fix #2255, avoid adding overrides upon import when a component overri…

…des has not changed (#2257)

CHANGELOG.md

@@ -7,6 +7,7 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 
 ## [unreleased]
 
+- [#2255](https://github.com/teambit/bit/issues/2255) avoid adding unneeded overrides upon import
 - [#2247](https://github.com/teambit/bit/issues/2247) improve auto-tag output
 
 ## [[14.7.2] - 2020-01-12](https://github.com/teambit/bit/releases/tag/v14.7.2)

e2e/functionalities/workspace-config.e2e.3.ts

@@ -1717,4 +1717,19 @@ describe('workspace config', function() {
       });
     });
   });
+  describe('export a component with compiler then import', () => {
+    before(() => {
+      helper.scopeHelper.setNewLocalAndRemoteScopes();
+      helper.fixtures.createComponentBarFoo();
+      helper.fixtures.addComponentBarFoo();
+      helper.env.importDummyCompiler();
+      helper.command.tagAllComponents();
+      helper.command.exportAllComponents();
+      helper.command.importComponent('bar/foo');
+    });
+    it('should not add the component into the overrides of the workspace because nothing has changed', () => {
+      const bitJson = helper.bitJson.read();
+      expect(bitJson).to.not.have.property('overrides');
+    });
+  });
 });

src/consumer/config/consumer-overrides.ts

@@ -168,7 +168,7 @@ export default class ConsumerOverrides {
   ): boolean {
     // seems like R.equals does a great job here. it compares objects by values (not by reference).
     // also it disregards the keys order.
-    return R.equals(overridesA, overridesB);
+    return R.equals(overridesA || {}, overridesB || {});
   }
 
   findExactMatch(bitId: BitId): string | null | undefined {