Add support for internal testing-only commands. (#5289)

* Add support for internal testing-only commands.

* Word smith-ing.

Author: taeold

src/commands/index.ts

@@ -143,6 +143,9 @@ export function load(client: any): any {
   client.hosting.sites.get = loadCommand("hosting-sites-get");
   client.hosting.sites.list = loadCommand("hosting-sites-list");
   client.init = loadCommand("init");
+  if (experiments.isEnabled("internaltesting")) {
+    client.internaltesting = {};
+  }
   client.login = loadCommand("login");
   client.login.add = loadCommand("login-add");
   client.login.ci = loadCommand("login-ci");

src/experiments.ts

@@ -97,11 +97,17 @@ export const ALL_EXPERIMENTS = experiments({
       "if any service exceeds 500 tags, but it is theoretically possible that a project " +
       "exceeds the region-wide limit of tags and an old site version fails",
   },
-
   // Access experiments
   crossservicerules: {
     shortDescription: "Allow Firebase Rules to reference resources in other services",
   },
+  internaltesting: {
+    shortDescription: "Exposes Firebase CLI commands intended for internal testing purposes.",
+    fullDescription:
+      "Exposes Firebase CLI commands intended for internal testing purposes. " +
+      "These commands are not meant for public consumption and may break or disappear " +
+      "without a notice.",
+  },
 });
 
 export type ExperimentName = keyof typeof ALL_EXPERIMENTS;