llvm/utils/relative_lines.py

   1 #!/usr/bin/env python3
   2
   3 """Replaces absolute line numbers in lit-tests with relative line numbers.
   4
   5 Writing line numbers like 152 in 'RUN: or CHECK:' makes tests hard to maintain:
   6 inserting lines in the middle of the test means updating all the line numbers.
   7
   8 Encoding them relative to the current line helps, and tools support it:
   9     Lit will substitute %(line+2) with the actual line number
  10     FileCheck supports [[@LINE+2]]
  11
  12 This tool takes a regex which captures a line number, and a list of test files.
  13 It searches for line numbers in the files and replaces them with a relative
  14 line number reference.
  15 """
  16
  17 USAGE = """Example usage:
  18     find -type f clang/test/CodeCompletion | grep -v /Inputs/ | \\
  19     xargs relative_lines.py --dry-run --verbose --near=100 \\
  20     --pattern='-code-completion-at[ =]%s:(\d+)' \\
  21     --pattern='requires fix-it: {(\d+):\d+-(\d+):\d+}'
  22 """
  23
  24 import argparse
  25 import re
  26 import sys
  27
  28 def b(x):
  29     return bytes(x, encoding='utf-8')
  30
  31 parser = argparse.ArgumentParser(prog = 'relative_lines',
  32                                  description = __doc__,
  33                                  epilog = USAGE,
  34                                  formatter_class=argparse.RawTextHelpFormatter)
  35 parser.add_argument('--near', type=int, default=20,
  36                     help = "maximum line distance to make relative")
  37 parser.add_argument('--partial', action='store_true', default=False,
  38                     help = "apply replacements to files even if others failed")
  39 parser.add_argument('--pattern', default=[], action='append',
  40                     type=lambda x: re.compile(b(x)),
  41                     help = "regex to match, with line numbers captured in ().")
  42 parser.add_argument('--verbose', action='store_true', default=False,
  43                     help = "print matches applied")
  44 parser.add_argument('--dry-run', action='store_true', default=False,
  45                     help = "don't apply replacements. Best with --verbose.")
  46 parser.add_argument('files', nargs = '+')
  47 args = parser.parse_args()
  48
  49 for file in args.files:
  50     try:
  51         contents = open(file, 'rb').read()
  52     except UnicodeDecodeError as e:
  53         print(f"{file}: not valid UTF-8 - {e}", file=sys.stderr)
  54     failures = 0
  55
  56     def line_number(offset):
  57         return 1 + contents[:offset].count(b'\n')
  58
  59     def replace_one(capture, line, offset):
  60         """Text to replace a capture group, e.g. 42 => %(line+1)"""
  61         try:
  62             target = int(capture)
  63         except ValueError:
  64             print(f"{file}:{line}: matched non-number '{capture}'", file=sys.stderr)
  65             return capture
  66
  67         if args.near > 0 and abs(target - line) > args.near:
  68             print(f"{file}:{line}: target line {target} is farther than {args.near}", file=sys.stderr)
  69             return capture
  70         if target > line:
  71             delta = '+' + str(target - line)
  72         elif target < line:
  73             delta = '-' + str(line - target)
  74         else:
  75             delta = ''
  76
  77         prefix = contents[:offset].rsplit(b'\n')[-1]
  78         is_lit = b'RUN' in prefix or b'DEFINE' in prefix
  79         text = ('%(line{0})' if is_lit else '[[@LINE{0}]]').format(delta)
  80         if args.verbose:
  81             print(f"{file}:{line}: {0} ==> {text}")
  82         return b(text)
  83
  84     def replace_match(m):
  85         """Text to replace a whole match, e.g. --at=42:3 => --at=%(line+2):3"""
  86         line = 1 + contents[:m.start()].count(b'\n')
  87         result = b''
  88         pos = m.start()
  89         for index, capture in enumerate(m.groups()):
  90             index += 1 # re groups are conventionally 1-indexed
  91             result += contents[pos:m.start(index)]
  92             replacement = replace_one(capture, line, m.start(index))
  93             result += replacement
  94             if replacement == capture:
  95                 global failures
  96                 failures += 1
  97             pos = m.end(index)
  98         result += contents[pos:m.end()]
  99         return result
 100
 101     for pattern in args.pattern:
 102         contents = re.sub(pattern, replace_match, contents)
 103     if failures > 0 and not args.partial:
 104         print(f"{file}: leaving unchanged (some failed, --partial not given)")
 105         continue
 106     if not args.dry_run:
 107         open(file, "wb").write(contents)