Refactor LightClassDataProvider: drop LightClassDataProvider class

Move code to inheritors
Improve api to avoid getting empty file lists in random places

compiler/light-classes/src/org/jetbrains/kotlin/asJava/builder/LightClassBuilder.kt

@@ -40,14 +40,13 @@ import org.jetbrains.kotlin.resolve.diagnostics.Diagnostics
 data class LightClassBuilderResult(val stub: PsiJavaFileStub, val bindingContext: BindingContext, val diagnostics: Diagnostics)
 
 fun buildLightClass(
-        project: Project,
         packageFqName: FqName,
         files: Collection<KtFile>,
         generateClassFilter: GenerationState.GenerateClassFilter,
         context: LightClassConstructionContext,
         generate: (state: GenerationState, files: Collection<KtFile>) -> Unit
 ): LightClassBuilderResult {
-
+    val project = files.first().project
     val javaFileStub = createJavaFileStub(project, packageFqName, files)
     val bindingContext: BindingContext
 
@@ -64,7 +63,7 @@ fun buildLightClass(
                 KotlinLightClassBuilderFactory(stubStack),
                 context.module,
                 context.bindingContext,
-                files.toMutableList(),
+                files.toList(),
                 CompilerConfiguration.EMPTY,
                 generateClassFilter,
                 wantsDiagnostics = false
@@ -93,7 +92,7 @@ fun buildLightClass(
 }
 
 private fun createJavaFileStub(project: Project, packageFqName: FqName, files: Collection<KtFile>): PsiJavaFileStub {
-    val javaFileStub = PsiJavaFileStubImpl(packageFqName.asString(), true)
+    val javaFileStub = PsiJavaFileStubImpl(packageFqName.asString(), /*compiled = */true)
     javaFileStub.psiFactory = ClsWrapperStubPsiFactory.INSTANCE
 
     val manager = PsiManager.getInstance(project)
@@ -124,4 +123,4 @@ private fun logErrorWithOSInfo(cause: Throwable?, fqName: FqName, virtualFile: V
     )
 }
 
-private val LOG = Logger.getInstance(LightClassDataProvider::class.java)
+private val LOG = Logger.getInstance(LightClassBuilderResult::class.java)

compiler/light-classes/src/org/jetbrains/kotlin/asJava/builder/LightClassDataProvider.kt

@@ -36,37 +36,14 @@ import org.jetbrains.kotlin.psi.KtPsiUtil
 import org.jetbrains.kotlin.psi.KtScript
 import org.jetbrains.kotlin.psi.psiUtil.isAncestor
 
-abstract class LightClassDataProvider<T : LightClassDataHolder>(
+class LightClassDataProviderForClassOrObject(private val classOrObject: KtClassOrObject) : CachedValueProvider<LightClassDataHolder> {
-        private val project: Project
-) : CachedValueProvider<T> {
-    abstract val isLocal: Boolean
 
-    open val valueAbsent: Boolean = false
+    private fun computeLightClassData(): LightClassDataHolder {
-
-    override fun compute(): CachedValueProvider.Result<T>? {
-        if (valueAbsent) return null
-
-        return CachedValueProvider.Result.create(
-                computeLightClassData(),
-                if (isLocal) PsiModificationTracker.MODIFICATION_COUNT else PsiModificationTracker.OUT_OF_CODE_BLOCK_MODIFICATION_COUNT
-        )
-    }
-
-    abstract fun computeLightClassData(): T
-}
-
-class LightClassDataProviderForClassOrObject(private val classOrObject: KtClassOrObject) :
-        LightClassDataProvider<LightClassDataHolder>(classOrObject.project) {
-
-    override val isLocal: Boolean get() = classOrObject.isLocal
-
-
-    override fun computeLightClassData(): LightClassDataHolder {
         val file = classOrObject.containingKtFile
         val packageFqName = file.packageFqName
         return LightClassGenerationSupport.getInstance(classOrObject.project).createLightClassDataHolderForClassOrObject(classOrObject) {
             constructionContext ->
-            buildLightClass(classOrObject.project, packageFqName, listOf(file), ClassFilterForClassOrObject(classOrObject), constructionContext) {
+            buildLightClass(packageFqName, listOf(file), ClassFilterForClassOrObject(classOrObject), constructionContext) {
                 state, files ->
                 val packageCodegen = state.factory.forPackage(packageFqName, files)
                 val packagePartType = state.fileClassesProvider.getFileClassType(file)
@@ -77,6 +54,13 @@ class LightClassDataProviderForClassOrObject(private val classOrObject: KtClassO
         }
     }
 
