Introduce cached ModuleDescriptor.implementingDescriptors

This property is used instead of findImplementingDescriptors,
which is basically too slow

idea/idea-jvm/src/org/jetbrains/kotlin/idea/run/KotlinMultiplatformJUnitRecognizer.kt

@@ -26,7 +26,7 @@ import org.jetbrains.kotlin.descriptors.TypeAliasDescriptor
 import org.jetbrains.kotlin.descriptors.annotations.AnnotationWithTarget
 import org.jetbrains.kotlin.idea.caches.resolve.analyze
 import org.jetbrains.kotlin.idea.caches.resolve.findModuleDescriptor
-import org.jetbrains.kotlin.idea.facet.findImplementingDescriptors
+import org.jetbrains.kotlin.idea.facet.implementingDescriptors
 import org.jetbrains.kotlin.idea.highlighter.markers.actualsFor
 import org.jetbrains.kotlin.idea.project.targetPlatform
 import org.jetbrains.kotlin.idea.util.module
@@ -41,7 +41,7 @@ class KotlinMultiplatformJUnitRecognizer : JUnitRecognizer() {
         if (origin.module?.targetPlatform !is TargetPlatformKind.Common) return false
 
         val moduleDescriptor = origin.containingKtFile.findModuleDescriptor()
-        val implModules = moduleDescriptor.findImplementingDescriptors()
+        val implModules = moduleDescriptor.implementingDescriptors
         if (implModules.isEmpty()) return false
 
         val bindingContext = origin.analyze(BodyResolveMode.PARTIAL)

idea/src/org/jetbrains/kotlin/idea/facet/facetUtils.kt

@@ -25,8 +25,10 @@ import com.intellij.openapi.projectRoots.JavaSdkVersion
 import com.intellij.openapi.projectRoots.ProjectJdkTable
 import com.intellij.openapi.roots.ModuleRootManager
 import com.intellij.openapi.roots.ModuleRootModel
+import com.intellij.openapi.roots.ProjectRootModificationTracker
 import com.intellij.openapi.util.io.FileUtil
 import com.intellij.openapi.util.text.StringUtil
+import com.intellij.psi.util.CachedValueProvider
 import org.jetbrains.kotlin.analyzer.ModuleInfo
 import org.jetbrains.kotlin.caches.resolve.KotlinCacheService
 import org.jetbrains.kotlin.cli.common.arguments.*
@@ -128,11 +130,9 @@ private fun Module.findImplementingModules(modelsProvider: IdeModifiableModelsPr
     }
 }
 
-fun ModuleDescriptor.findImplementingDescriptors(): List<ModuleDescriptor> {
-    val moduleSourceInfo = getCapability(ModuleInfo.Capability) as? ModuleSourceInfo ?: return emptyList()
-    val module = moduleSourceInfo.module
-    val modelsProvider = IdeModifiableModelsProviderImpl(module.project)
-    val implementingModules = module.findImplementingModules(modelsProvider)
+private fun Module.findImplementingDescriptors(moduleSourceInfo: ModuleSourceInfo): List<ModuleDescriptor> {
+    val modelsProvider = IdeModifiableModelsProviderImpl(project)
+    val implementingModules = findImplementingModules(modelsProvider)
     return implementingModules.mapNotNull {
         val implementingModuleInfo = when (moduleSourceInfo) {
             is ModuleProductionSourceInfo -> it.productionSourceInfo()
@@ -140,11 +140,23 @@ fun ModuleDescriptor.findImplementingDescriptors(): List<ModuleDescriptor> {
             else -> null
         }
         implementingModuleInfo?.let {
-            KotlinCacheService.getInstance(module.project).getResolutionFacadeByModuleInfo(it, it.platform)?.moduleDescriptor
+            KotlinCacheService.getInstance(project).getResolutionFacadeByModuleInfo(it, it.platform)?.moduleDescriptor
         }
     }
 }
 
+val ModuleDescriptor.implementingDescriptors: List<ModuleDescriptor>
+    get() {
+        val moduleSourceInfo = getCapability(ModuleInfo.Capability) as? ModuleSourceInfo ?: return emptyList()
+        val module = moduleSourceInfo.module
+        return module.cached(CachedValueProvider {
+            CachedValueProvider.Result(
+                module.findImplementingDescriptors(moduleSourceInfo),
+                ProjectRootModificationTracker.getInstance(module.project)
+            )
+        })
+    }
+
 fun Module.getOrCreateFacet(modelsProvider: IdeModifiableModelsProvider,
                             useProjectSettings: Boolean,
                             commitModel: Boolean = false): KotlinFacet {

idea/src/org/jetbrains/kotlin/idea/highlighter/PlatformExpectedAnnotator.kt

@@ -23,7 +23,7 @@ import org.jetbrains.kotlin.caches.resolve.KotlinCacheService
 import org.jetbrains.kotlin.descriptors.MemberDescriptor
 import org.jetbrains.kotlin.idea.caches.resolve.findModuleDescriptor
 import org.jetbrains.kotlin.idea.core.toDescriptor
-import org.jetbrains.kotlin.idea.facet.findImplementingDescriptors
+import org.jetbrains.kotlin.idea.facet.implementingDescriptors
 import org.jetbrains.kotlin.idea.project.TargetPlatformDetector
 import org.jetbrains.kotlin.psi.KtClassOrObject
 import org.jetbrains.kotlin.psi.KtDeclaration
@@ -41,7 +41,7 @@ class PlatformExpectedAnnotator : Annotator {
 
         if (TargetPlatformDetector.getPlatform(declaration.containingKtFile) !is TargetPlatform.Common) return
 
