From 374bb1b0215a09ad5ea6b867308c69d9f5a69194 Mon Sep 17 00:00:00 2001
From: Sergey Stoyanovsky <sergey.stoyanovsky@jetbrains.com>
Date: Thu, 30 Apr 2020 12:53:54 +0300
Subject: [PATCH] IDEA-239003 Fix PIEAE in NGram IDEA-CR-62219

Use SmartPsiElementPointer in NGramFileListener to survive reparsing

GitOrigin-RevId: c21626d554c550d6f8db5c8cf3a43d8a93e5b8d2
---
 .../com/intellij/completion/ngram/ModelRunnerWithCache.kt  | 7 ++++---
 .../src/com/intellij/completion/ngram/NGramFileListener.kt | 5 ++++-
 .../intellij/completion/ngram/NGramModelRunnerManager.kt   | 5 +++--
 3 files changed, 11 insertions(+), 6 deletions(-)

diff --git a/plugins/stats-collector/src/com/intellij/completion/ngram/ModelRunnerWithCache.kt b/plugins/stats-collector/src/com/intellij/completion/ngram/ModelRunnerWithCache.kt
index 15ef7d903104..4112955950a5 100644
--- a/plugins/stats-collector/src/com/intellij/completion/ngram/ModelRunnerWithCache.kt
+++ b/plugins/stats-collector/src/com/intellij/completion/ngram/ModelRunnerWithCache.kt
@@ -8,15 +8,16 @@ import com.intellij.completion.ngram.slp.modeling.Model
 import com.intellij.completion.ngram.slp.modeling.ngram.JMModel
 import com.intellij.completion.ngram.slp.modeling.runners.ModelRunner
 import com.intellij.psi.PsiFile
+import com.intellij.psi.SmartPsiElementPointer
 
 internal class ModelRunnerWithCache(model: Model = JMModel()) : ModelRunner(model) {
 
   private val myCache = FilePath2Tokens(this)
 
-  internal fun processFile(file: PsiFile) {
-    val filePath = file.virtualFile.path
+  internal fun processFile(filePointer: SmartPsiElementPointer<PsiFile>) {
+    val filePath = filePointer.virtualFile?.path ?: return
     if (filePath in myCache) return
-    val tokens = lexPsiFile(file, TEXT_RANGE_LIMIT)
+    val tokens = lexPsiFile(filePointer.element ?: return, TEXT_RANGE_LIMIT)
     myCache[filePath] = tokens
     learnTokens(tokens)
   }
diff --git a/plugins/stats-collector/src/com/intellij/completion/ngram/NGramFileListener.kt b/plugins/stats-collector/src/com/intellij/completion/ngram/NGramFileListener.kt
index 997616a34c0e..7569657695f4 100644
--- a/plugins/stats-collector/src/com/intellij/completion/ngram/NGramFileListener.kt
+++ b/plugins/stats-collector/src/com/intellij/completion/ngram/NGramFileListener.kt
@@ -9,6 +9,7 @@ import com.intellij.openapi.project.DumbService
 import com.intellij.openapi.project.Project
 import com.intellij.openapi.vfs.VirtualFile
 import com.intellij.psi.PsiManager
+import com.intellij.psi.SmartPointerManager
 
 class NGramFileListener(private val project: Project) : FileEditorManagerListener.Before {
 
@@ -16,9 +17,11 @@ class NGramFileListener(private val project: Project) : FileEditorManagerListene
     val psiFile = PsiManager.getInstance(project).findFile(file) ?: return
     val language = psiFile.language
     if (NGram.isSupported(language)) {
+      val filePointer = SmartPointerManager.createPointer(psiFile)
       ApplicationManager.getApplication().executeOnPooledThread {
         DumbService.getInstance(project).runReadActionInSmartMode {
-          ServiceManager.getService(project, NGramModelRunnerManager::class.java).processFile(psiFile, language)
+          ServiceManager.getService(project, NGramModelRunnerManager::class.java).processFile(filePointer, language)
+          SmartPointerManager.getInstance(project).removePointer(filePointer)
         }
       }
     }
diff --git a/plugins/stats-collector/src/com/intellij/completion/ngram/NGramModelRunnerManager.kt b/plugins/stats-collector/src/com/intellij/completion/ngram/NGramModelRunnerManager.kt
index 51233dd6b38c..e1564194e287 100644
--- a/plugins/stats-collector/src/com/intellij/completion/ngram/NGramModelRunnerManager.kt
+++ b/plugins/stats-collector/src/com/intellij/completion/ngram/NGramModelRunnerManager.kt
@@ -6,13 +6,14 @@ import com.intellij.lang.Language
 import com.intellij.openapi.components.ServiceManager
 import com.intellij.openapi.project.Project
 import com.intellij.psi.PsiFile
+import com.intellij.psi.SmartPsiElementPointer
 
 class NGramModelRunnerManager {
 
   private val myModelRunners: MutableMap<Language, ModelRunnerWithCache> = mutableMapOf()
 
-  fun processFile(file: PsiFile, language: Language) {
-    myModelRunners.getOrPut(language, { ModelRunnerWithCache() }).processFile(file)
+  fun processFile(filePointer: SmartPsiElementPointer<PsiFile>, language: Language) {
+    myModelRunners.getOrPut(language, { ModelRunnerWithCache() }).processFile(filePointer)
   }
 
   fun getModelRunnerForLanguage(language: Language): ModelRunner? {