[Breaking] comparing arrays and objects should always fail, per node‘…

…s assert.deepEqual

Fixes #12.

Relates to tape-testing/tape#186

index.js

@@ -3,6 +3,7 @@ var isArguments = require('is-arguments');
 var is = require('object-is');
 var isRegex = require('is-regex');
 var flags = require('regexp.prototype.flags');
+var isArray = require('isarray');
 
 function deepEqual(actual, expected, options) {
   var opts = options || {};
@@ -12,6 +13,12 @@ function deepEqual(actual, expected, options) {
     return true;
   }
 
+  var actualIsArray = isArray(actual);
+  var expectedIsArray = isArray(expected);
+  if (actualIsArray !== expectedIsArray) {
+    return false;
+  }
+
   var actualIsRegex = isRegex(actual);
   var expectedIsRegex = isRegex(expected);
   if (actualIsRegex || expectedIsRegex) {

package.json

@@ -17,6 +17,7 @@
   "dependencies": {
     "is-arguments": "^1.0.4",
     "is-regex": "^1.0.4",
+    "isarray": "^2.0.5",
     "object-is": "^1.0.1",
     "object-keys": "^1.1.1",
     "regexp.prototype.flags": "^1.2.0"

test/cmp.js

@@ -284,23 +284,23 @@ test('regexen', function (t) {
 });
 
 test('arrays and objects', function (t) {
-  t.ok(equal([], {}), 'empty array and empty object are equal');
-  t.ok(equal({}, []), 'empty object and empty array are equal');
+  t.notOk(equal([], {}), 'empty array and empty object are not equal');
+  t.notOk(equal({}, []), 'empty object and empty array are not equal');
 
-  t.ok(equal([], {}, { strict: true }), 'strict: empty array and empty object are equal');
-  t.ok(equal({}, [], { strict: true }), 'strict: empty object and empty array are equal');
+  t.notOk(equal([], {}, { strict: true }), 'strict: empty array and empty object are not equal');
+  t.notOk(equal({}, [], { strict: true }), 'strict: empty object and empty array are not equal');
 
   t.notOk(equal([], { length: 0 }), 'empty array and empty arraylike object are not equal');
   t.notOk(equal({ length: 0 }, []), 'empty arraylike object and empty array are not equal');
 
   t.notOk(equal([], { length: 0 }, { strict: true }), 'strict: empty array and empty arraylike object are not equal');
   t.notOk(equal({ length: 0 }, [], { strict: true }), 'strict: empty arraylike object and empty array are not equal');
 
-  t.ok(equal([1], { 0: 1 }), 'array and object are equal');
-  t.ok(equal({ 0: 1 }, [1]), 'object and array are equal');
+  t.notOk(equal([1], { 0: 1 }), 'array and object are not equal');
+  t.notOk(equal({ 0: 1 }, [1]), 'object and array are not equal');
 
-  t.ok(equal([1], { 0: 1 }, { strict: true }), 'strict: array and object are equal');
-  t.ok(equal({ 0: 1 }, [1], { strict: true }), 'strict: object and array are equal');
+  t.notOk(equal([1], { 0: 1 }, { strict: true }), 'strict: array and object are not equal');
+  t.notOk(equal({ 0: 1 }, [1], { strict: true }), 'strict: object and array are not equal');
 
   t.end();
 });