tools/torque/format-torque.py

#!/usr/bin/env python
# Copyright 2014 the V8 project authors. All rights reserved.
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.

"""This program either generates the parser files for Torque, generating
the source and header files directly in V8's src directory."""

import subprocess
import sys
import re
from subprocess import Popen, PIPE

def preprocess(input):
  input = re.sub(r'(if\s+)constexpr(\s*\()', r'\1/*COxp*/\2', input)
  input = re.sub(r'(\s+)operator\s*(\'[^\']+\')', r'\1/*_OPE \2*/', input)

  # Mangle typeswitches to look like switch statements with the extra type
  # information and syntax encoded in comments.
  input = re.sub(r'(\s+)typeswitch\s*\(', r'\1/*_TYPE*/switch (', input)
  input = re.sub(r'(\s+)case\s*\(\s*([^\:]+)\s*\)(\s*)\:\s*deferred',
      r'\1case \2: /*_TSXDEFERRED_*/', input)
  input = re.sub(r'(\s+)case\s*\(\s*([^\:]+)\s*\)(\s*)\:',
      r'\1case \2: /*_TSX*/', input)
  input = re.sub(r'(\s+)case\s*\(\s*([^\s]+)\s*\:\s*([^\:]+)\s*\)(\s*)\:\s*deferred',
      r'\1case \3: /*_TSVDEFERRED_\2:*/', input)
  input = re.sub(r'(\s+)case\s*\(\s*([^\s]+)\s*\:\s*([^\:]+)\s*\)(\s*)\:',
      r'\1case \3: /*_TSV\2:*/', input)

  # Add extra space around | operators to fix union types later.
  while True:
    old = input
    input = re.sub(r'(\w+\s*)\|(\s*\w+)',
        r'\1|/**/\2', input)
    if old == input:
      break;

  input = re.sub(r'\sgenerates\s+\'([^\']+)\'\s*',
      r' _GeNeRaTeS00_/*\1@*/', input)
  input = re.sub(r'\sconstexpr\s+\'([^\']+)\'\s*',
      r' _CoNsExP_/*\1@*/', input)
  input = re.sub(r'\notherwise',
      r'\n otherwise', input)
  input = re.sub(r'(\n\s*\S[^\n]*\s)otherwise',
      r'\1_OtheSaLi', input)
  return input

def postprocess(output):
  output = re.sub(r'\/\*COxp\*\/', r'constexpr', output)
  output = re.sub(r'(\S+)\s*: type([,>])', r'\1: type\2', output)
  output = re.sub(r'(\n\s*)labels( [A-Z])', r'\1    labels\2', output)
  output = re.sub(r'\/\*_OPE \'([^\']+)\'\*\/', r"operator '\1'", output)
  output = re.sub(r'\/\*_TYPE\*\/(\s*)switch', r'typeswitch', output)
  output = re.sub(r'case (\w+)\:\s*\/\*_TSXDEFERRED_\*\/',
      r'case (\1): deferred', output)
  output = re.sub(r'case (\w+)\:\s*\/\*_TSX\*\/',
      r'case (\1):', output)
  output = re.sub(r'case (\w+)\:\s*\/\*_TSVDEFERRED_([^\:]+)\:\*\/',
      r'case (\2: \1): deferred', output)
  output = re.sub(r'case (\w+)\:\s*\/\*_TSV([^\:]+)\:\*\/',
      r'case (\2: \1):', output)
  output = re.sub(r'\n_GeNeRaTeS00_\s*\/\*([^@]+)@\*\/',
      r"\n    generates '\1'", output)
  output = re.sub(r'_GeNeRaTeS00_\s*\/\*([^@]+)@\*\/',
      r"generates '\1'", output)
  output = re.sub(r'_CoNsExP_\s*\/\*([^@]+)@\*\/',
      r"constexpr '\1'", output)
  output = re.sub(r'\n(\s+)otherwise',
      r"\n\1    otherwise", output)
  output = re.sub(r'\n(\s+)_OtheSaLi',
      r"\n\1otherwise", output)
  output = re.sub(r'_OtheSaLi',
      r"otherwise", output)

  while True:
    old = output
    output = re.sub(r'(\w+)\s{0,1}\|\s{0,1}/\*\*/(\s*\w+)',
        r'\1 |\2', output)
    if old == output:
      break;

  return output

if len(sys.argv) < 2 or len(sys.argv) > 3:
  print "invalid number of arguments"
  sys.exit(-1)

use_stdout = True
lint = False
if len(sys.argv) == 3:
  if sys.argv[1] == '-i':
    use_stdout = False
  if sys.argv[1] == '-l':
    lint = True

filename = sys.argv[len(sys.argv) - 1]

with open(filename, 'r') as content_file:
  content = content_file.read()
original_input = content
p = Popen(['clang-format', '-assume-filename=.ts'], stdin=PIPE, stdout=PIPE, stderr=PIPE)
output, err = p.communicate(preprocess(content))
output = postprocess(output)
rc = p.returncode
if (rc <> 0):
  sys.exit(rc);
if lint:
  if (output != original_input):
    print >>sys.stderr, filename + ' requires formatting'
elif use_stdout:
  print output
else:
  output_file = open(filename, 'w')
  output_file.write(output);
  output_file.close()