From e1627493660f5a893604afe51c31fd716fa5c4f4 Mon Sep 17 00:00:00 2001
From: Denis Zharkov <denis.zharkov@jetbrains.com>
Date: Thu, 22 Mar 2018 13:07:59 +0300
Subject: [PATCH] Add a cache for PsiBasedClassResolver instances

The PsiBasedClassResolver constructor isn't very cheap to call
because it runs computation of conflicting names each time

Again, this is helpful for Spring-interop because PsiBasedClassResolver
is used very frequently there

 #KT-23380 Fixed
---
 .../IdeLightClassInheritanceHelper.kt         |  2 +-
 .../idea/search/PsiBasedClassResolver.kt      | 28 +++++++++++++++++--
 .../KotlinAnnotatedElementsSearcher.kt        |  2 +-
 3 files changed, 28 insertions(+), 4 deletions(-)

diff --git a/idea/idea-analysis/src/org/jetbrains/kotlin/idea/caches/lightClasses/IdeLightClassInheritanceHelper.kt b/idea/idea-analysis/src/org/jetbrains/kotlin/idea/caches/lightClasses/IdeLightClassInheritanceHelper.kt
index 71dc8af70bc..b2d5014cc65 100644
--- a/idea/idea-analysis/src/org/jetbrains/kotlin/idea/caches/lightClasses/IdeLightClassInheritanceHelper.kt
+++ b/idea/idea-analysis/src/org/jetbrains/kotlin/idea/caches/lightClasses/IdeLightClassInheritanceHelper.kt
@@ -52,7 +52,7 @@ class IdeLightClassInheritanceHelper : LightClassInheritanceHelper {
     }
 
     private fun isAmongEntries(baseClass: PsiClass, entries: List<KtSuperTypeListEntry>): ImpreciseResolveResult {
-        val psiBasedResolver = PsiBasedClassResolver(baseClass)
+        val psiBasedResolver = PsiBasedClassResolver.getInstance(baseClass)
         entries@ for (entry in entries) {
             val reference: KtSimpleNameExpression = entry.typeAsUserType?.referenceExpression ?: continue@entries
             when (psiBasedResolver.canBeTargetReference(reference)) {
diff --git a/idea/idea-analysis/src/org/jetbrains/kotlin/idea/search/PsiBasedClassResolver.kt b/idea/idea-analysis/src/org/jetbrains/kotlin/idea/search/PsiBasedClassResolver.kt
index 3b68fc3a692..ffd8b3fa587 100644
--- a/idea/idea-analysis/src/org/jetbrains/kotlin/idea/search/PsiBasedClassResolver.kt
+++ b/idea/idea-analysis/src/org/jetbrains/kotlin/idea/search/PsiBasedClassResolver.kt
@@ -16,9 +16,14 @@
 
 package org.jetbrains.kotlin.idea.search
 
+import com.intellij.openapi.util.Key
 import com.intellij.psi.PsiClass
 import com.intellij.psi.PsiModifier
 import com.intellij.psi.search.PsiShortNamesCache
+import com.intellij.psi.util.CachedValue
+import com.intellij.psi.util.CachedValueProvider
+import com.intellij.psi.util.CachedValuesManager
+import com.intellij.psi.util.PsiModificationTracker
 import org.jetbrains.annotations.TestOnly
 import org.jetbrains.kotlin.asJava.ImpreciseResolveResult
 import org.jetbrains.kotlin.asJava.ImpreciseResolveResult.*
@@ -61,9 +66,28 @@ class PsiBasedClassResolver @TestOnly constructor(private val targetClassFqName:
         @TestOnly val attempts = AtomicInteger()
         @TestOnly val trueHits = AtomicInteger()
         @TestOnly val falseHits = AtomicInteger()
+
+        private val PSI_BASED_CLASS_RESOLVER_KEY = Key<CachedValue<PsiBasedClassResolver>>("PsiBasedClassResolver")
+
+        fun getInstance(target: PsiClass): PsiBasedClassResolver {
+            target.getUserData(PSI_BASED_CLASS_RESOLVER_KEY)?.let { return it.value }
+
+            val cachedValue = CachedValuesManager.getManager(target.project).createCachedValue(
+                {
+                    CachedValueProvider.Result(
+                        PsiBasedClassResolver(target),
+                        PsiModificationTracker.OUT_OF_CODE_BLOCK_MODIFICATION_COUNT
+                    )
+                }, false
+            )
+
+            target.putUserData(PSI_BASED_CLASS_RESOLVER_KEY, cachedValue)
+
+            return cachedValue.value
+        }
     }
 
-    constructor(target: PsiClass): this(target.qualifiedName ?: "") {
+    private constructor(target: PsiClass): this(target.qualifiedName ?: "") {
         if (target.qualifiedName == null || target.containingClass != null || targetPackage.isEmpty()) {
             forceAmbiguity = true
             return
@@ -239,4 +263,4 @@ private fun KtFile.getDefaultImports(): List<ImportPath> {
     return TargetPlatformDetector.getPlatform(this).getDefaultImports(
             versionSettings.supportsFeature(LanguageFeature.DefaultImportOfPackageKotlinComparisons)
     )
-}
\ No newline at end of file
+}
diff --git a/idea/src/org/jetbrains/kotlin/idea/search/ideaExtensions/KotlinAnnotatedElementsSearcher.kt b/idea/src/org/jetbrains/kotlin/idea/search/ideaExtensions/KotlinAnnotatedElementsSearcher.kt
index 8ec81434948..296cc08e590 100644
--- a/idea/src/org/jetbrains/kotlin/idea/search/ideaExtensions/KotlinAnnotatedElementsSearcher.kt
+++ b/idea/src/org/jetbrains/kotlin/idea/search/ideaExtensions/KotlinAnnotatedElementsSearcher.kt
@@ -78,7 +78,7 @@ class KotlinAnnotatedElementsSearcher : QueryExecutor<PsiModifierListOwner, Anno
                                     consumer: (KtDeclaration) -> Boolean): Boolean {
             assert(annClass.isAnnotationType) { "Annotation type should be passed to annotated members search" }
 
-            val psiBasedClassResolver = PsiBasedClassResolver(annClass)
+            val psiBasedClassResolver = PsiBasedClassResolver.getInstance(annClass)
             val annotationFQN = annClass.qualifiedName!!
 
             val candidates = getKotlinAnnotationCandidates(annClass, useScope)