--- /dev/null
+'use strict';
+const fs = require('fs');
+const path = require('path');
+const glob = require('glob');
+const gitIgnore = require('ignore');
+const pify = require('pify');
+const slash = require('slash');
+
+const globP = pify(glob);
+const readFileP = pify(fs.readFile);
+
+const mapGitIgnorePatternTo = base => ignore => {
+ if (ignore.startsWith('!')) {
+ return '!' + path.posix.join(base, ignore.substr(1));
+ }
+
+ return path.posix.join(base, ignore);
+};
+
+const parseGitIgnore = (content, opts) => {
+ const base = slash(path.relative(opts.cwd, path.dirname(opts.fileName)));
+
+ return content
+ .split(/\r?\n/)
+ .filter(Boolean)
+ .filter(l => l.charAt(0) !== '#')
+ .map(mapGitIgnorePatternTo(base));
+};
+
+const reduceIgnore = files => {
+ return files.reduce((ignores, file) => {
+ ignores.add(parseGitIgnore(file.content, {
+ cwd: file.cwd,
+ fileName: file.filePath
+ }));
+ return ignores;
+ }, gitIgnore());
+};
+
+const getIsIgnoredPredecate = (ignores, cwd) => {
+ return p => ignores.ignores(slash(path.relative(cwd, p)));
+};
+
+const getFile = (file, cwd) => {
+ const filePath = path.join(cwd, file);
+ return readFileP(filePath, 'utf8')
+ .then(content => ({
+ content,
+ cwd,
+ filePath
+ }));
+};
+
+const getFileSync = (file, cwd) => {
+ const filePath = path.join(cwd, file);
+ const content = fs.readFileSync(filePath, 'utf8');
+
+ return {
+ content,
+ cwd,
+ filePath
+ };
+};
+
+const normalizeOpts = opts => {
+ opts = opts || {};
+ const ignore = opts.ignore || [];
+ const cwd = opts.cwd || process.cwd();
+ return {ignore, cwd};
+};
+
+module.exports = o => {
+ const opts = normalizeOpts(o);
+
+ return globP('**/.gitignore', {ignore: opts.ignore, cwd: opts.cwd})
+ .then(paths => Promise.all(paths.map(file => getFile(file, opts.cwd))))
+ .then(files => reduceIgnore(files))
+ .then(ignores => getIsIgnoredPredecate(ignores, opts.cwd));
+};
+
+module.exports.sync = o => {
+ const opts = normalizeOpts(o);
+
+ const paths = glob.sync('**/.gitignore', {ignore: opts.ignore, cwd: opts.cwd});
+ const files = paths.map(file => getFileSync(file, opts.cwd));
+ const ignores = reduceIgnore(files);
+ return getIsIgnoredPredecate(ignores, opts.cwd);
+};