Add basic "crate navigation tabs" test

Author: Turbo87

app/components/nav-tabs/tab.hbs

@@ -2,6 +2,7 @@
   <a
     href={{@link.url}}
     local-class="link {{if @link.isActive "active"}}"
+    data-test-active={{@link.isActive}}
     {{on "click" @link.transitionTo}}
   >
     {{yield}}

tests/acceptance/crate-navtabs-test.js

@@ -0,0 +1,51 @@
+import { click, currentURL, visit } from '@ember/test-helpers';
+import { module, test } from 'qunit';
+
+import { setupApplicationTest } from 'cargo/tests/helpers';
+
+const TAB_README = '[data-test-readme-tab] a';
+const TAB_VERSIONS = '[data-test-versions-tab] a';
+const TAB_REV_DEPS = '[data-test-rev-deps-tab] a';
+const TAB_SETTINGS = '[data-test-settings-tab] a';
+
+module('Acceptance | crate navigation tabs', function (hooks) {
+  setupApplicationTest(hooks);
+
+  test('basic navigation between tabs works as expected', async function (assert) {
+    this.server.create('crate', { name: 'nanomsg' });
+    this.server.create('version', { crateId: 'nanomsg', num: '0.6.1' });
+
+    await visit('/crates/nanomsg');
+    assert.equal(currentURL(), '/crates/nanomsg');
+
+    assert.dom(TAB_README).hasAttribute('href', '/crates/nanomsg').hasAttribute('data-test-active');
+    assert.dom(TAB_VERSIONS).hasAttribute('href', '/crates/nanomsg/versions').hasNoAttribute('data-test-active');
+    assert
+      .dom(TAB_REV_DEPS)
+      .hasAttribute('href', '/crates/nanomsg/reverse_dependencies')
+      .hasNoAttribute('data-test-active');
+    assert.dom(TAB_SETTINGS).doesNotExist();
+
+    await click(TAB_VERSIONS);
+    assert.equal(currentURL(), '/crates/nanomsg/versions');
+
+    assert.dom(TAB_README).hasAttribute('href', '/crates/nanomsg').hasNoAttribute('data-test-active');
+    assert.dom(TAB_VERSIONS).hasAttribute('href', '/crates/nanomsg/versions').hasAttribute('data-test-active');
+    assert
+      .dom(TAB_REV_DEPS)
+      .hasAttribute('href', '/crates/nanomsg/reverse_dependencies')
+      .hasNoAttribute('data-test-active');
+    assert.dom(TAB_SETTINGS).doesNotExist();
+
+    await click(TAB_REV_DEPS);
+    assert.equal(currentURL(), '/crates/nanomsg/reverse_dependencies');
+
+    assert.dom(TAB_README).hasAttribute('href', '/crates/nanomsg').hasNoAttribute('data-test-active');
+    assert.dom(TAB_VERSIONS).hasAttribute('href', '/crates/nanomsg/versions').hasNoAttribute('data-test-active');
+    assert
+      .dom(TAB_REV_DEPS)
+      .hasAttribute('href', '/crates/nanomsg/reverse_dependencies')
+      .hasAttribute('data-test-active');
+    assert.dom(TAB_SETTINGS).doesNotExist();
+  });
+});