Merge pull request #436 from Chalarangelo/isPromise

[FEATURE] Add isPromise snippet

snippets/isPromiseLike.md

@@ -0,0 +1,16 @@
+### isPromiseLike
+
+Returns `true` if an object looks like a [`Promise`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Promise), `false` otherwise.
+
+Check if the object is not `null`, its `typeof` matches either `object` or `function` and if it has a `.then` property, which is also a `function`.
+
+```js
+const isPromiseLike = obj =>
+  obj !== null && (typeof obj === 'object' || typeof obj === 'function') && typeof obj.then === 'function';
+```
+
+```js
+isPromiseLike({then:function () {return ''}}); // true
+isPromiseLike(null); // false
+isPromiseLike({}); // false
+```

tag_database

@@ -75,6 +75,7 @@ isFunction:utility
 isNull:utility
 isNumber:utility
 isPrime:math
+isPromiseLike:utility
 isString:utility
 isSymbol:utility
 isValidJSON:utility