-        val implementingModules = declaration.findModuleDescriptor().findImplementingDescriptors()
+        val implementingModules = declaration.findModuleDescriptor().implementingDescriptors
         if (implementingModules.isEmpty()) return
 
         val descriptor = declaration.toDescriptor() as? MemberDescriptor ?: return

idea/src/org/jetbrains/kotlin/idea/highlighter/markers/HasActualMarker.kt

@@ -22,7 +22,7 @@ import org.jetbrains.kotlin.descriptors.*
 import org.jetbrains.kotlin.idea.caches.resolve.findModuleDescriptor
 import org.jetbrains.kotlin.idea.caches.resolve.unsafeResolveToDescriptor
 import org.jetbrains.kotlin.idea.core.toDescriptor
-import org.jetbrains.kotlin.idea.facet.findImplementingDescriptors
+import org.jetbrains.kotlin.idea.facet.implementingDescriptors
 import org.jetbrains.kotlin.psi.KtDeclaration
 import org.jetbrains.kotlin.resolve.DescriptorToSourceUtils
 import org.jetbrains.kotlin.resolve.MultiTargetPlatform
@@ -48,7 +48,7 @@ fun getPlatformActualTooltip(declaration: KtDeclaration): String? {
     val descriptor = declaration.toDescriptor() as? MemberDescriptor ?: return null
     val commonModuleDescriptor = declaration.containingKtFile.findModuleDescriptor()
 
-    val platformModulesWithActuals = commonModuleDescriptor.findImplementingDescriptors().filter {
+    val platformModulesWithActuals = commonModuleDescriptor.implementingDescriptors.filter {
         it.hasActualsFor(descriptor)
     }
     if (platformModulesWithActuals.isEmpty()) return null
@@ -74,7 +74,7 @@ private fun DeclarationDescriptor.actualsForExpected(): Collection<DeclarationDe
     if (this is MemberDescriptor) {
         if (!this.isExpect) return emptyList()
 
-        return module.findImplementingDescriptors().flatMap { it.actualsFor(this) }
+        return module.implementingDescriptors.flatMap { it.actualsFor(this) }
     }
 
     if (this is ValueParameterDescriptor) {

idea/src/org/jetbrains/kotlin/idea/highlighter/markers/KotlinLineMarkerProvider.kt

@@ -44,7 +44,7 @@ import org.jetbrains.kotlin.idea.caches.resolve.findModuleDescriptor
 import org.jetbrains.kotlin.idea.core.isInheritable
 import org.jetbrains.kotlin.idea.core.isOverridable
 import org.jetbrains.kotlin.idea.core.toDescriptor
-import org.jetbrains.kotlin.idea.facet.findImplementingDescriptors
+import org.jetbrains.kotlin.idea.facet.implementingDescriptors
 import org.jetbrains.kotlin.idea.util.ProjectRootsUtil
 import org.jetbrains.kotlin.lexer.KtTokens
 import org.jetbrains.kotlin.psi.*
@@ -292,7 +292,7 @@ private fun collectActualMarkers(declaration: KtNamedDeclaration,
     val descriptor = declaration.toDescriptor() as? MemberDescriptor ?: return
     val commonModuleDescriptor = declaration.containingKtFile.findModuleDescriptor()
 
-    if (commonModuleDescriptor.findImplementingDescriptors().none { it.hasActualsFor(descriptor) }) return
+    if (commonModuleDescriptor.implementingDescriptors.none { it.hasActualsFor(descriptor) }) return
 
     val anchor = declaration.nameIdentifier ?: declaration
 

idea/src/org/jetbrains/kotlin/idea/inspections/UnusedSymbolInspection.kt

@@ -53,7 +53,7 @@ import org.jetbrains.kotlin.idea.caches.resolve.findModuleDescriptor
 import org.jetbrains.kotlin.idea.caches.resolve.resolveToDescriptorIfAny
 import org.jetbrains.kotlin.idea.core.isInheritable
 import org.jetbrains.kotlin.idea.core.toDescriptor
-import org.jetbrains.kotlin.idea.facet.findImplementingDescriptors
+import org.jetbrains.kotlin.idea.facet.implementingDescriptors
 import org.jetbrains.kotlin.idea.findUsages.KotlinFindUsagesHandlerFactory
 import org.jetbrains.kotlin.idea.findUsages.handlers.KotlinFindClassUsagesHandler
 import org.jetbrains.kotlin.idea.highlighter.markers.hasActualsFor
@@ -334,7 +334,7 @@ class UnusedSymbolInspection : AbstractKotlinInspection() {
         descriptor as? MemberDescriptor ?: return false
         val commonModuleDescriptor = declaration.containingKtFile.findModuleDescriptor()
 
-        return commonModuleDescriptor.findImplementingDescriptors().any { it.hasActualsFor(descriptor) } ||
+        return commonModuleDescriptor.implementingDescriptors.any { it.hasActualsFor(descriptor) } ||
                commonModuleDescriptor.hasActualsFor(descriptor)
     }