many-to-one 5/9: Generate codes.rs from registry.rs

# This commit was generated by running the following Python code:
# (followed by `sed -Ei 's/(mod registry;)/\1mod codes;/' crates/ruff/src/lib.rs`
# and `cargo fmt`).

import json
import re
import subprocess

def parse_registry():
    file = open('crates/ruff/src/registry.rs')

    rules = []

    while next(file) != 'ruff_macros::register_rules!(\n':
        continue

    while (line := next(file)) != ');\n':
        line = line.strip().rstrip(',')
        if line.startswith('//') or line.startswith('#['):
            rules.append(line)
            continue
        code, path = line.split(' => ')
        name = path.rsplit('::')[-1]
        rules.append((code, name))

    while (line := next(file)) != 'pub enum Linter {\n':
        continue

    prefixes = []
    prefix2linter = []

    while (line := next(file).strip()) != '}':
        if line.startswith('//'):
            continue
        if line.startswith('#[prefix = '):
            prefixes.append(line.split()[-1].strip('"]'))
        else:
            for prefix in prefixes:
                prefix2linter.append((prefix, line.rstrip(',')))
            prefixes.clear()

    prefix2linter.sort(key = lambda t: len(t[0]), reverse=True)

    return rules, prefix2linter

rules, prefix2linter = parse_registry()

def parse_code(code):
    prefix = re.match('[A-Z]+', code).group()
    if prefix in ('E', 'W'):
        return 'Pycodestyle', code

    for prefix, linter in prefix2linter:
        if code.startswith(prefix):
            return linter, code[len(prefix) :]

    assert False

text = '''
use crate::registry::{Linter, Rule};

pub fn code_to_rule(linter: Linter, code: &str) -> Option<Rule> {
    #[allow(clippy::enum_glob_use)]
    use Linter::*;

    Some(match (linter, code) {
'''

for entry in rules:
    if isinstance(entry, str):
        if entry.startswith('//'):
            text += '\n' + entry
        else:
            text += entry
    else:
        namespace, code = parse_code(entry[0])
        text += f'({namespace}, "{code}") => Rule::{entry[1]},'
    text += '\n'

text += '''
       _ => return  None,
    })
}
'''

with open('crates/ruff/src/codes.rs', 'w') as f:
    f.write(text)