[Fix] ensure Buffer + non-Buffer comparison order does not matter

Author: ljharb

index.js

@@ -67,10 +67,10 @@ function objEquiv(a, b, opts) {
     return a.getTime() === b.getTime();
   }
 
-  if (isBuffer(a)) {
-    if (!isBuffer(b)) {
-      return false;
-    }
+  var aIsBuffer = isBuffer(a);
+  var bIsBuffer = isBuffer(b);
+  if (aIsBuffer !== bIsBuffer) { return false; }
+  if (aIsBuffer || bIsBuffer) { // && would work too, because both are true or both false here
     if (a.length !== b.length) { return false; }
     for (i = 0; i < a.length; i++) {
       if (a[i] !== b[i]) { return false; }

test/cmp.js

@@ -72,7 +72,19 @@ test('dates', function (t) {
 
 test('buffers', function (t) {
   /* eslint no-buffer-constructor: 1, new-cap: 1 */
-  t.ok(equal(Buffer('xyz'), Buffer('xyz')));
+  t.ok(equal(Buffer('xyz'), Buffer('xyz')), 'buffers with same contents are equal');
+  t.ok(equal(Buffer('xyz'), Buffer('xyz'), { strict: true }), 'strict: buffers with same contents are equal');
+
+  t.notOk(equal(Buffer('abc'), Buffer('xyz')), 'buffers with different contents are not equal');
+  t.notOk(equal(Buffer('xyz'), Buffer('abc')), 'buffers with different contents are not equal');
+  t.notOk(equal(Buffer('abc'), Buffer('xyz'), { strict: true }), 'strict: buffers with different contents are not equal');
+  t.notOk(equal(Buffer('xyz'), Buffer('abc'), { strict: true }), 'strict: buffers with different contents are not equal');
+
+  t.notOk(equal(Buffer(''), []), 'empty buffer and empty array are not equal');
+  t.notOk(equal([], Buffer('')), 'empty array and empty buffer are not equal');
+  t.notOk(equal(Buffer(''), [], { strict: true }), 'strict: empty buffer and empty array are not equal');
+  t.notOk(equal([], Buffer(''), { strict: true }), 'strict: empty array and empty buffer are not equal');
+
   t.end();
 });