Split BrowserThread into public API and private implementation, step 1.

tools/sort-headers.py

Index: tools/sort-headers.py
diff --git a/tools/sort-headers.py b/tools/sort-headers.py
index e51343ca861c54405e8c673e2985d075ff0e6480..2a17fddd88e13aecdaac4f63d553c7c0ee0a7eda 100755
--- a/tools/sort-headers.py
+++ b/tools/sort-headers.py
@@ -10,10 +10,14 @@ Shows a diff and prompts for confirmation before doing the deed.
 
 import optparse
 import os
+import subprocess
 import sys
 import termios
 import tty
 
+# List of extensions whose headers this script knows how to sort.
+_SOURCE_EXTENSIONS = ('h', 'hh', 'hpp', 'c', 'cc', 'cpp', 'cxx', 'mm',)
+
 def YesNo(prompt):
   """Prompts with a yes/no question, returns True if yes."""
   print prompt,
@@ -71,36 +75,80 @@ def SortHeader(infile, outfile):
     outfile.write(line)
 
 
+def DiffAndConfirm(filename, should_confirm):
+  fixfilename = filename + '.new'
+  infile = open(filename, 'r')
+  outfile = open(fixfilename, 'w')
+  SortHeader(infile, outfile)
+  infile.close()
+  outfile.close()  # Important so the below diff gets the updated contents.
+
+  try:
+    diff = os.system('diff -u %s %s' % (filename, fixfilename))
+    if diff >> 8 == 0:  # Check exit code.
+      print '%s: no change' % filename
+      return
+
+    if not should_confirm or YesNo('Use new file (y/N)?'):
+      os.rename(fixfilename, filename)
+  finally:
+    try:
+      os.remove(fixfilename)
+    except OSError:
+      # If the file isn't there, we don't care.
+      pass
+
+
+def GitShell(args, ignore_return=False):
+  """A shell invocation suitable for communicating with git. Returns
+  output as list of lines, raises exception on error.
+  """
+  job = subprocess.Popen(args,
+                         shell=True,
+                         stdout=subprocess.PIPE,
+                         stderr=subprocess.STDOUT)
+  (out, err) = job.communicate()
+  if job.returncode != 0 and not ignore_return:
+    print out
+    raise Exception("Error %d running command %s" % (
+        job.returncode, args))
+  return out.split('\n')
+
+
+def FilenamesFromGit(branch_name):
+  lines = GitShell('git diff --stat=600,500 %s' % branch_name)
+  filenames = []
+  for line in lines:
+    line = line.lstrip()
+    # Avoid summary line, and files that have been deleted (no plus).
+    if line.find('|') != -1 and line.find('+') != -1:
+      filename = line.split()[0]
+      if filename:
+        filename = filename.rstrip()
+        ext = filename.rsplit('.')[-1]
+        if ext in _SOURCE_EXTENSIONS:
+          filenames.append(filename)
+  return filenames
+
+
 def main():
   parser = optparse.OptionParser(usage='%prog filename1 filename2 ...')
-  opts, args = parser.parse_args()
-
-  if len(args) < 1:
+  parser.add_option('-g', '--gitbranch', dest='git_branch',
+                    help='Get list of files as diff from git branch.')
+  parser.add_option('-q', '--quiet', action='store_false', default=True,
+                    dest='should_confirm',
+                    help='Turn off confirmation prompt.')
+  opts, filenames = parser.parse_args()
+
+  if len(filenames) < 1 and not opts.git_branch:
     parser.print_help()
     sys.exit(1)
 
-  for filename in args:
-    fixfilename = filename + '.new'
-    infile = open(filename, 'r')
-    outfile = open(fixfilename, 'w')
-    SortHeader(infile, outfile)
-    infile.close()
-    outfile.close()  # Important so the below diff gets the updated contents.
+  if opts.git_branch:
+    filenames = FilenamesFromGit(opts.git_branch)
 
-    try:
-      diff = os.system('diff -u %s %s' % (filename, fixfilename))
-      if diff >> 8 == 0:  # Check exit code.
-        print '%s: no change' % filename
-        continue
-
-      if YesNo('Use new file (y/N)?'):
-        os.rename(fixfilename, filename)
-    finally:
-      try:
-        os.remove(fixfilename)
-      except OSError:
-        # If the file isn't there, we don't care.
-        pass
+  for filename in filenames:
+    DiffAndConfirm(filename, opts.should_confirm)
 
 
 if __name__ == '__main__':