Implements fix and tests for Map equality. Adds test for array equality requiring order.

Author: Charlie Saunders

index.js

@@ -59,6 +59,14 @@ function isBuffer(x) {
   return true;
 }
 
+function arraysMatch(first, second) {
+  var i;
+  for (i = first.length - 1; i >= 0; i--) {
+    if (first[i] != second[i]) return false;
+  }
+  return true;
+}
+
 function objEquiv(a, b, opts) {
   /* eslint max-statements: [2, 40] */
   var i, key;
@@ -109,11 +117,8 @@ function objEquiv(a, b, opts) {
   ka.sort();
   kb.sort();
   // ~~~cheap key test
-  for (i = ka.length - 1; i >= 0; i--) {
-    if (ka[i] != kb[i]) {
-      return false;
-    }
-  }
+  if (!arraysMatch(ka, kb)) return false;
+
   // equivalent values for every corresponding key, and ~~~possibly expensive deep test
   for (i = ka.length - 1; i >= 0; i--) {
     key = ka[i];
@@ -122,6 +127,24 @@ function objEquiv(a, b, opts) {
     }
   }
 
+  // Maps
+  if (typeof Map && a.constructor === Map && b.constructor === Map) {
+    ka = Array.from(a.keys());
+    kb = Array.from(b.keys());
+
+    if (ka.length !== kb.length) return false;
+
+    ka.sort();
+    kb.sort();
+
+    if (!arraysMatch(ka, kb)) return false;
+
+    for (i = ka.length - 1; i >= 0; i--) {
+      key = ka[i];
+      if (!deepEqual(a.get(key), b.get(key), opts)) return false;
+    }
+  }
+
   return true;
 }
 

test/cmp.js

@@ -6,6 +6,12 @@ test('equal', function (t) {
     { a: [2, 3], b: [4] },
     { a: [2, 3], b: [4] }
   ));
+
+  t.ok(equal(
+    new Map([['a', 1], ['b', 2]]),
+    new Map([['b', 2], ['a', 1]])
+  ));
+
   t.end();
 });
 
@@ -14,6 +20,16 @@ test('not equal', function (t) {
     { x: 5, y: [6] },
     { x: 5, y: 6 }
   ));
+
+  t.notOk(equal(
+    new Map([['a', [1, 2]]]),
+    new Map([['a', [2, 1]]])
+  ));
+  t.notOk(equal(
+    new Map([['a', 1]]),
+    new Map([['b', 1]])
+  ));
+
   t.end();
 });