaps) return
 
-    var cachedLocation = context.getLocationFromCache(node)
+    val sourceMapsInfo = context.staticContext.backendContext.sourceMapsInfo ?: return
-    if (cachedLocation == null) {
+
-        cachedLocation = node.getSourceInfo(context.currentFile.fileEntry) ?: return
+    val location = context.getLocationForIrElement(node) ?: return
-        context.saveLocationToCache(node, cachedLocation)
+
-    }
+    val isNodeFromCurrentModule = context.currentFile.module.descriptor == context.staticContext.backendContext.module
 
     // TODO maybe it's better to fix in JsExpressionStatement
     val locationTarget = if (this is JsExpressionStatement) this.expression else this
-    locationTarget.source = cachedLocation
+
+    locationTarget.source = when (sourceMapsInfo.sourceMapContentEmbedding) {
+        SourceMapSourceEmbedding.NEVER -> location
+        SourceMapSourceEmbedding.INLINING -> if (isNodeFromCurrentModule) location else location.withEmbeddedSource(context)
+        SourceMapSourceEmbedding.ALWAYS -> location.withEmbeddedSource(context)
+    }
+}
+
+private fun JsLocation.withEmbeddedSource(
+    context: JsGenerationContext
+) = JsLocationWithEmbeddedSource(this, identityObject = context.currentFile) {
+    try {
+        InputStreamReader(FileInputStream(file), StandardCharsets.UTF_8)
+    } catch (e: IOException) {
+        // TODO: If the source file is not available at path (e. g. it's an stdlib file), use heuristics to find it.
+        // If all heuristics fail, use dumpKotlinLike() on freshly deserialized IrFile.
+        null
+    }
 }
 
 fun IrElement.getSourceInfo(container: IrDeclaration): JsLocation? {

compiler/ir/backend.js/src/org/jetbrains/kotlin/ir/backend/js/utils/JsGenerationContext.kt

@@ -6,6 +6,7 @@
 package org.jetbrains.kotlin.ir.backend.js.utils
 
 import org.jetbrains.kotlin.ir.IrElement
+import org.jetbrains.kotlin.ir.backend.js.transformers.irToJs.getSourceInfo
 import org.jetbrains.kotlin.ir.declarations.*
 import org.jetbrains.kotlin.ir.expressions.IrLoop
 import org.jetbrains.kotlin.ir.expressions.IrReturnableBlock
@@ -86,7 +87,9 @@ class JsGenerationContext(
 
     fun checkIfHasAssociatedJsCode(symbol: IrFunctionSymbol): Boolean = staticContext.backendContext.getJsCodeForFunction(symbol) != null
 
-    fun getLocationFromCache(node: IrElement) = locationCache[node.startOffset]
+    fun getLocationForIrElement(irElement: IrElement): JsLocation? {
-
+        return locationCache.getOrPut(irElement.startOffset) {
-    fun saveLocationToCache(node: IrElement, location: JsLocation) = locationCache.put(node.startOffset, location)
+            irElement.getSourceInfo(currentFile.fileEntry) ?: return null
+        }
+    }
 }

compiler/ir/backend.js/src/org/jetbrains/kotlin/ir/backend/js/utils/JsStaticContext.kt

@@ -24,6 +24,4 @@ class JsStaticContext(
     val coroutineImplDeclaration = backendContext.ir.symbols.coroutineImpl.owner
 
     val initializerBlock = JsCompositeBlock()
-
-    val genSourcemaps = backendContext.configuration.getBoolean(JSConfigurationKeys.SOURCE_MAP)
 }

js/js.tests/test/org/jetbrains/kotlin/incremental/AbstractInvalidationTest.kt

@@ -20,7 +20,7 @@ import org.jetbrains.kotlin.ir.backend.js.*
 import org.jetbrains.kotlin.ir.backend.js.ic.*
 import org.jetbrains.kotlin.ir.backend.js.lower.serialization.ir.JsIrLinker
 import org.jetbrains.kotlin.ir.backend.js.transformers.irToJs.JsIrFragmentAndBinaryAst
-import org.jetbrains.kotlin.ir.backend.js.transformers.irToJs.SourceMapsInfo
+import org.jetbrains.kotlin.ir.backend.js.SourceMapsInfo
 import org.jetbrains.kotlin.ir.backend.js.transformers.irToJs.safeModuleName
 import org.jetbrains.kotlin.ir.declarations.IrFile
 import org.jetbrains.kotlin.ir.declarations.IrModuleFragment

