[FIR IDE] LC add caching to light facades

idea/idea-fir/src/org/jetbrains/kotlin/idea/caches/resolve/IDEKotlinAsJavaSupport.kt

@@ -6,25 +6,32 @@
 package org.jetbrains.kotlin.idea.caches.resolve
 
 import com.intellij.openapi.project.Project
+import com.intellij.openapi.util.Key
+import com.intellij.openapi.util.UserDataHolder
 import com.intellij.psi.PsiManager
 import com.intellij.psi.search.GlobalSearchScope
+import com.intellij.psi.util.CachedValueProvider
+import com.intellij.psi.util.CachedValuesManager
+import org.jetbrains.kotlin.analyzer.KotlinModificationTrackerService
 import org.jetbrains.kotlin.asJava.classes.KtLightClass
 import org.jetbrains.kotlin.idea.asJava.FirLightClassForFacade
+import org.jetbrains.kotlin.idea.asJava.classes.createFirLightClassNoCache
 import org.jetbrains.kotlin.idea.asJava.classes.getOrCreateFirLightClass
+import org.jetbrains.kotlin.idea.asJava.classes.getOrCreateFirLightFacade
 import org.jetbrains.kotlin.name.FqName
 import org.jetbrains.kotlin.psi.KtClassOrObject
+import org.jetbrains.kotlin.psi.KtFile
 import org.jetbrains.kotlin.psi.KtScript
 
 class IDEKotlinAsJavaFirSupport(project: Project) : IDEKotlinAsJavaSupport(project) {
 
-    //TODO Make caching
     override fun createLightClassForFacade(manager: PsiManager, facadeClassFqName: FqName, searchScope: GlobalSearchScope): KtLightClass? {
         val sources = findFilesForFacade(facadeClassFqName, searchScope)
             .filterNot { it.isCompiled }
 
         if (sources.isEmpty()) return null
 
-        return FirLightClassForFacade(manager, facadeClassFqName, sources)
+        return getOrCreateFirLightFacade(sources, facadeClassFqName)
     }
 
     override fun createLightClassForScript(script: KtScript): KtLightClass? = null

idea/idea-frontend-fir/src/org/jetbrains/kotlin/idea/asJava/classes/firLightClassUtils.kt

@@ -28,6 +28,7 @@ import org.jetbrains.kotlin.idea.frontend.api.symbols.markers.KtSymbolWithDeclar
 import org.jetbrains.kotlin.idea.frontend.api.types.KtClassType
 import org.jetbrains.kotlin.idea.frontend.api.types.KtType
 import org.jetbrains.kotlin.lexer.KtTokens
+import org.jetbrains.kotlin.name.FqName
 import org.jetbrains.kotlin.psi.*
 import org.jetbrains.kotlin.psi.psiUtil.containingClass
 import java.util.*
@@ -79,6 +80,29 @@ fun createFirLightClassNoCache(classOrObject: KtClassOrObject): KtLightClass? {
     }
 }
 
+fun getOrCreateFirLightFacade(
+    ktFiles: List<KtFile>,
+    facadeClassFqName: FqName,
+): FirLightClassForFacade? {
+    val firstFile = ktFiles.firstOrNull() ?: return null
+    //TODO Make caching keyed by all files
+    return CachedValuesManager.getCachedValue(firstFile) {
+        CachedValueProvider.Result
+            .create(
+                getOrCreateFirLightFacadeNoCache(ktFiles, facadeClassFqName),
+                KotlinModificationTrackerService.getInstance(firstFile.project).outOfBlockModificationTracker
+            )
+    }
+}
+
+fun getOrCreateFirLightFacadeNoCache(
+    ktFiles: List<KtFile>,
+    facadeClassFqName: FqName,
+): FirLightClassForFacade? {
+    val firstFile = ktFiles.firstOrNull() ?: return null
+    return FirLightClassForFacade(firstFile.manager, facadeClassFqName, ktFiles)
+}
+
 
 private fun lightClassForEnumEntry(ktEnumEntry: KtEnumEntry): KtLightClass? {
     if (ktEnumEntry.body == null) return null