Add support for iOS application bundle to GN.

build/config/ios/ios_gen_plist.py

Index: build/config/ios/ios_gen_plist.py
diff --git a/build/config/ios/ios_gen_plist.py b/build/config/ios/ios_gen_plist.py
new file mode 100644
index 0000000000000000000000000000000000000000..937c200a4a259cf1676bd32384cbb7e43686c02e
--- /dev/null
+++ b/build/config/ios/ios_gen_plist.py
@@ -0,0 +1,143 @@
+# Copyright 2016 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.
+
+import argparse
+import plistlib
+import os
+import re
+import subprocess
+import sys
+import tempfile
+import shlex
+
+
+# Xcode substitutes variables like ${PRODUCT_NAME} when compiling Info.plist.
+# It also supports supports modifiers like :identifier or :rfc1034identifier.
+# SUBST_RE matches a variable substitution pattern with an optional modifier,
+# while IDENT_RE matches all characters that are not valid in an "identifier"
+# value (used when applying the modifier).
+SUBST_RE = re.compile(r'\$\{(?P<id>[^}]*?)(?P<modifier>:[^}]*)?\}')
+IDENT_RE = re.compile(r'[/\s]')
+
+
+class ArgumentParser(argparse.ArgumentParser):
+  """Subclass of argparse.ArgumentParser to work with GN response files.
+
+  GN response file writes all the arguments on a single line and assumes
+  that the python script uses shlext.split() to extract them. Since the
+  default ArgumentParser expects a single argument per line, we need to
+  provide a subclass to have the correct support for @{{response_file_name}}.
+  """
+
+  def convert_arg_line_to_args(self, arg_line):
+    return shlex.split(arg_line)
+
+
+def Merge(plist1, plist2):
+  """Recursively merges |plist2| into |plist1|."""
+  if not plist1:
+    return plist2
+  for key in plist2:
+    value = plist2[key]
+    if isinstance(value, dict):
+      plist1[key] = Merge(plist1.get(key, {}), value)
+    else:
+      plist1[key] = value
+  return plist1
+
+
+def Interpolate(plist, substitutions):
+  """Interpolates ${variable} into |plist| using mapping in |substitutions|."""
+  result = []
+  groups = SUBST_RE.split(plistlib.writePlistToString(plist))
+  # SUBST_RE defines two patterns, so given a string, SUBST_RE.split will
+  # return a list whose position correspond to an unmatched fragment, a
+  # match identifier or a match modifier (may be None as it is optional).
+  # Enumerate over the value and check the index modulo 3 to figure out
+  # the category of the value.
+  for i, value in enumerate(groups):
+    if i % 3 == 0:
+      result.append(value)
+    elif i % 3 == 1:
+      if value in substitutions:
+        result.append(substitutions[value])
+      else:
+        result.append('${%s}' % value)
+    elif i % 3 == 2:
+      value, modifier = result[-1], value
+      # Apply the modifier if defined (otherwise the value will be None). At
+      # the beginning Xcode only supported :identifier that replaced all the
+      # characters that are invalid by an hyphen, however, this is an invalid
+      # character in a bundle identifier which is a reversed domain name and
+      # so :rfc1034identifier was created that instead uses an underscore.
+      if modifier == 'identifier':
+        value = IDENT_RE.sub('-', value)
+      elif modifier == 'rfc1034identifier':
+        value = IDENT_RE.sub('_', value)
+      result[-1] = value
+  return CleanPlist(plistlib.readPlistFromString(''.join(result)))
+
+
+def CleanPlist(plist):
+  """Removes all key of |plist| with unexpanded variables substitution."""
+  key_to_remove = []
+  for key in plist:
+    value = plist[key]
+    data = plistlib.writePlistToString(value)
+    if SUBST_RE.search(data):
+      key_to_remove.append(key)
+  for key in key_to_remove:
+    del plist[key]
+  return plist
+
+
+def LoadPList(path):
+  """Loads Plist at |path| and returns it as a dictionary."""
+  fd, name = tempfile.mkstemp()
+  try:
+    subprocess.check_call(['plutil', '-convert', 'xml1', '-o', name, path])
+    with os.fdopen(fd, 'r') as f:
+      return plistlib.readPlist(f)
+  finally:
+    os.unlink(name)
+
+
+def SavePList(path, data):
+  """Saves |data| as a Plist to |path| in binary1 format."""
+  fd, name = tempfile.mkstemp()
+  try:
+    with os.fdopen(fd, 'w') as f:
+      plistlib.writePlist(data, f)
+    subprocess.check_call(['plutil', '-convert', 'binary1', '-o', path, name])
+  finally:
+    os.unlink(name)
+
+
+def main():
+  parser = ArgumentParser(
+      description='A script to generate iOS application Info.plist.',
+      fromfile_prefix_chars='@')
+  parser.add_argument('-o', '--output', required=True,
+                      help='Path to output plist file.')
+  parser.add_argument('-s', '--subst', action='append', default=[],
+                      help='Substitution rule in the format "key=value".')
+  parser.add_argument('path', nargs="+", help='Path to input plist files.')
+  args = parser.parse_args()
+
+  substitutions = {}
+  for subst in args.subst:
+    key, value = subst.split('=', 1)
+    substitutions[key] = value
+
+  data = {}
+  for path in args.path:
+    data = Merge(data, LoadPList(path))
+
+  data = Interpolate(data, substitutions)
+  SavePList(args.output, data)
+  return 0
+
+
+if __name__ == '__main__':
+  sys.exit(main())