Fix for bug with toggling opensInNewWindow state (#17794)

* Update getDerivedStateFromProps to pass back all state property changes

* Add test to check that state.opensInNewWindow is set correctly on prop change

* Rename test file

packages/format-library/src/link/inline.js

@@ -89,13 +89,15 @@ class InlineLinkUI extends Component {
 		const opensInNewWindow = target === '_blank';
 
 		if ( ! isShowingInput( props, state ) ) {
+			const update = {};
 			if ( url !== state.inputValue ) {
-				return { inputValue: url };
+				update.inputValue = url;
 			}
 
 			if ( opensInNewWindow !== state.opensInNewWindow ) {
-				return { opensInNewWindow };
+				update.opensInNewWindow = opensInNewWindow;
 			}
+			return Object.keys( update ).length ? update : null;
 		}
 
 		return null;

packages/format-library/src/link/test/inline.js

@@ -0,0 +1,38 @@
+/**
+ * Internal dependencies
+ */
+import InlineLinkUI from '../inline';
+/**
+ * External dependencies
+ */
+import { shallow } from 'enzyme';
+
+describe( 'InlineLinkUI', () => {
+	it( 'InlineLinkUI renders', () => {
+		const wrapper = shallow(
+			<InlineLinkUI />
+		);
+		expect( wrapper ).toBeTruthy();
+	} );
+
+	it( 'should set state.opensInNewWindow to false by default', () => {
+		const wrapper = shallow(
+			<InlineLinkUI activeAttributes={ {} } />
+		).dive();
+
+		expect( wrapper.state( 'opensInNewWindow' ) ).toEqual( false );
+	} );
+
+	it( 'should set state.opensInNewWindow to true if props.activeAttributes.target is _blank', () => {
+		const givenProps = {
+			addingLink: false,
+			activeAttributes: { url: 'http://www.google.com', target: '_blank' },
+		};
+
+		const wrapper = shallow(
+			<InlineLinkUI activeAttributes={ {} } />
+		).dive();
+		wrapper.setProps( givenProps );
+		expect( wrapper.state( 'opensInNewWindow' ) ).toEqual( true );
+	} );
+} );