feat: expose oneOf and notOneOf values on description (#885)

* [tests] Add test

* Expose blacklist and whitelist values

* Add tests

* whitelist -> oneOf, blacklist -> notOneOf

src/mixed.js

@@ -17,6 +17,17 @@ class RefSet {
     this.list = new Set();
     this.refs = new Map();
   }
+  get size() {
+    return this.list.size + this.refs.size;
+  }
+  describe() {
+    const description = [];
+
+    for (const item of this.list) description.push(item);
+    for (const [, ref] of this.refs) description.push(ref.describe());
+
+    return description;
+  }
   toArray() {
     return toArray(this.list).concat(toArray(this.refs.values()));
   }
@@ -528,8 +539,7 @@ const proto = (SchemaType.prototype = {
 
   describe() {
     const next = this.clone();
-
-    return {
+    const description = {
       type: next._type,
       meta: next._meta,
       label: next._label,
@@ -538,7 +548,12 @@ const proto = (SchemaType.prototype = {
         .filter(
           (n, idx, list) => list.findIndex(c => c.name === n.name) === idx,
         ),
-    };
+    }
+
+    if (next._whitelist.size) description.oneOf = next._whitelist.describe();
+    if (next._blacklist.size) description.notOneOf = next._blacklist.describe();
+
+    return description;
   },
 
   defined(message = locale.defined) {

test/mixed.js

@@ -888,7 +888,9 @@ describe('Mixed Types ', () => {
       bar: string()
         .max(2)
         .meta({ input: 'foo' })
-        .label('str!'),
+        .label('str!')
+        .oneOf(['a', 'b'])
+        .notOneOf([ref('foo')]),
     }).describe();
 
     desc.should.eql({
@@ -926,6 +928,11 @@ describe('Mixed Types ', () => {
           meta: {
             input: 'foo',
           },
+          oneOf: ['a', 'b'],
+          notOneOf: [{
+            type: 'ref',
+            key: 'foo'
+          }]
         },
       },
     });