utils/lint/common_lint.py

   1 #!/usr/bin/python
   2 #
   3 # Common lint functions applicable to multiple types of files.
   4
   5 from __future__ import print_function
   6 import re
   7
   8 def VerifyLineLength(filename, lines, max_length):
   9   """Checks to make sure the file has no lines with lines exceeding the length
  10   limit.
  11
  12   Args:
  13     filename: the file under consideration as string
  14     lines: contents of the file as string array
  15     max_length: maximum acceptable line length as number
  16
  17   Returns:
  18     A list of tuples with format [(filename, line number, msg), ...] with any
  19     violations found.
  20   """
  21   lint = []
  22   line_num = 1
  23   for line in lines:
  24     length = len(line.rstrip('\n'))
  25     if length > max_length:
  26       lint.append((filename, line_num,
  27                    'Line exceeds %d chars (%d)' % (max_length, length)))
  28     line_num += 1
  29   return lint
  30
  31 def VerifyTabs(filename, lines):
  32   """Checks to make sure the file has no tab characters.
  33
  34   Args:
  35     filename: the file under consideration as string
  36     lines: contents of the file as string array
  37
  38   Returns:
  39     A list of tuples with format [(line_number, msg), ...] with any violations
  40     found.
  41   """
  42   lint = []
  43   tab_re = re.compile(r'\t')
  44   line_num = 1
  45   for line in lines:
  46     if tab_re.match(line.rstrip('\n')):
  47       lint.append((filename, line_num, 'Tab found instead of whitespace'))
  48     line_num += 1
  49   return lint
  50
  51
  52 def VerifyTrailingWhitespace(filename, lines):
  53   """Checks to make sure the file has no lines with trailing whitespace.
  54
  55   Args:
  56     filename: the file under consideration as string
  57     lines: contents of the file as string array
  58
  59   Returns:
  60     A list of tuples with format [(filename, line number, msg), ...] with any
  61     violations found.
  62   """
  63   lint = []
  64   trailing_whitespace_re = re.compile(r'\s+$')
  65   line_num = 1
  66   for line in lines:
  67     if trailing_whitespace_re.match(line.rstrip('\n')):
  68       lint.append((filename, line_num, 'Trailing whitespace'))
  69     line_num += 1
  70   return lint
  71
  72
  73 class BaseLint:
  74   def RunOnFile(filename, lines):
  75     raise Exception('RunOnFile() unimplemented')
  76
  77
  78 def RunLintOverAllFiles(linter, filenames):
  79   """Runs linter over the contents of all files.
  80
  81   Args:
  82     lint: subclass of BaseLint, implementing RunOnFile()
  83     filenames: list of all files whose contents will be linted
  84
  85   Returns:
  86     A list of tuples with format [(filename, line number, msg), ...] with any
  87     violations found.
  88   """
  89   lint = []
  90   for filename in filenames:
  91     file = open(filename, 'r')
  92     if not file:
  93       print('Cound not open %s' % filename)
  94       continue
  95     lines = file.readlines()
  96     lint.extend(linter.RunOnFile(filename, lines))
  97
  98   return lint