[falahat]

Description

Stacked on #11282. App Hosting and Cloud Run each had their own copy of the local build steps: copy the project to a scratch folder, build it with Universal Maker, tar the output, and delete the folder. A fix like #11396 had to be made in both copies.

Both now call buildLocally() in apphosting/localBuild.ts. Each product keeps only its own build env, Node.js version check, and rollout.

Behavior changes:

• App Hosting tars right after building, in prepare. Its deploy step only uploads.
• The scratch folder is deleted right after the build, even if the build fails. App Hosting used to leave it behind on failure.

Tip: hide whitespace when reviewing apphosting/deploy.ts; most of its diff is re-indentation.

Scenarios Tested

• Unit tests: a new localBuild.spec.ts runs the shared copy → build → tar → cleanup on a real temp project, with only Universal Maker faked. It covers cleanup after a failed build, and a failed cleanup not hiding the build error.
• Local Builds on Cloud Run and App Hosting still deploy for a Turborepo, an Nx repo, and an app at the project root (Turborepo and Nx checked with Run Local Builds from the folder App Hosting's preparer picks #11396 on top, which doesn't change their build folder). A self-contained app in a subfolder still fails the same way, which Run Local Builds from the folder App Hosting's preparer picks #11396 fixes. No scratch folders are left behind, including after failed builds.

Sample Commands

# With "localBuild": true on the service or backend in firebase.json:
firebase deploy --only run:web
firebase deploy --only apphosting:web

[gemini-code-assist]

Code Review

This pull request refactors the local build process for App Hosting and Cloud Run by introducing a unified buildLocally function in a new localBuild.ts module. This consolidates the steps of preparing a scratch directory, running the build, and packaging the output into a tarball, simplifying the LocalBuild interface to use a single archive path. The feedback recommends refactoring the buildLocally function signature to accept a single options object instead of five positional arguments, in accordance with the repository's style guide, and provides corresponding updates for its callers and tests.

[gemini-code-assist]

According to the repository style guide (GEMINI.md, line 55), functions accepting more than three arguments should accept a single options object instead of individual positional arguments. This improves maintainability and makes future signature changes easier.

export interface BuildLocallyOptions {
  projectId: string;
  projectDir: string;
  config: AppHostingSingle;
  env: EnvMap;
  scratchDir: string;
  nonInteractive?: boolean;
  allowLocalBuildSecrets?: boolean;
}

export async function buildLocally(options: BuildLocallyOptions): Promise<PackagedLocalBuild> {
  const {
    projectId,
    projectDir,
    config,
    env,
    scratchDir,
    nonInteractive,
    allowLocalBuildSecrets,
  } = options;

References

1. Functions accepting more than three arguments should accept a single options object ({ project, force }). ^(link)

[gemini-code-assist]

Update the call to buildLocally to pass a single options object, matching the refactored signature.

      const { archive, buildConfig } = await buildLocally({
        projectId,
        projectDir: rootDir,
        config: cfg,
        env: buildEnv[cfg.backendId] || {},
        scratchDir: localBuildScratchDir,
        nonInteractive: options.nonInteractive,
        allowLocalBuildSecrets: !!options.allowLocalBuildSecrets,
      });

[gemini-code-assist]

Update the call to buildLocally to pass a single options object, matching the refactored signature.

  const { archive, buildConfig } = await buildLocally({
    projectId: context.projectId,
    projectDir: options.config.projectDir,
    config: cfg,
    env: toLocalBuildEnv(svc.buildEnv || {}),
    scratchDir: fs.mkdtempSync(path.join(os.tmpdir(), `run-local-build-${serviceId}-`)),
    allowLocalBuildSecrets: true,
  });

[gemini-code-assist]

Update the test helper to call buildLocally with a single options object.

    return buildLocally({
      projectId: "my-project",
      projectDir,
      config,
      env,
      scratchDir,
      allowLocalBuildSecrets: true,
    });

[gemini-code-assist]

Update the assertion to match the single options object signature of buildLocally.

Suggested change

	expect(buildLocallyStub).to.have.been.calledWithMatch(
	"my-project",
	scratchDir,
	"/project",
	{ backendId: "web", rootDir: "apps/web", localBuild: true },
	{},
	{ rootDir: "apps/web" },
	{ scratchDir },
	);
	expect(buildLocallyStub).to.have.been.calledWithMatch({
	projectId: "my-project",
	projectDir: "/project",
	config: { backendId: "web", rootDir: "apps/web", localBuild: true },
	env: {},
	scratchDir,
	});