rust/util/lintlib.py

# Copyright 2014-2018 The Rust Project Developers. See the COPYRIGHT
# file at the top-level directory of this distribution and at
# http://rust-lang.org/COPYRIGHT.
#
# Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
# http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
# <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
# option. This file may not be copied, modified, or distributed
# except according to those terms.

# Common utils for the several housekeeping scripts.

import os
import re
import collections

import logging as log
log.basicConfig(level=log.INFO, format='%(levelname)s: %(message)s')

Lint = collections.namedtuple('Lint', 'name level doc sourcefile group')
Config = collections.namedtuple('Config', 'name ty doc default')

lintname_re = re.compile(r'''pub\s+([A-Z_][A-Z_0-9]*)''')
group_re = re.compile(r'''\s*([a-z_][a-z_0-9]+)''')
conf_re = re.compile(r'''define_Conf! {\n([^}]*)\n}''', re.MULTILINE)
confvar_re = re.compile(
    r'''/// Lint: (\w+). (.*).*\n\s*\([^,]+,\s+"([^"]+)",\s+([^=\)]+)=>\s+(.*)\),''', re.MULTILINE)

lint_levels = {
    "correctness": 'Deny',
    "style": 'Warn',
    "complexity": 'Warn',
    "perf": 'Warn',
    "restriction": 'Allow',
    "pedantic": 'Allow',
    "nursery": 'Allow',
    "cargo": 'Allow',
}


def parse_lints(lints, filepath):
    last_comment = []
    comment = True
    clippy = False
    deprecated = False
    name = ""

    with open(filepath) as fp:
        for line in fp:
            if comment:
                if line.startswith("/// "):
                    last_comment.append(line[4:])
                elif line.startswith("///"):
                    last_comment.append(line[3:])
                elif line.startswith("declare_lint!"):
                    import sys
                    print("don't use `declare_lint!` in Clippy, use `declare_clippy_lint!` instead")
                    sys.exit(42)
                elif line.startswith("declare_clippy_lint!"):
                    comment = False
                    deprecated = False
                    clippy = True
                    name = ""
                elif line.startswith("declare_deprecated_lint!"):
                    comment = False
                    deprecated = True
                    clippy = False
                else:
                    last_comment = []
            if not comment:
                m = lintname_re.search(line)

                if m:
                    name = m.group(1).lower()
                    line = next(fp)

                    if deprecated:
                        level = "Deprecated"
                        group = "deprecated"
                    else:
                        while True:
                            g = group_re.search(line)
                            if g:
                                group = g.group(1).lower()
                                level = lint_levels.get(group, None)
                                break
                            line = next(fp)

                    if level is None:
                        continue

                    log.info("found %s with level %s in %s",
                             name, level, filepath)
                    lints.append(Lint(name, level, last_comment, filepath, group))
                    last_comment = []
                    comment = True

                    if "}" in line:
                        log.warn("Warning: missing Lint-Name in %s", filepath)
                        comment = True


def parse_configs(path):
    configs = {}
    with open(os.path.join(path, 'utils/conf.rs')) as fp:
        contents = fp.read()

    match = re.search(conf_re, contents)
    confvars = re.findall(confvar_re, match.group(1))

    for (lint, doc, name, default, ty) in confvars:
        configs[lint.lower()] = Config(name.replace("_", "-"), ty, doc, default)

    return configs


def parse_all(path="clippy_lints/src"):
    lints = []
    for root, dirs, files in os.walk(path):
        for fn in files:
            if fn.endswith('.rs'):
                parse_lints(lints, os.path.join(root, fn))

    log.info("got %s lints", len(lints))

    configs = parse_configs(path)
    log.info("got %d configs", len(configs))

    return lints, configs