IDEA-88652 make FileTypeIndex aware of newly added file types

platform/lang-impl/src/com/intellij/psi/search/FileTypeIndex.java

@@ -65,7 +65,12 @@ public class FileTypeIndex extends ScalarIndexExtension<FileType>
 
   @Override
   public int getVersion() {
-    return 1;
+    FileType[] types = myFileTypeManager.getRegisteredFileTypes();
+    int version = 1;
+    for (FileType type : types) {
+      version += type.getName().hashCode();
+    }
+    return version;
   }
 
   @Override

platform/platform-tests/testSrc/com/intellij/psi/search/FileTypeIndexTest.java

@@ -0,0 +1,65 @@
+/*
+ * Copyright 2000-2012 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.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.intellij.psi.search;
+
+import com.intellij.openapi.fileTypes.FileNameMatcher;
+import com.intellij.openapi.fileTypes.FileType;
+import com.intellij.openapi.fileTypes.FileTypeManager;
+import com.intellij.openapi.fileTypes.ex.FakeFileType;
+import com.intellij.openapi.vfs.VirtualFile;
+import com.intellij.testFramework.PlatformTestCase;
+import com.intellij.testFramework.fixtures.LightPlatformCodeInsightFixtureTestCase;
+import org.jetbrains.annotations.NotNull;
+
+import java.util.Collections;
+
+/**
+ * @author Dmitry Avdeev
+ *         Date: 7/24/12
+ */
+public class FileTypeIndexTest extends LightPlatformCodeInsightFixtureTestCase {
+
+  public FileTypeIndexTest() {
+    PlatformTestCase.initPlatformLangPrefix();
+  }
+
+  public void testAddFileType() throws Exception {
+    FileType foo = new FakeFileType() {
+      @Override
+      public boolean isMyFileType(VirtualFile file) {
+        return true;
+      }
+
+      @NotNull
+      @Override
+      public String getName() {
+        return "foo";
+      }
+
+      @NotNull
+      @Override
+      public String getDescription() {
+        return "";
+      }
+    };
+    FileTypeIndex index = new FileTypeIndex(FileTypeManager.getInstance());
+    int version = index.getVersion();
+
+    FileTypeManager.getInstance().registerFileType(foo, Collections.<FileNameMatcher>emptyList());
+
+    assertNotSame(version, index.getVersion());
+  }
+}