From fa99f36494550d967e115b3730d2ca4508f6f038 Mon Sep 17 00:00:00 2001
From: Bashikuro <juanjmeneses@gmail.com>
Date: Tue, 11 Oct 2016 02:43:36 -0500
Subject: [PATCH] Ignore paths from `.gitignore` (#147)

---
 options-manager.js                      | 23 ++++++++++++++++++++++-
 package.json                            |  1 +
 readme.md                               |  2 +-
 test/.gitignore                         |  2 ++
 test/bar/.gitignore                     |  1 +
 test/bar/foobar/.gitignore              |  1 +
 test/cli.js                             | 11 +++++++++++
 test/fixtures/gitignore/index.js        |  5 +++++
 test/fixtures/gitignore/test/.gitignore |  1 +
 test/fixtures/gitignore/test/bar.js     |  6 ++++++
 test/fixtures/gitignore/test/foo.js     |  6 ++++++
 test/options-manager.js                 | 18 ++++++++++++++++++
 12 files changed, 75 insertions(+), 2 deletions(-)
 create mode 100644 test/.gitignore
 create mode 100644 test/bar/.gitignore
 create mode 100644 test/bar/foobar/.gitignore
 create mode 100644 test/fixtures/gitignore/index.js
 create mode 100644 test/fixtures/gitignore/test/.gitignore
 create mode 100644 test/fixtures/gitignore/test/bar.js
 create mode 100644 test/fixtures/gitignore/test/foo.js

diff --git a/options-manager.js b/options-manager.js
index 8695c7b5..b6d242d7 100644
--- a/options-manager.js
+++ b/options-manager.js
@@ -7,6 +7,8 @@ const deepAssign = require('deep-assign');
 const multimatch = require('multimatch');
 const resolveFrom = require('resolve-from');
 const pathExists = require('path-exists');
+const parseGitignore = require('parse-gitignore');
+const globby = require('globby');
 
 const DEFAULT_IGNORE = [
 	'**/node_modules/**',
@@ -203,11 +205,29 @@ function groupConfigs(paths, baseOptions, overrides) {
 	return arr;
 }
 
+function getIgnores(opts) {
+	opts.ignores = DEFAULT_IGNORE.concat(opts.ignores || []);
+	const gitignores = globby.sync('**/.gitignore', {ignore: opts.ignores, cwd: opts.cwd || process.cwd()});
+	const ignores = gitignores
+	.map(pathToGitignore => {
+		const patterns = parseGitignore(pathToGitignore);
+		const base = path.dirname(pathToGitignore);
+
+		return patterns.map(file => path.join(base, file));
+	})
+	.reduce((a, b) => a.concat(b), []);
+
+	opts.ignores = opts.ignores.concat(ignores);
+
+	return opts;
+}
+
 function preprocess(opts) {
 	opts = mergeWithPkgConf(opts);
 	opts = normalizeOpts(opts);
-	opts.ignores = DEFAULT_IGNORE.concat(opts.ignores || []);
+	opts = getIgnores(opts);
 	opts.extensions = DEFAULT_EXTENSION.concat(opts.extensions || []);
+
 	return opts;
 }
 
@@ -221,3 +241,4 @@ exports.mergeApplicableOverrides = mergeApplicableOverrides;
 exports.groupConfigs = groupConfigs;
 exports.preprocess = preprocess;
 exports.emptyOptions = emptyOptions;
+exports.getIgnores = getIgnores;
diff --git a/package.json b/package.json
index ceea5f6b..d4f46a7e 100644
--- a/package.json
+++ b/package.json
@@ -77,6 +77,7 @@
     "has-flag": "^2.0.0",
     "meow": "^3.4.2",
     "multimatch": "^2.1.0",
+    "parse-gitignore": "^0.3.1",
     "path-exists": "^3.0.0",
     "pkg-conf": "^2.0.0",
     "resolve-cwd": "^1.0.0",
diff --git a/readme.md b/readme.md
index 50e9767d..eced4653 100644
--- a/readme.md
+++ b/readme.md
@@ -161,7 +161,7 @@ Additional global variables your code accesses during execution.
 
 Type: `Array`
 
-Some [paths](https://github.com/sindresorhus/xo/blob/master/options-manager.js) are ignored by default. Additional ignores can be added here.
+Some [paths](https://github.com/sindresorhus/xo/blob/master/options-manager.js) are ignored by default, including paths in .gitignore. Additional ignores can be added here.
 
