🔨 changes

index.js

@@ -81,9 +81,9 @@ is.promise = x => {
 		);
 };
 
-is.generator = x => x && typeof x.next === 'function' && typeof x.throw === 'function';
+is.generator = x => is.iterable(x) && is.function(x.next) && is.function(x.throw);
 
-is.generatorFunction = x => x.constructor.name === 'GeneratorFunction';
+is.generatorFunction = x => getObjectType(x) === 'GeneratorFunction';
 
 is.regExp = x => getObjectType(x) === 'RegExp';
 is.date = x => getObjectType(x) === 'Date';

readme.md

@@ -79,6 +79,9 @@ Keep in mind that [functions are objects too](https://developer.mozilla.org/en-U
 Returns `true` for any object with a `.then()` and `.catch()` method. Prefer this one over `.nativePromise()` as you usually want to allow userland promise implementations too.
 
 ##### .generator(value)
+
+Returns `true` for any object that implements its own `.next()` and `.throw()` methods and has a function definition for `Symbol.iterator`.
+
 ##### .generatorFunction(value)
 
 ##### .map(value)

test.js

@@ -54,6 +54,9 @@ const types = new Map([
 		PromiseSubclassFixture.resolve()
 	]],
 	['promise', {then() {}, catch() {}}],
+	['generator', (function * () {
+		yield 42;
+	})()],
 	['map', new Map()],
 	['set', new Set()],
 	['weakMap', new WeakMap()],
@@ -167,10 +170,7 @@ if (isNode8orHigher) {
 }
 
 test('is.generator', t => {
-	const genObj = (function * () {
+	testType(t, 'generator', ['function']);
-		yield 42;
-	})();
-	t.true(m.generator(genObj));
 });
 
 test('is.generatorFunction', t => {