ui: 1.15.x back to hcp link conditions (#19444)

Only show back to hcp link if CONSUL_HCP_URL is present

.changelog/19444.txt

@@ -0,0 +1,3 @@
+```release-note:bug
+ui: only show back-to-hcp link when url is present
+```

ui/packages/consul-hcp/app/components/consul/hcp/home/index.hbs

@@ -1,8 +1,10 @@
-<div
-  class="consul-hcp-home"
-  ...attributes
->
-  <a href={{env 'CONSUL_HCP_URL'}} data-native-href="true">
-    Back to HCP
-  </a>
-</div>
+{{#if (env 'CONSUL_HCP_URL')}}
+  <div
+    class="consul-hcp-home"
+    ...attributes
+  >
+    <a href={{env 'CONSUL_HCP_URL'}} data-native-href="true">
+      Back to HCP
+    </a>
+  </div>
+{{/if}}

ui/packages/consul-hcp/app/components/consul/hcp/home/index.test.js

@@ -35,4 +35,34 @@ module('Integration | Component | consul hcp home', function(hooks) {
     assert.dom('a').hasAttribute('href', 'http://hcp');
 
   });
+
+  test('it does not output the Back to HCP link if CONSUL_HCP_URL is not present', async function(assert) {
+    // temporary registration until we are running as separate applications
+    this.owner.register(
+      'component:consul/hcp/home',
+      ConsulHcpHome
+    );
+    //
+
+    const Helper = this.owner.resolveRegistration('helper:env');
+    this.owner.register(
+      'helper:env',
+      class extends Helper {
+        compute([name, def]) {
+          switch(name) {
+            case 'CONSUL_HCP_URL':
+              return undefined;
+          }
+          return super.compute(...arguments);
+        }
+      }
+    );
+
+    await render(hbs`
+      <Consul::Hcp::Home />
+    `);
+
+    assert.dom('[data-test-back-to-hcp]').doesNotExist();
+    assert.dom('a').doesNotExist();
+  });
 });