MatchersUtil#contains uses deep equality rather than === for set members

[#169001712]

src/core/base.js

@@ -161,6 +161,10 @@ getJasmineRequireObj().base = function(j$, jasmineGlobal) {
     );
   };
 
+  j$.isIterable_ = function(value) {
+    return value && !!value[Symbol.iterator];
+  };
+
   j$.isDataView = function(obj) {
     return (
       obj !== null &&

src/core/matchers/matchersUtil.js

@@ -32,23 +32,45 @@ getJasmineRequireObj().MatchersUtil = function(j$) {
    * @returns {boolean} True if `needle` was found in `haystack`
    */
   MatchersUtil.prototype.contains = function(haystack, needle) {
-    if (j$.isSet(haystack)) {
-      return haystack.has(needle);
+    if (!haystack) {
+      return false;
     }
 
-    if (
-      Object.prototype.toString.apply(haystack) === '[object Array]' ||
-      (!!haystack && !haystack.indexOf)
-    ) {
+    if (j$.isSet(haystack)) {
+      // Try .has() first. It should be faster in cases where
+      // needle === something in haystack. Fall back to .equals() comparison
+      // if that fails.
+      if (haystack.has(needle)) {
+        return true;
+      }
+    }
+
+    if (j$.isIterable_(haystack) && !j$.isString_(haystack)) {
+      // Arrays, Sets, etc.
+      for (const candidate of haystack) {
+        if (this.equals(candidate, needle)) {
+          return true;
+        }
+      }
+
+      return false;
+    }
+
+    if (haystack.indexOf) {
+      // Mainly strings
+      return haystack.indexOf(needle) >= 0;
+    }
+
+    if (j$.isNumber_(haystack.length)) {
+      // Objects that are shaped like arrays but aren't iterable
       for (var i = 0; i < haystack.length; i++) {
         if (this.equals(haystack[i], needle)) {
           return true;
         }
       }
-      return false;
     }
 
-    return !!haystack && haystack.indexOf(needle) >= 0;
+    return false;
   };
 
   MatchersUtil.prototype.buildFailureMessage = function() {