Install preloaded plugins

Change-Id: Ib5695451a77cd047ee05b85da71d2ea895fb59d7

polygerrit-ui/app/elements/plugins/gr-plugin-host/gr-plugin-host.js

@@ -37,9 +37,10 @@
       const jsPlugins =
           this._handleMigrations(plugins.js_resource_paths || [], htmlPlugins);
       const defaultTheme = config.default_theme;
-      const pluginsPending =
-          [].concat(jsPlugins, htmlPlugins, defaultTheme || []).map(
-              p => this._urlFor(p));
+      const pluginsPending = []
+          .concat(jsPlugins, htmlPlugins, defaultTheme || [])
+          .filter(p => !Gerrit._isPluginPreloaded(p))
+          .map(p => this._urlFor(p));
       Gerrit._setPluginsPending(pluginsPending);
       if (defaultTheme) {
         // Make theme first to be first to load.

polygerrit-ui/app/elements/plugins/gr-plugin-host/gr-plugin-host_test.html

@@ -187,5 +187,21 @@ limitations under the License.
       element.importHref.secondCall.args[2]();
       assert.equal(Gerrit._pluginInstallError.callCount, 2);
     });
+
+    test('skips preloaded plugins', () => {
+      sandbox.stub(Gerrit, '_isPluginPreloaded')
+          .withArgs('plugins/foo/bar').returns(true)
+          .withArgs('plugins/42').returns(true);
+      sandbox.stub(Gerrit, '_setPluginsCount');
+      sandbox.stub(Gerrit, '_setPluginsPending');
+      element.config = {
+        plugin: {
+          html_resource_paths: ['plugins/foo/bar', 'plugins/baz'],
+          js_resource_paths: ['plugins/42'],
+        },
+      };
+      assert.isTrue(
+          Gerrit._setPluginsPending.calledWith([url + '/plugins/baz']));
+    });
   });
 </script>

polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-js-api-interface_test.html

@@ -412,6 +412,15 @@ limitations under the License.
           element.EventType.ADMIN_MENU_LINKS);
     });
 
+    test('preloaded plugins are installed', () => {
+      const installStub = sandbox.stub();
+      Gerrit._preloadedPlugins = {foo: installStub};
+      Gerrit._installPreloadedPlugins();
+      assert.isTrue(installStub.called);
+      const pluginApi = installStub.lastCall.args[0];
+      assert.strictEqual(pluginApi.getPluginName(), 'foo');
+    });
+
     suite('test plugin with base url', () => {
       setup(() => {
         sandbox.stub(Gerrit.BaseUrlBehavior, 'getBaseUrl').returns('/r');

polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-public-js-api.js

@@ -31,6 +31,8 @@
 
   let _pluginsPendingCount = -1;
 
+  const PRELOADED_PROTOCOL = 'preloaded:';
+
   const UNKNOWN_PLUGIN = 'unknown';
 
   const PANEL_ENDPOINTS_MAPPING = {
@@ -101,6 +103,15 @@
   // http://www.gwtproject.org/doc/latest/DevGuideCodingBasicsJSNI.html
   window.$wnd = window;
 
+  function installPreloadedPlugins() {
+    if (!Gerrit._preloadedPlugins) { return; }
+    for (const name in Gerrit._preloadedPlugins) {
+      if (!Gerrit._preloadedPlugins.hasOwnProperty(name)) { continue; }
+      const callback = Gerrit._preloadedPlugins[name];
+      Gerrit.install(callback, API_VERSION, PRELOADED_PROTOCOL + name);
+    }
+  }
+
   function getPluginNameFromUrl(url) {
     if (!(url instanceof URL)) {
       try {
@@ -110,6 +121,9 @@
         return null;
       }
     }
+    if (url.protocol === PRELOADED_PROTOCOL) {
+      return url.pathname;
+    }
     const base = Gerrit.BaseUrlBehavior.getBaseUrl();
     const pathname = url.pathname.replace(base, '');
     // Site theme is server from predefined path.
@@ -432,6 +446,7 @@
   const app = document.querySelector('#app');
   if (!app) {
     // No gr-app found (running tests)
+    Gerrit._installPreloadedPlugins = installPreloadedPlugins;
     Gerrit._resetPlugins = () => {
       _allPluginsPromise = null;
       _pluginsInstalled = [];
@@ -622,5 +637,18 @@
     return `${pluginName}-screen-${screenName}`;
   };
 
+  Gerrit._isPluginPreloaded = function(url) {
+    const name = getPluginNameFromUrl(url);
+    if (name && Gerrit._preloadedPlugins) {
+      return name in Gerrit._preloadedPlugins;
+    } else {
+      return false;
+    }
+  };
+
   window.Gerrit = Gerrit;
+
+  // Preloaded plugins should be installed after Gerrit.install() is set,
+  // since plugin preloader substitutes Gerrit.install() temporarily.
+  installPreloadedPlugins();
 })(window);