debt-collector/dist/lib/fileSystem/getGitIgnoreFilter.js

a nodejs tool to identify, track and mesure technical debt

import fs from 'fs';
import path from 'path';
import { execSync } from 'child_process';
import ignore from 'ignore';
const getGitRootDir = () => {
    try {
        return execSync('git rev-parse --show-toplevel', {
            encoding: 'utf-8',
        }).trim();
    }
    catch {
        return null;
    }
};
// Cached per cwd — the .gitignore doesn't change during a single run.
const cache = new Map();
/** Clears the memoization cache. Exposed for testing only. */
export const clearGitIgnoreFilterCache = () => cache.clear();
/**
 * Reads .gitignore from the git repository root and returns
 * an `ignore` instance that can test file paths.
 * Returns `null` if not in a git repo or no .gitignore is found.
 *
 * Result is memoized per working directory to avoid repeated
 * `git rev-parse` subprocess calls (notably during `walk` iterations).
 */
export const getGitIgnoreFilter = () => {
    const cwd = process.cwd();
    if (cache.has(cwd))
        return cache.get(cwd);
    const gitRoot = getGitRootDir();
    if (!gitRoot) {
        cache.set(cwd, null);
        return null;
    }
    try {
        const content = fs.readFileSync(path.join(gitRoot, '.gitignore'), 'utf-8');
        const filter = ignore().add(content);
        cache.set(cwd, filter);
        return filter;
    }
    catch {
        cache.set(cwd, null);
        return null;
    }
};