feat: introduce Object.isPromise

Detect thenables
medikoo · May 15, 2017 · 27aecc8 · 27aecc8
1 parent 0cc6a7b
commit 27aecc8
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diff --git a/object/index.js b/object/index.js
@@ -29,6 +29,7 @@ module.exports = {
 	isNumberValue:              require('./is-number-value'),
 	isObject:                   require('./is-object'),
 	isPlainObject:              require('./is-plain-object'),
+	isPromise:                  require('./is-promise'),
 	isValue:                    require('./is-value'),
 	keyOf:                      require('./key-of'),
 	keys:                       require('./keys'),

diff --git a/object/is-promise.js b/object/is-promise.js
@@ -0,0 +1,6 @@
+'use strict';
+
+var isCallable = require('./is-callable')
+  , isObject   = require('./is-object');
+
+module.exports = function (value) { return isObject(value) && isCallable(value.then); };
diff --git a/test/object/is-promise.js b/test/object/is-promise.js
@@ -0,0 +1,17 @@
+"use strict";
+
+module.exports = function (t, a) {
+	var promise;
+	a(t(), false);
+	a(t(null), false);
+	a(t("promise"), false);
+	a(t({}), false);
+	a(t(function () {}), false);
+	a(t({ then: {} }), false);
+	a(t({ then: function () {} }), true);
+	promise = function () {};
+	promise.then = {};
+	a(t(promise), false);
+	promise.then = function () {};
+	a(t(promise), true);
+};