Upload Kmake

test/common/countdown.js

@@ -0,0 +1,28 @@
+'use strict';
+
+const assert = require('assert');
+const kLimit = Symbol('limit');
+const kCallback = Symbol('callback');
+const common = require('./');
+
+class Countdown {
+  constructor(limit, cb) {
+    assert.strictEqual(typeof limit, 'number');
+    assert.strictEqual(typeof cb, 'function');
+    this[kLimit] = limit;
+    this[kCallback] = common.mustCall(cb);
+  }
+
+  dec() {
+    assert(this[kLimit] > 0, 'Countdown expired');
+    if (--this[kLimit] === 0)
+      this[kCallback]();
+    return this[kLimit];
+  }
+
+  get remaining() {
+    return this[kLimit];
+  }
+}
+
+module.exports = Countdown;