[js2c] Fix ordering issue of TextMacro expansion

tools/js2c.py

 #!/usr/bin/env python
 #
 # Copyright 2012 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
@@ skipping 127 matching lines @@
     def expander(s):
       return ExpandMacros(s, macros)
     lines = ExpandMacroDefinition(lines, 0, name_pattern, macro, expander)
   return lines
 
 class TextMacro:
   def __init__(self, args, body):
     self.args = args
     self.body = body
   def expand(self, mapping):
-    result = self.body
-    for key, value in mapping.items():
-        result = result.replace(key, value)
-    return result
+    # Keys could be substrings of earlier values. To avoid unintended
+    # clobbering, apply all replacements simultaneously.
+    any_key_pattern = "|".join(re.escape(k) for k in mapping.iterkeys())
+    def replace(match):
+      return mapping[match.group(0)]
+    return re.sub(any_key_pattern, replace, self.body)
 
 class PythonMacro:
   def __init__(self, args, fun):
     self.args = args
     self.fun = fun
   def expand(self, mapping):
     args = []
     for arg in self.args:
       args.append(mapping[arg])
     return str(self.fun(*args))
@@ skipping 433 matching lines @@
   JS2C(args[2:],
        args[0],
        args[1],
        options.raw,
        options.startup_blob,
        options.js)
 
 
 if __name__ == "__main__":
   main()