fix(server): t3 service uninstall leaves another T3 home's service alone

apps/server/src/cli/service.test.ts

@@ -32,6 +32,7 @@ function makeTestService(
 ) {
   const installOptions: Array<Parameters<BootService.BootService["Service"]["install"]>[0]> = [];
   const restarts: Array<true> = [];
+  const uninstalls: Array<true> = [];
   const service = BootService.BootService.of({
     status: Effect.succeed(serviceStatus),
     withStopped: (operation) => operation,
@@ -49,9 +50,12 @@ function makeTestService(
           logPath: serviceStatus.logPath,
         };
       }),
-    uninstall: Effect.succeed(false),
+    uninstall: Effect.sync(() => {
+      uninstalls.push(true);
+      return serviceStatus.installed;
+    }),
   });
-  return { service, installOptions, restarts };
+  return { service, installOptions, restarts, uninstalls };
 }
 
 it.layer(Layer.mergeAll(NodeServices.layer, NetService.layer))("service commands", (it) => {
@@ -194,4 +198,48 @@ it.layer(Layer.mergeAll(NodeServices.layer, NetService.layer))("service commands
         expect(installOptions).toEqual([]);
       }),
   );
+
+  it.effect.each([
+    { label: "this home's service", otherHome: false, unreadable: false, removed: [true] },
+    { label: "another home's service", otherHome: true, unreadable: false, removed: [] },
+    { label: "an unreadable service", otherHome: false, unreadable: true, removed: [true] },
+  ])("uninstall removes only $label", (input) =>
+    Effect.gen(function* () {
+      const fs = yield* FileSystem.FileSystem;
+      const baseDir = yield* fs.makeTempDirectoryScoped({ prefix: "t3-service-cli-test-" });
+      const { service, uninstalls } = makeTestService({
+        ...status,
+        installedBaseDir: input.otherHome ? "/home/me/.t3" : baseDir,
+      });
+      vi.spyOn(BootService, "layer").mockReturnValue(
+        Layer.succeed(
+          BootService.BootService,
+          input.unreadable
+            ? {
+                ...service,
+                status: Effect.fail(new BootService.BootServiceInstallError({ cause: "EACCES" })),
+              }
+            : service,
+        ),
+      );
+
+      const output = yield* Command.runWith(serviceCommand, { version: packageJson.version })([
+        "uninstall",
+        "--base-dir",
+        baseDir,
+      ]).pipe(
+        Effect.andThen(TestConsole.logLines),
+        Effect.map((lines) => lines.join("\n")),
+        Effect.provideService(HostProcess.Environment, {}),
+        Effect.provide(
+          Layer.mergeAll(
+            ConfigProvider.layer(ConfigProvider.fromEnv({ env: {} })),
+            Layer.fresh(TestConsole.layer),
+          ),
+        ),
+      );
+      expect(uninstalls).toEqual(input.removed);
+      expect(output).toContain(input.otherHome ? "another T3 home" : "Removed");
+    }),
+  );
 });

apps/server/src/cli/service.ts

@@ -278,6 +278,22 @@ const serviceUninstallCommand = Command.make("uninstall", projectLocationFlags).
       flags,
       Effect.gen(function* () {
         const service = yield* BootService.BootService;
+        const path = yield* Path.Path;
+        const { baseDir } = yield* ServerConfig.ServerConfig;
+        // An unreadable unit stays removable; only a unit known to serve another home is kept.
+        const installedBaseDir = yield* service.status.pipe(
+          Effect.map((status) => status.installedBaseDir),
+          Effect.orElseSucceed(() => undefined),
+        );
+        if (
+          installedBaseDir !== undefined &&
+          path.resolve(installedBaseDir) !== path.resolve(baseDir)
+        ) {
+          yield* Console.log(
+            "The installed service runs another T3 home, so it was not removed. Pass its --base-dir.",
+          );
+          return;
+        }
         const removed = yield* service.uninstall;
         yield* Console.log(
           removed ? "Removed the T3 Code service." : "T3 Code service is not installed.",