Use correct property when determining display URL

Closes #5574

ghost/admin/app/components/gh-navitem-url-input.js

@@ -19,7 +19,7 @@ export default Ember.TextField.extend({
 
         // if we have a relative url, create the absolute url to be displayed in the input
         // if (this.get('isRelative')) {
-        if (!validator.isURL(url) && this.get('value').indexOf('mailto:') !== 0) {
+        if (!validator.isURL(url) && url.indexOf('mailto:') !== 0) {
             url = joinUrlParts(baseUrl, url);
         }
 

ghost/admin/tests/unit/components/gh-navitem-url-input-test.js

@@ -0,0 +1,103 @@
+/* jshint expr:true */
+import Ember from 'ember';
+import {expect} from 'chai';
+import {
+    describeComponent,
+    it
+} from 'ember-mocha';
+
+describeComponent(
+    'gh-navitem-url-input',
+    'GhNavitemUrlInputComponent',
+    {},
+    function () {
+        it('renders', function () {
+            var component = this.subject();
+
+            expect(component._state).to.equal('preRender');
+
+            this.render();
+
+            expect(component._state).to.equal('inDOM');
+        });
+
+        it('renders correctly with a URL that matches the base URL', function () {
+            var component = this.subject({
+                baseUrl: 'http://example.com/'
+            });
+
+            Ember.run(function () {
+                component.set('value', 'http://example.com/');
+            });
+
+            this.render();
+
+            expect(this.$().val()).to.equal('http://example.com/');
+        });
+
+        it('renders correctly with a relative URL', function () {
+            var component = this.subject({
+                baseUrl: 'http://example.com/'
+            });
+
+            Ember.run(function () {
+                component.set('value', '/go/docs');
+            });
+
+            this.render();
+
+            expect(this.$().val()).to.equal('/go/docs');
+        });
+
+        it('renders correctly with a mailto URL', function () {
+            var component = this.subject({
+                baseUrl: 'http://example.com/'
+            });
+
+            Ember.run(function () {
+                component.set('value', 'mailto:someone@example.com');
+            });
+
+            this.render();
+
+            expect(this.$().val()).to.equal('mailto:someone@example.com');
+        });
+
+        it('identifies a URL as relative', function () {
+            var component = this.subject({
+                baseUrl: 'http://example.com/',
+                url: '/go/docs'
+            });
+
+            this.render();
+
+            expect(component.get('isRelative')).to.be.ok;
+
+            Ember.run(function () {
+                component.set('value', 'http://example.com/go/docs');
+            });
+
+            expect(component.get('isRelative')).to.not.be.ok;
+        });
+
+        it('identifies a URL as the base URL', function () {
+            var component = this.subject({
+                baseUrl: 'http://example.com/'
+            });
+
+            this.render();
+
+            Ember.run(function () {
+                component.set('value', 'http://example.com/');
+            });
+
+            expect(component.get('isBaseUrl')).to.be.ok;
+
+            Ember.run(function () {
+                component.set('value', 'http://example.com/go/');
+            });
+
+            expect(component.get('isBaseUrl')).to.not.be.ok;
+        });
+    }
+);