xref: /openbsd-src/gnu/llvm/llvm/utils/relative_lines.py (revision d415bd752c734aee168c4ee86ff32e8cc249eb16)
1#!/usr/bin/env python3
2
3"""Replaces absolute line numbers in lit-tests with relative line numbers.
4
5Writing line numbers like 152 in 'RUN: or CHECK:' makes tests hard to maintain:
6inserting lines in the middle of the test means updating all the line numbers.
7
8Encoding 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
12This tool takes a regex which captures a line number, and a list of test files.
13It searches for line numbers in the files and replaces them with a relative
14line number reference.
15"""
16
17USAGE = """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
24import argparse
25import re
26import sys
27
28def b(x):
29    return bytes(x, encoding='utf-8')
30
31parser = argparse.ArgumentParser(prog = 'relative_lines',
32                                 description = __doc__,
33                                 epilog = USAGE,
34                                 formatter_class=argparse.RawTextHelpFormatter)
35parser.add_argument('--near', type=int, default=20,
36                    help = "maximum line distance to make relative")
37parser.add_argument('--partial', action='store_true', default=False,
38                    help = "apply replacements to files even if others failed")
39parser.add_argument('--pattern', default=[], action='append',
40                    type=lambda x: re.compile(b(x)),
41                    help = "regex to match, with line numbers captured in ().")
42parser.add_argument('--verbose', action='store_true', default=False,
43                    help = "print matches applied")
44parser.add_argument('--dry-run', action='store_true', default=False,
45                    help = "don't apply replacements. Best with --verbose.")
46parser.add_argument('files', nargs = '+')
47args = parser.parse_args()
48
49for 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)
108