+    override fun compute(): CachedValueProvider.Result<LightClassDataHolder>? {
+        return CachedValueProvider.Result.create(
+                computeLightClassData(),
+                if (classOrObject.isLocal()) PsiModificationTracker.MODIFICATION_COUNT else PsiModificationTracker.OUT_OF_CODE_BLOCK_MODIFICATION_COUNT
+        )
+    }
+
     override fun toString(): String {
         return this::class.java.name + " for " + classOrObject.name
     }
@@ -84,27 +68,21 @@ class LightClassDataProviderForClassOrObject(private val classOrObject: KtClassO
 
 sealed class LightClassDataProviderForFileFacade constructor(
         protected val project: Project, protected val facadeFqName: FqName
-) : LightClassDataProvider<LightClassDataHolder>(project) {
+) : CachedValueProvider<LightClassDataHolder> {
-    override val isLocal: Boolean get() = false
+    abstract fun findFiles(): Collection<KtFile>
-    abstract val files: Collection<KtFile>
 
-    override val valueAbsent: Boolean
+    private fun computeLightClassData(files: Collection<KtFile>): LightClassDataHolder {
-        get() = files.isEmpty()
-
-    override fun computeLightClassData(): LightClassDataHolder {
         return LightClassGenerationSupport.getInstance(project).createLightClassDataHolderForFacade(files) {
             constructionContext ->
-            buildLightClass(project, facadeFqName.parent(), files, ClassFilterForFacade, constructionContext) generate@ {
+            buildLightClass(facadeFqName.parent(), files, ClassFilterForFacade, constructionContext) generate@ {
                 state, files ->
-                if (!files.isEmpty()) {
+                val representativeFile = files.first()
-                    val representativeFile = files.iterator().next()
+                val fileClassInfo = NoResolveFileClassesProvider.getFileClassInfo(representativeFile)
-                    val fileClassInfo = NoResolveFileClassesProvider.getFileClassInfo(representativeFile)
+                if (!fileClassInfo.withJvmMultifileClass) {
-                    if (!fileClassInfo.withJvmMultifileClass) {
+                    val codegen = state.factory.forPackage(representativeFile.packageFqName, files)
-                        val codegen = state.factory.forPackage(representativeFile.packageFqName, files)
+                    codegen.generate(CompilationErrorHandler.THROW_EXCEPTION)
-                        codegen.generate(CompilationErrorHandler.THROW_EXCEPTION)
+                    state.factory.asList()
-                        state.factory.asList()
+                    return@generate
-                        return@generate
-                    }
                 }
 
                 val codegen = state.factory.forMultifileClass(facadeFqName, files)
@@ -114,6 +92,16 @@ sealed class LightClassDataProviderForFileFacade constructor(
         }
     }
 
+    override fun compute(): CachedValueProvider.Result<LightClassDataHolder>? {
+        val files = findFiles()
+        if (files.isEmpty()) return null
+
+        return CachedValueProvider.Result.create(
+                computeLightClassData(files),
+                PsiModificationTracker.OUT_OF_CODE_BLOCK_MODIFICATION_COUNT
+        )
+    }
+
     override fun toString(): String {
         return this::class.java.name + " for $facadeFqName"
     }
@@ -124,8 +112,7 @@ sealed class LightClassDataProviderForFileFacade constructor(
             facadeFqName: FqName,
             private val searchScope: GlobalSearchScope
     ) : LightClassDataProviderForFileFacade(project, facadeFqName) {
-        override val files: Collection<KtFile>
+        override fun findFiles() = LightClassGenerationSupport.getInstance(project).findFilesForFacade(facadeFqName, searchScope)
-            get() = LightClassGenerationSupport.getInstance(project).findFilesForFacade(facadeFqName, searchScope)
     }
 
     // create delegate by single file
@@ -134,8 +121,7 @@ sealed class LightClassDataProviderForFileFacade constructor(
             facadeFqName: FqName,
             private val file: KtFile
     ) : LightClassDataProviderForFileFacade(project, facadeFqName) {
-        override val files: Collection<KtFile>
+        override fun findFiles() = listOf(file)
-            get() = listOf(file)
     }
 }