Fix invalidating built-ins psi in consecutive test runs

idea/src/org/jetbrains/jet/plugin/references/BuiltInsReferenceResolver.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2010-2013 JetBrains s.r.o.
+ * Copyright 2010-2014 JetBrains s.r.o.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -33,6 +33,7 @@ import com.intellij.util.Function;
 import com.intellij.util.containers.ContainerUtil;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
+import org.jetbrains.annotations.TestOnly;
 import org.jetbrains.jet.asJava.LightClassUtil;
 import org.jetbrains.jet.context.ContextPackage;
 import org.jetbrains.jet.context.GlobalContextImpl;
@@ -80,6 +81,11 @@ public class BuiltInsReferenceResolver extends AbstractProjectComponent {
         });
     }
 
+    @TestOnly
+    public Set<JetFile> getBuiltInsSources() {
+        return builtInsSources;
+    }
+
     private void initialize() {
         assert bindingContext == null : "Attempt to initialize twice";
 

idea/tests/org/jetbrains/jet/plugin/JetLightCodeInsightFixtureTestCase.java

@@ -22,15 +22,22 @@ import com.intellij.openapi.actionSystem.ex.ActionManagerEx;
 import com.intellij.openapi.editor.ex.EditorEx;
 import com.intellij.openapi.startup.StartupManager;
 import com.intellij.openapi.util.io.FileUtil;
+import com.intellij.psi.FileViewProvider;
+import com.intellij.psi.PsiManager;
+import com.intellij.psi.impl.PsiManagerEx;
+import com.intellij.psi.impl.file.impl.FileManager;
 import com.intellij.testFramework.LightProjectDescriptor;
 import com.intellij.testFramework.fixtures.LightCodeInsightFixtureTestCase;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.jet.InTextDirectivesUtils;
+import org.jetbrains.jet.lang.psi.JetFile;
+import org.jetbrains.jet.plugin.references.BuiltInsReferenceResolver;
 import org.jetbrains.jet.utils.UtilsPackage;
 
 import java.io.File;
 import java.io.IOException;
 import java.util.List;
+import java.util.Set;
 
 public abstract class JetLightCodeInsightFixtureTestCase extends LightCodeInsightFixtureTestCase {
     @Override
@@ -39,6 +46,21 @@ public abstract class JetLightCodeInsightFixtureTestCase extends LightCodeInsigh
         ((StartupManagerImpl) StartupManager.getInstance(getProject())).runPostStartupActivities();
     }
 
+    @Override
+    protected void tearDown() throws Exception {
+        Set<JetFile> builtInsSources = getProject().getComponent(BuiltInsReferenceResolver.class).getBuiltInsSources();
+        FileManager fileManager = ((PsiManagerEx) PsiManager.getInstance(getProject())).getFileManager();
+
+        super.tearDown();
+
+        // Restore mapping between PsiFiles and VirtualFiles dropped in FileManager.cleanupForNextTest(),
+        // otherwise built-ins psi elements will become invalid in next test.
+        for (JetFile source : builtInsSources) {
+            FileViewProvider provider = source.getViewProvider();
+            fileManager.setViewProvider(provider.getVirtualFile(), provider);
+        }
+    }
+
     @NotNull
     @Override
     protected LightProjectDescriptor getProjectDescriptor() {