Fix 'required' implementation

Now it doesn't rely on undeclared variables anymore.

Fixes: #179

Author: ChALkeR

index.js

@@ -243,19 +243,20 @@ var compile = function(schema, cache, root, reporter, opts) {
     }
 
     if (Array.isArray(node.required)) {
+      var n = gensym('missing')
+      validate('var %s = 0', n)
       var checkRequired = function (req) {
         var prop = genobj(name, req);
         validate('if (%s === undefined) {', prop)
         error('is required', prop)
-        validate('missing++')
+        validate('%s++', n)
         validate('}')
       }
       validate('if ((%s)) {', type !== 'object' ? types.object(name) : 'true')
-      validate('var missing = 0')
       node.required.map(checkRequired)
       validate('}');
       if (!greedy) {
-        validate('if (missing === 0) {')
+        validate('if (%s === 0) {', n)
         indent++
       }
     }

test/required-unique-noconflict.js

@@ -0,0 +1,19 @@
+const tape = require('tape')
+const validator = require('..')
+
+tape('required + uniqueItems', (t) => {
+  const validate = validator({ required: ['a'], uniqueItems: true })
+  t.notOk(validate([1, 1]), 'required + uniqueItems')
+  t.end()
+})
+
+tape('required + uniqueItems inside allOf', (t) => {
+  const validate = validator({
+    required: ['a'],
+    allOf: [
+      { required: ['b'], uniqueItems: true }
+    ]
+  })
+  t.notOk(validate([1, 1]), 'required + uniqueItems in allOf')
+  t.end()
+})