 ### space
 
diff --git a/test/.gitignore b/test/.gitignore
new file mode 100644
index 00000000..c542df16
--- /dev/null
+++ b/test/.gitignore
@@ -0,0 +1,2 @@
+# This is a test .gitignore.
+foo/
diff --git a/test/bar/.gitignore b/test/bar/.gitignore
new file mode 100644
index 00000000..066381ba
--- /dev/null
+++ b/test/bar/.gitignore
@@ -0,0 +1 @@
+foo.js
\ No newline at end of file
diff --git a/test/bar/foobar/.gitignore b/test/bar/foobar/.gitignore
new file mode 100644
index 00000000..b80cafad
--- /dev/null
+++ b/test/bar/foobar/.gitignore
@@ -0,0 +1 @@
+bar.js
\ No newline at end of file
diff --git a/test/cli.js b/test/cli.js
index 48e1c497..0df64b72 100644
--- a/test/cli.js
+++ b/test/cli.js
@@ -31,6 +31,17 @@ test.failing('ignores fixture', async t => {
 	t.throws(execa('../../../cli.js', ['--no-local'], {cwd}));
 });
 
+test('ignore files in .gitignore', async t => {
+	const cwd = path.join(__dirname, 'fixtures/gitignore');
+
+	try {
+		await execa('../../../cli.js', ['--no-local'], {cwd});
+	} catch (err) {
+		t.is(err.stdout.indexOf('foo.js'), -1);
+		t.true(err.stdout.indexOf('bar.js') !== -1);
+	}
+});
+
 test('supports being extended with a shareable config', async () => {
 	const cwd = path.join(__dirname, 'fixtures/project');
 	await execa('../../../cli.js', ['--no-local'], {cwd});
diff --git a/test/fixtures/gitignore/index.js b/test/fixtures/gitignore/index.js
new file mode 100644
index 00000000..0a9af888
--- /dev/null
+++ b/test/fixtures/gitignore/index.js
@@ -0,0 +1,5 @@
+'use strict'
+
+module.exports = function (foo) {
+  return foo + 'bar'
+}
diff --git a/test/fixtures/gitignore/test/.gitignore b/test/fixtures/gitignore/test/.gitignore
new file mode 100644
index 00000000..066381ba
--- /dev/null
+++ b/test/fixtures/gitignore/test/.gitignore
@@ -0,0 +1 @@
+foo.js
\ No newline at end of file
diff --git a/test/fixtures/gitignore/test/bar.js b/test/fixtures/gitignore/test/bar.js
new file mode 100644
index 00000000..11c61b8a
--- /dev/null
+++ b/test/fixtures/gitignore/test/bar.js
@@ -0,0 +1,6 @@
+import test from 'ava'
+import fn from '../'
+
+test(t => {
+   t.is(fn('foo'), fn('foobar'))
+})
diff --git a/test/fixtures/gitignore/test/foo.js b/test/fixtures/gitignore/test/foo.js
new file mode 100644
index 00000000..bc98824b
--- /dev/null
+++ b/test/fixtures/gitignore/test/foo.js
@@ -0,0 +1,6 @@
+import test from 'ava'
+import fn from '../'
+
+test(t => {
+    t.is(fn('foo'), fn('foobar'))
+})
diff --git a/test/options-manager.js b/test/options-manager.js
index 3fff1a72..7f6b5cf4 100644
--- a/test/options-manager.js
+++ b/test/options-manager.js
@@ -142,6 +142,24 @@ test('groupConfigs', t => {
 	}));
 });
 
+test('gitignore', t => {
+	const result = manager.getIgnores({});
+	t.not(result.ignores.indexOf(path.join('foo', '**')), -1);
+	t.not(result.ignores.indexOf(path.join('bar', 'foo.js')), -1);
+});
+
+test('ignore ignored .gitignore', t => {
+	const opts = {
+		ignores: [
+			'**/foobar/**'
+		]
+	};
+
+	const result = manager.getIgnores(opts);
+
+	t.is(result.ignores.indexOf(path.join('bar', 'foobar', 'bar.js')), -1);
+});
+
 test('mergeWithPkgConf: use child if closest', t => {
 	const cwd = path.resolve('fixtures', 'nested', 'child');
 	const result = manager.mergeWithPkgConf({cwd});