use git index in hygiene

build/gulpfile.hygiene.js

@@ -12,9 +12,11 @@ const gulptslint = require('gulp-tslint');
 const gulpeslint = require('gulp-eslint');
 const tsfmt = require('typescript-formatter');
 const tslint = require('tslint');
+const VinylFile = require('vinyl');
 const vfs = require('vinyl-fs');
 const path = require('path');
 const fs = require('fs');
+const pall = require('p-all');
 
 /**
  * Hygiene works by creating cascading subsets of all our files and
@@ -157,7 +159,7 @@ gulp.task('tslint', () => {
 		.pipe(gulptslint.default.report(options));
 });
 
-const hygiene = exports.hygiene = (some, options) => {
+function hygiene(some, options) {
 	options = options || {};
 	let errorCount = 0;
 
@@ -279,7 +281,15 @@ const hygiene = exports.hygiene = (some, options) => {
 		this.emit('data', file);
 	});
 
-	const result = vfs.src(some || all, { base: '.', follow: true, allowEmpty: true })
+	let input;
+
+	if (Array.isArray(some) || typeof some === 'string' || !some) {
+		input = vfs.src(some || all, { base: '.', follow: true, allowEmpty: true });
+	} else {
+		input = some;
+	}
+
+	const result = input
 		.pipe(filter(f => !f.stat.isDirectory()))
 		.pipe(filter(eolFilter))
 		.pipe(options.skipEOL ? es.through() : eol)
@@ -331,9 +341,39 @@ const hygiene = exports.hygiene = (some, options) => {
 				this.emit('end');
 			}
 		}));
-};
+}
+
+function createGitIndexVinyls(paths) {
+	const cp = require('child_process');
+	const repositoryPath = process.cwd();
+
+	const fns = paths.map(relativePath => () => new Promise((c, e) => {
+		const fullPath = path.join(repositoryPath, relativePath);
+
+		fs.stat(fullPath, (err, stat) => {
+			if (err) {
+				return e(err);
+			}
+
+			cp.exec(`git show :${relativePath}`, { maxBuffer: 2000 * 1024, encoding: 'buffer' }, (err, out) => {
+				if (err) {
+					return e(err);
+				}
+
+				c(new VinylFile({
+					path: fullPath,
+					base: repositoryPath,
+					contents: out,
+					stat
+				}));
+			});
+		});
+	}));
+
+	return pall(fns, { concurrency: 4 });
+}
 
-gulp.task('hygiene', () => hygiene(''));
+gulp.task('hygiene', () => hygiene());
 
 // this allows us to run hygiene as a git pre-commit hook
 if (require.main === module) {
@@ -360,6 +400,7 @@ if (require.main === module) {
 				console.error();
 				console.error(err);
 				process.exit(1);
+				return;
 			}
 
 			const some = out
@@ -367,11 +408,17 @@ if (require.main === module) {
 				.filter(l => !!l);
 
 			if (some.length > 0) {
-				hygiene(some, { skipEOL: skipEOL }).on('error', err => {
-					console.error();
-					console.error(err);
-					process.exit(1);
-				});
+				console.log('Reading git index versions...');
+
+				createGitIndexVinyls(some)
+					.then(vinyls => new Promise((c, e) => hygiene(es.readArray(vinyls), { skipEOL: skipEOL })
+						.on('end', () => c())
+						.on('error', e)))
+					.catch(err => {
+						console.error();
+						console.error(err);
+						process.exit(1);
+					});
 			}
 		});
 	});

package.json

@@ -104,6 +104,7 @@
     "mocha": "^2.2.5",
     "object-assign": "^4.0.1",
     "optimist": "0.3.5",
+    "p-all": "^1.0.0",
     "pump": "^1.0.1",
     "queue": "3.0.6",
     "remap-istanbul": "^0.6.4",

yarn.lock

@@ -4160,6 +4160,12 @@ osenv@^0.1.3:
     os-homedir "^1.0.0"
     os-tmpdir "^1.0.0"
 
+p-all@^1.0.0:
+  version "1.0.0"
+  resolved "https://registry.yarnpkg.com/p-all/-/p-all-1.0.0.tgz#93bdf53a55a23821fdfa98b4174a99bf7f31df8d"
+  dependencies:
+    p-map "^1.0.0"
+
 p-finally@^1.0.0:
   version "1.0.0"
   resolved "https://registry.yarnpkg.com/p-finally/-/p-finally-1.0.0.tgz#3fbcfb15b899a44123b34b6dcc18b724336a2cae"
@@ -4176,6 +4182,10 @@ p-locate@^2.0.0:
   dependencies:
     p-limit "^1.1.0"
 
+p-map@^1.0.0:
+  version "1.2.0"
+  resolved "https://registry.yarnpkg.com/p-map/-/p-map-1.2.0.tgz#e4e94f311eabbc8633a1e79908165fca26241b6b"
+
 p-try@^1.0.0:
   version "1.0.0"
   resolved "https://registry.yarnpkg.com/p-try/-/p-try-1.0.0.tgz#cbc79cdbaf8fd4228e13f621f2b1a237c1b207b3"