1 files changed, 19 insertions, 0 deletions
diff --git a/lib/internal/promiseCallback.js b/lib/internal/promiseCallback.js
new file mode 100644
index 0000000..685dd7a
--- /dev/null
+++ b/lib/internal/promiseCallback.js
@@ -0,0 +1,19 @@
+const PROMISE_SYMBOL = Symbol('promiseCallback')
+
+function promiseCallback () {
+    let resolve, reject
+    function callback (err, ...args) {
+        if (err) return reject(err)
+        resolve(args.length > 1 ? args : args[0])
+    }
+
+    callback[PROMISE_SYMBOL] = new Promise((res, rej) => {
+        resolve = res,
+        reject = rej
+    })
+
+    return callback
+}
+
+
+export { promiseCallback, PROMISE_SYMBOL }