Recommitting http://codereview.chromium.org/8310016/

compiler/javatests/com/google/dart/compiler/parser/TruncatedSourceParserTest.java

Index: compiler/javatests/com/google/dart/compiler/parser/TruncatedSourceParserTest.java
===================================================================
--- compiler/javatests/com/google/dart/compiler/parser/TruncatedSourceParserTest.java	(revision 0)
+++ compiler/javatests/com/google/dart/compiler/parser/TruncatedSourceParserTest.java	(revision 0)
@@ -0,0 +1,153 @@
+// Copyright (c) 2011, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+package com.google.dart.compiler.parser;
+
+import com.google.dart.compiler.DartCompilationError;
+import com.google.dart.compiler.DartCompilerListenerTest;
+import com.google.dart.compiler.DartSourceTest;
+import com.google.dart.compiler.ast.DartUnit;
+
+public class TruncatedSourceParserTest extends AbstractParserTest {
+
+  /**
+   * Performs parsing in a separate thread such that the test can detect infinite loop.
+   */
+  private class ParserThread extends Thread {
+    private final Object lock = new Object();
+    private final String srcName;
+    private int state = 0;
+    private String srcCode;
+    private DartUnit result;
+
+    /**
+     * Listener that ignores errors because this is a stress test
+     */
+    private DartCompilerListenerTest listener = new DartCompilerListenerTest("") {
+      @Override
+      public void checkAllErrorsReported() {
+      }
+
+      @Override
+      public void compilationError(DartCompilationError event) {
+      }
+    };
+
+    public ParserThread(String srcName) {
+      super("Parsing " + srcName);
+      this.srcName = srcName;
+    }
+
+    /**
+     * Queue the specified source to be parsed on a separate thread. Wait up to 10 seconds for the
+     * result
+     * 
+     * @return <code>true</code> if finished parsing
+     */
+    public boolean parse(String srcCode) {
+      assert (srcCode != null);
+      assert (state == 0);
+      synchronized (lock) {
+        this.srcCode = srcCode;
+        result = null;
+        state = 1;
+        lock.notifyAll();
+        try {
+          lock.wait(10000);
+        } catch (InterruptedException e) {
+          // Fall through
+        }
+        return state == 0;
+      }
+    }
+
+    /**
+     * Parse source code in the background
+     */
+    @Override
+    public void run() {
+      while (true) {
+        DartSourceTest src;
+        ParserContext context;
+        synchronized (lock) {
+          while (state == 0) {
+            try {
+              lock.wait();
+            } catch (InterruptedException e) {
+              // Fall through
+            }
+          }
+          if (state == 2) {
+            return;
+          }
+          src = new DartSourceTest(srcName, srcCode, null);
+          context = makeParserContext(src, srcCode, listener);
+        }
+        DartUnit unit = makeParser(context).parseUnit(src);
+        synchronized (lock) {
+          if (state == 2) {
+            return;
+          }
+          state = 0;
+          result = unit;
+          lock.notifyAll();
+        }
+      }
+    }
+
+    /**
+     * Signal the background thread to terminate
+     */
+    public void stopParsing() {
+      synchronized (lock) {
+        state = 2;
+        lock.notify();
+      }
+    }
+  }
+
+  @Override
+  public void testStringsErrors() {
+    parseUnit("StringsErrorsNegativeTest.dart");
+  }
+
+  @Override
+  public void testTiming() {
+    // Skip
+  }
+
+  @Override
+  protected DartUnit parseUnit(String srcName, String srcCode) {
+    // System.out.print(srcName);
+    ParserThread thread = new ParserThread(srcName);
+    thread.start();
+    int eol = 0;
+    for (int index = 0; index < srcCode.length(); index++) {
+      if (eol == index) {
+        eol++;
+        while (eol < srcCode.length()) {
+          char ch = srcCode.charAt(eol);
+          if (ch == '\r' || ch == '\n') {
+            break;
+          }
+          eol++;
+        }
+      }
+      String modifiedSrcCode = srcCode.substring(0, index);
+      if (!thread.parse(modifiedSrcCode)) {
+        // System.out.println();
+        fail("Failed to finish parsing " + srcName + "\n" + modifiedSrcCode);
+      }
+      modifiedSrcCode += srcCode.substring(eol);
+      if (!thread.parse(modifiedSrcCode)) {
+        // System.out.println();
+        fail("Failed to finish parsing " + srcName + "\n" + modifiedSrcCode);
+      }
+      // System.out.print('.');
+    }
+    thread.stopParsing();
+    // System.out.println();
+    return thread.result;
+  }
+}