Resolves insertion order mismatch in array-union examples (#503)

README.md

@@ -1507,7 +1507,7 @@ Returns the union of two arrays
 ```js
 import union from 'just-union';
 
-union([1, 2, 5, 6], [2, 3, 4, 6]); // [1, 2, 3, 4, 5, 6]
+union([1, 2, 5, 6], [2, 3, 4, 6]); // [1, 2, 5, 6, 3, 4]
 ```
 
 ### [just-zip-it](https://www.npmjs.com/package/just-zip-it)

md-variables.json

@@ -387,7 +387,7 @@
     "examples": [
       "import union from 'just-union';",
       "",
-      "union([1, 2, 5, 6], [2, 3, 4, 6]); // [1, 2, 3, 4, 5, 6]"
+      "union([1, 2, 5, 6], [2, 3, 4, 6]); // [1, 2, 5, 6, 3, 4]"
     ]
   },
   "just-unique": {

packages/array-union/README.md

@@ -20,5 +20,5 @@ Returns the union of two arrays
 ```js
 import union from 'just-union';
 
-union([1, 2, 5, 6], [2, 3, 4, 6]); // [1, 2, 3, 4, 5, 6]
+union([1, 2, 5, 6], [2, 3, 4, 6]); // [1, 2, 5, 6, 3, 4]
 ```

packages/array-union/index.js

@@ -1,7 +1,7 @@
 module.exports = union;
 
 /*
-  union([1, 2, 5, 6], [2, 3, 4, 6]); // [1, 2, 3, 4, 5, 6]
+  union([1, 2, 5, 6], [2, 3, 4, 6]); // [1, 2, 5, 6, 3, 4]
 */
 
 function union(arr1, arr2) {

packages/array-union/index.mjs

@@ -1,7 +1,7 @@
 var arrayUnion = union;
 
 /*
-  union([1, 2, 5, 6], [2, 3, 4, 6]); // [1, 2, 3, 4, 5, 6]
+  union([1, 2, 5, 6], [2, 3, 4, 6]); // [1, 2, 5, 6, 3, 4]
 */
 
 function union(arr1, arr2) {

test/array-union/index.js

@@ -25,6 +25,14 @@ test('does not mutate', function(t) {
   t.end();
 });
 
+test('respects insertion order', function(t) {
+  t.plan(1);
+  var arr1 = [1, 2, 5, 6];
+  var arr2 = [2, 3, 4, 6];
+  t.deepEqual(union(arr1, arr2), [1, 2, 5, 6, 3, 4]);
+  t.end();
+});
+
 test("throws if first two arguments aren't arrays", function(t) {
   t.plan(8);
   var arr1 = [1, 2, 3, 4, 5];