fix: concat with lazy

jquense · Feb 6, 2019 · e250193 · e250193
1 parent 2e87196
commit e250193
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Showing 3 changed files with 14 additions and 1 deletion.
diff --git a/src/mixed.js b/src/mixed.js
@@ -103,7 +103,7 @@ const proto = (SchemaType.prototype = {
   },
 
   concat(schema) {
-    if (!schema) return this;
+    if (!schema || schema === this) return this;
 
     if (schema._type !== this._type && this._type !== 'mixed')
       throw new TypeError(

diff --git a/src/util/merge.js b/src/util/merge.js
@@ -11,6 +11,8 @@ export default function merge(target, source) {
 
       if (sourceVal === undefined) {
         source[key] = targetVal;
+      } else if (sourceVal === targetVal) {
+        continue;
       } else if (isSchema(sourceVal)) {
         if (isSchema(targetVal)) source[key] = targetVal.concat(sourceVal);
       } else if (isObject(sourceVal)) {

diff --git a/test/yup.js b/test/yup.js
@@ -54,6 +54,17 @@ describe('Yup', function() {
     });
   });
 
+  it('should not merge needlesly', function() {
+    var schema = string();
+    var spy = sinon.spy(schema, 'concat');
+    var a = { schema };
+    var b = { schema };
+    var c = merge(a, b);
+
+    c.schema.should.equal(schema);
+    spy.should.not.have.been.called();
+  });
+
   it('should getIn correctly', async () => {
     var num = number(),
       inst = object().shape({