Allow substitution of messages as variables in other messages.

grit/format/c_format.py

 #!/usr/bin/env python
 # Copyright (c) 2012 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 """Formats as a .C file for compilation.
 """
 
 import os
 import re
 import types
 
 from grit import util
 from grit.format import interface
 from grit.node import io
 
 
 class TopLevel(interface.ItemFormatter):
   """Writes out the required preamble for C files."""
 
-  def Format(self, item, lang='en', begin_item=True, output_dir='.'):
+  def Format(self, item, lang='en', output_dir='.'):
+    """Format the C file header."""
     assert isinstance(lang, types.StringTypes)
-    if not begin_item:
-      return ''
-    else:
-      # Find the location of the resource header file, so that we can include
-      # it.
-      resource_header = 'resource.h'  # fall back to this
-      for output in item.GetRoot().GetOutputFiles():
-        if output.attrs['type'] == 'rc_header':
-          resource_header = os.path.abspath(output.GetOutputFilename())
-          resource_header = util.MakeRelativePath(output_dir,
-                                                  resource_header)
-      return """//  Copyright %d Google Inc. All Rights Reserved.
+    # Find the location of the resource header file, so that we can include
+    # it.
+    resource_header = 'resource.h'  # fall back to this
+    for output in item.GetRoot().GetOutputFiles():
+      if output.attrs['type'] == 'rc_header':
+        resource_header = os.path.abspath(output.GetOutputFilename())
+        resource_header = util.MakeRelativePath(output_dir,
+                                                resource_header)
+    return """//  Copyright %d Google Inc. All Rights Reserved.
 // This file is automatically generated by GRIT.  Do not edit.
 
 #include "%s"
 
 // All strings are UTF-8
 """ % (util.GetCurrentYear(), resource_header)
 # end Format() function
 
 
 class StringTable(interface.ItemFormatter):
   """Outputs a C switch statement representing the string table."""
 
-  def Format(self, item, lang='en', begin_item=True, output_dir='.'):
+  def Format(self, item, lang='en', output_dir='.'):
+    """Format the start of the table."""
     assert isinstance(lang, types.StringTypes)
-    if begin_item:
-      return 'const char* GetString(int id) {\n  switch (id) {'
-    else:
-      return '\n    default:\n      return 0;\n  }\n}'
+    return 'const char* GetString(int id) {\n  switch (id) {'
+
+  def FormatEnd(self, item, lang='en', output_dir='.'):
+    """Format the end of the table."""
+    assert isinstance(lang, types.StringTypes)
+    return '\n    default:\n      return 0;\n  }\n}'
+
 
 def _HexToOct(match):
   "Return the octal form of the hex numbers"
   hex = match.group("hex")
   result = ""
   while len(hex):
     next_num = int(hex[2:4], 16)
     result += "\\" + '%03d' % int(oct(next_num), 10)
     hex = hex[4:]
   return match.group("escaped_backslashes") + result
 
+
 class Message(interface.ItemFormatter):
   """Writes out a single message as part of the switch."""
 
-  def Format(self, item, lang='en', begin_item=True, output_dir='.'):
+  def Format(self, item, lang='en', output_dir='.'):
+    """Format a single message."""
     from grit.node import message
-    if not begin_item:
-      return ''
-
     assert isinstance(lang, types.StringTypes)
     assert isinstance(item, message.MessageNode)
 
     message = item.ws_at_start + item.Translate(lang) + item.ws_at_end
     # output message with non-ascii chars escaped as octal numbers
     # C's grammar allows escaped hexadecimal numbers to be infinite,
     # but octal is always of the form \OOO
     message = message.encode('utf-8').encode('string_escape')
     # an escaped char is (\xHH)+ but only if the initial
     # backslash is not escaped.
     not_a_backslash = r"(^|[^\\])"  # beginning of line or a non-backslash char
     escaped_backslashes = not_a_backslash + r"(\\\\)*"
     hex_digits = r"((\\x)[0-9a-f]{2})+"
     two_digit_hex_num = re.compile(
       r"(?P<escaped_backslashes>%s)(?P<hex>%s)"
       % (escaped_backslashes, hex_digits))
     message = two_digit_hex_num.sub(_HexToOct, message)
     # unescape \ (convert \\ back to \)
     message = message.replace('\\\\', '\\')
     message = message.replace('"', '\\"')
     message = util.LINEBREAKS.sub(r'\\n', message)
 
     name_attr = item.GetTextualIds()[0]
 
     return '\n    case %s:\n      return "%s";' % (name_attr, message)