add index.js

index.js

@@ -0,0 +1,47 @@
+var fs          = require('fs');
+var Transform   = require('stream').Transform;
+var Vinyl       = require('vinyl');
+
+module.exports = function() {
+  return new Transform({
+    objectMode: true,
+
+    transform(file, enc, cb) {
+      var dir  = file.dirname;
+      var hash = file.contents.toString().trim();
+
+      var tags = fs.readdirSync(dir + '/refs/tags', 'utf8').reverse();
+      var ver  = '';
+
+      if (hash.slice(0, 5) === 'ref: ') {
+        hash = fs.readFileSync(dir + '/' + hash.slice(5).trim(), 'utf8').trim();
+      }
+
+      tags.some((tag, i) => {
+        var h = fs.readFileSync(dir + '/refs/tags/' + tag, 'utf8').trim();
+
+        if (h === hash) {
+          ver = tag;
+        }
+
+        return ver || i > 50;
+      });
+
+      this.push(
+        new Vinyl({
+          path: 'revision.txt',
+          contents: Buffer.from(hash),
+        })
+      );
+
+      this.push(
+        new Vinyl({
+          path: 'version.txt',
+          contents: Buffer.from(ver),
+        })
+      );
+
+      cb();
+    },
+  });
+};