js/js.tests/test/org/jetbrains/kotlin/js/test/converters/JsIrBackendFacade.kt

@@ -21,7 +21,7 @@ import org.jetbrains.kotlin.ir.backend.js.ic.JsExecutableProducer
 import org.jetbrains.kotlin.ir.backend.js.lower.serialization.ir.JsManglerDesc
 import org.jetbrains.kotlin.ir.backend.js.transformers.irToJs.IrModuleToJsTransformer
 import org.jetbrains.kotlin.ir.backend.js.transformers.irToJs.IrModuleToJsTransformerTmp
-import org.jetbrains.kotlin.ir.backend.js.transformers.irToJs.SourceMapsInfo
+import org.jetbrains.kotlin.ir.backend.js.SourceMapsInfo
 import org.jetbrains.kotlin.ir.backend.js.transformers.irToJs.TranslationMode
 import org.jetbrains.kotlin.ir.declarations.impl.IrFactoryImplForJsIC
 import org.jetbrains.kotlin.ir.util.IrMessageLogger

libraries/tools/kotlin-gradle-plugin-integration-tests/src/test/kotlin/org/jetbrains/kotlin/gradle/Kotlin2JsGradlePluginIT.kt

@@ -776,17 +776,21 @@ abstract class AbstractKotlin2JsGradlePluginIT(protected val irBackend: Boolean)
         }
     }
 
-    @DisplayName("sources can be embedded into source map")
+    @DisplayName("sources of all modules are embedded into source map")
-    @DisabledIf(
-        "org.jetbrains.kotlin.gradle.AbstractKotlin2JsGradlePluginIT#getIrBackend",
-        disabledReason = "Source maps are not supported in IR backend"
-    )
     @GradleTest
-    fun testKotlinJsSourceMapEmbedSources(gradleVersion: GradleVersion) {
+    fun testKotlinJsSourceMapEmbedSourcesAlways(gradleVersion: GradleVersion) {
         project("kotlin2JsProjectWithSourceMap", gradleVersion) {
             buildGradleKts.appendText(
                 """
-                |allprojects {
+                |project("lib") {
+                |   tasks.withType<KotlinJsCompile>() {
+                |        kotlinOptions {
+                |            sourceMap = true
+                |            sourceMapEmbedSources = "always"
+                |        }
+                |    }
+                |}
+                |project("app") {
                 |    tasks.withType<KotlinJsCompile> {
                 |        kotlinOptions.sourceMapEmbedSources = "always"
                 |    }
@@ -805,6 +809,42 @@ abstract class AbstractKotlin2JsGradlePluginIT(protected val irBackend: Boolean)
         }
     }
 
+    @DisplayName("only sources of external modules are embedded into source map")
+    @GradleTest
+    fun testKotlinJsSourceMapEmbedSourcesInlining(gradleVersion: GradleVersion) {
+        project("kotlin2JsProjectWithSourceMap", gradleVersion) {
+            buildGradleKts.appendText(
+                """
+                |project("lib") {
+                |   tasks.withType<KotlinJsCompile>() {
+                |        kotlinOptions {
+                |            sourceMap = true
+                |            sourceMapEmbedSources = "always"
+                |        }
+                |    }
+                |}
+                |project("app") {
+                |    tasks.withType<KotlinJsCompile> {
+                |        kotlinOptions.sourceMapEmbedSources = "inlining"
+                |    }
+                |}
+                |
+                """.trimMargin()
+            )
+            build(if (irBackend) "compileDevelopmentExecutableKotlinJs" else "compileKotlinJs") {
+                val mapFilePath = projectPath.resolve("build/js/packages/$projectName-app/kotlin/$projectName-app.js.map")
+                assertFileDoesNotContain(
+                    mapFilePath,
+                    "\"fun main(args: Array<String>) {"
+                )
+                assertFileContains(
+                    mapFilePath,
+                    "\"inline fun foo(): String {",
+                )
+            }
+        }
+    }
+
     @DisplayName("incremental compilation for js works")
     @GradleTest
     fun testIncrementalCompilation(gradleVersion: GradleVersion) {