Merge pull request sinonjs#1543 from alex94puchades/master

Add support to instanceOf for [Symbol.hasInstance]
fatso83 · Aug 27, 2017 · 15d5737 · 15d5737
2 parents c419543 + d035dea
commit 15d5737
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Showing 2 changed files with 20 additions and 2 deletions.
diff --git a/lib/sinon/match.js b/lib/sinon/match.js
@@ -17,6 +17,12 @@ function assertType(value, type, name) {
     }
 }
 
+function assertMethodExists(value, method, name, methodPath) {
+    if (value[method] == null) {
+        throw new TypeError("Expected " + name + " to have method " + methodPath);
+    }
+}
+
 var matcher = {
     toString: function () {
         return this.message;
@@ -179,10 +185,14 @@ match.typeOf = function (type) {
 };
 
 match.instanceOf = function (type) {
-    assertType(type, "function", "type");
+    if (typeof Symbol === "undefined" || typeof Symbol.hasInstance === "undefined") {
+        assertType(type, "function", "type");
+    } else {
+        assertMethodExists(type, Symbol.hasInstance, "type", "[Symbol.hasInstance]");
+    }
     return match(function (actual) {
         return actual instanceof type;
-    }, "instanceOf(" + functionName(type) + ")");
+    }, "instanceOf(" + (functionName(type) || Object.prototype.toString.call(type)) + ")");
 };
 
 function createPropertyMatcher(propertyTest, messagePrefix) {

diff --git a/test/match-test.js b/test/match-test.js
@@ -493,6 +493,14 @@ describe("sinonMatch", function () {
             }, "TypeError");
         });
 
+        if (typeof Symbol !== "undefined" && typeof Symbol.hasInstance !== "undefined") {
+            it("does not throw if given argument defines Symbol.hasInstance", function () {
+                var objectWithCustomTypeChecks = {};
+                objectWithCustomTypeChecks[Symbol.hasInstance] = function () {};
+                sinonMatch.instanceOf(objectWithCustomTypeChecks);
+            });
+        }
+
         it("returns matcher", function () {
             var instanceOf = sinonMatch.instanceOf(function () {});