add a performance test for typing with multiple carets

(for IDEA-135620)

platform/platform-tests/testSrc/com/intellij/openapi/editor/EditorMultiCaretPerformanceTest.java

@@ -0,0 +1,35 @@
+/*
+ * Copyright 2000-2016 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.openapi.editor;
+
+import com.intellij.openapi.editor.impl.AbstractEditorTest;
+import com.intellij.openapi.util.text.StringUtil;
+import com.intellij.testFramework.PlatformTestUtil;
+
+public class EditorMultiCaretPerformanceTest extends AbstractEditorTest {
+  public void testTyping() throws Exception {
+    int caretCount = 1000;
+    int charactersToType = 100;
+    String initialText = StringUtil.repeat("<caret>\n", caretCount);
+    initText(initialText);
+    PlatformTestUtil.startPerformanceTest("Typing with large number of carets", 70000, () -> {
+      for (int i = 0; i < charactersToType; i++) {
+        type('a');
+      }
+    }).cpuBound().attempts(1).assertTiming();
+    checkResultByText(StringUtil.repeat(StringUtil.repeat("a", charactersToType) + "<caret>\n", caretCount));
+  }
+}