Fix pre-parsing of 'use strict' directive after string literals.

R=ulan@chromium.org
TEST=mjsunit/regress/regress-parse-use-strict

Review URL: https://codereview.chromium.org/27025002

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@17164 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/preparser.h

@@ -444,7 +444,7 @@ class PreParser {
     }
 
     bool IsStringLiteral() {
-      return code_ != kUnknownStatement;
+      return code_ == kStringLiteralExpressionStatement;
     }
 
     bool IsUseStrictLiteral() {

test/mjsunit/regress/regress-parse-use-strict.js

+// Copyright 2013 the V8 project authors. All rights reserved.
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+//       notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+//       copyright notice, this list of conditions and the following
+//       disclaimer in the documentation and/or other materials provided
+//       with the distribution.
+//     * Neither the name of Google Inc. nor the names of its
+//       contributors may be used to endorse or promote products derived
+//       from this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+// Filler long enough to trigger lazy parsing.
+var filler = "/*" + new Array(1024).join('x') + "*/";
+
+// Snippet trying to switch to strict mode.
+var strict = '"use strict"; with({}) {}';
+
+// Test switching to strict mode after string literal.
+assertThrows('function f() { "use sanity";' + strict + '}');
+assertThrows('function f() { "use sanity";' + strict + filler + '}');
+
+// Test switching to strict mode after function declaration.
+// We must use eval instead of assertDoesNotThrow here to make sure that
+// lazy parsing is triggered. Otherwise the bug won't reproduce.
+eval('function f() { function g() {}' + strict + '}');
+eval('function f() { function g() {}' + strict + filler + '}');