grit: delay "help" builtin parsing

The "help" ad-hoc parsing only works in the simplest case:
  grit help
  grit help foo

When passing options to grit, the "help" builtin fails and producing
confusing output:
  $ grit -i ... help
  No such tool.  Try running 'grit help' for a list of tools.
  $ grit -i ... help xmb
  No such tool.  Try running 'grit help' for a list of tools.

Delay parsing of the "help" tool until after we've processed grit's
core options.

Bug: 747171
Change-Id: Iae5fdee2493346cee4272368ac8862647433faaf
Reviewed-on: https://chromium-review.googlesource.com/c/1320690Reviewed-by: agrieve <agrieve@chromium.org>
Commit-Queue: Mike Frysinger <vapier@chromium.org>
Cr-Commit-Position: refs/heads/master@{#605854}

tools/grit/grit/grit_runner.py

@@ -196,64 +196,65 @@ def Main(args):
   """Parses arguments and does the appropriate thing."""
   util.ChangeStdoutEncoding()
 
-  if not args or (len(args) == 1 and args[0] == 'help'):
-    PrintUsage()
-    return 0
-  elif len(args) == 2 and args[0] == 'help':
-    tool = args[1].lower()
-    if not _GetToolInfo(tool):
-      print "No such tool.  Try running 'grit help' for a list of tools."
-      return 2
-
-    print ("Help for 'grit %s' (for general help, run 'grit help'):\n"
-           % (tool))
-    print _GetToolInfo(tool)[_FACTORY]().__doc__
-    return 0
-  else:
-    options = Options()
-    try:
-      args = options.ReadOptions(args)  # args may be shorter after this
-    except getopt.GetoptError as e:
-      print "grit:", str(e)
-      print "Try running 'grit help' for valid options."
-      return 1
-    if not args:
-      print "No tool provided.  Try running 'grit help' for a list of tools."
-      return 2
-    tool = args[0]
-    if not _GetToolInfo(tool):
-      print "No such tool.  Try running 'grit help' for a list of tools."
-      return 2
-
-    try:
-      if _GetToolInfo(tool)[_REQUIRES_INPUT]:
-        os.stat(options.input)
-    except OSError:
-      print ('Input file %s not found.\n'
-             'To specify a different input file:\n'
-             '  1. Use the GRIT_INPUT environment variable.\n'
-             '  2. Use the -i command-line option.  This overrides '
-             'GRIT_INPUT.\n'
-             '  3. Specify neither GRIT_INPUT or -i and GRIT will try to load '
-             "'resource.grd'\n"
-             '     from the current directory.' % options.input)
-      return 2
-
-    if options.hash:
-      grit.extern.FP.UseUnsignedFingerPrintFromModule(options.hash)
-
-    try:
-      toolobject = _GetToolInfo(tool)[_FACTORY]()
-      if options.profile_dest:
-        import hotshot
-        prof = hotshot.Profile(options.profile_dest)
-        return prof.runcall(toolobject.Run, options, args[1:])
-      else:
-        return toolobject.Run(options, args[1:])
-    except getopt.GetoptError as e:
-      print "grit: %s: %s" % (tool, str(e))
-      print "Try running 'grit help %s' for valid options." % (tool,)
-      return 1
+  options = Options()
+  try:
+    args = options.ReadOptions(args)  # args may be shorter after this
+  except getopt.GetoptError as e:
+    print "grit:", str(e)
+    print "Try running 'grit help' for valid options."
+    return 1
+  if not args:
+    print "No tool provided.  Try running 'grit help' for a list of tools."
+    return 2
+
+  tool = args[0]
+  if tool == 'help':
+    if len(args) == 1:
+      PrintUsage()
+      return 0
+    else:
+      tool = args[1]
+      if not _GetToolInfo(tool):
+        print "No such tool.  Try running 'grit help' for a list of tools."
+        return 2
+
+      print ("Help for 'grit %s' (for general help, run 'grit help'):\n"
+             % (tool))
+      print _GetToolInfo(tool)[_FACTORY]().__doc__
+      return 0
+  if not _GetToolInfo(tool):
+    print "No such tool.  Try running 'grit help' for a list of tools."
+    return 2
+
+  try:
+    if _GetToolInfo(tool)[_REQUIRES_INPUT]:
+      os.stat(options.input)
+  except OSError:
+    print ('Input file %s not found.\n'
+           'To specify a different input file:\n'
+           '  1. Use the GRIT_INPUT environment variable.\n'
+           '  2. Use the -i command-line option.  This overrides '
+           'GRIT_INPUT.\n'
+           '  3. Specify neither GRIT_INPUT or -i and GRIT will try to load '
+           "'resource.grd'\n"
+           '     from the current directory.' % options.input)
+    return 2
+
+  if options.hash:
+    grit.extern.FP.UseUnsignedFingerPrintFromModule(options.hash)
+
+  try:
+    toolobject = _GetToolInfo(tool)[_FACTORY]()
+    if options.profile_dest:
+      import hotshot
+      prof = hotshot.Profile(options.profile_dest)
+      return prof.runcall(toolobject.Run, options, args[1:])
+    else:
+      return toolobject.Run(options, args[1:])
+  except getopt.GetoptError as e:
+    print "grit: %s: %s" % (tool, str(e))
+    print "Try running 'grit help %s' for valid options." % (tool,)
+    return 1
 
 
 if __name__ == '__main__':