E2E Container Testing

Test the installer binary inside Docker containers running the supported Linux distributions.

Workflow

1. Build the installer for the container platform
2. Start a fresh container
3. Run the installer inside it
4. Verify results
5. Stop the container
6. Repeat for each distro (ubuntu, debian, fedora)

Step 1: Build the Binary

Use goreleaser to build snapshot binaries for all platforms defined in .goreleaser.yaml. Run from the installer/ directory:

cd installer && goreleaser build --skip before --snapshot --clean

This produces binaries under installer/dist/, one per OS-arch combo. The docker-compose volumes mount installer/ into containers at /workspace/installer, so the binary path inside the container follows this pattern:

/workspace/installer/dist/dotfiles_installer_<os>_<arch>/dotfiles-installer

For example, on a macOS ARM host (Apple Silicon) running Linux ARM64 containers:

/workspace/installer/dist/dotfiles_installer_linux_arm64_v8.0/dotfiles-installer

For Linux AMD64 containers:

/workspace/installer/dist/dotfiles_installer_linux_amd64_v1/dotfiles-installer

Step 2: Run Tests in Containers

Start a fresh container for each test scenario to avoid state leakage from previous runs. Reuse the image, but always start from scratch.

cd installer/docker

# Start container
task ubuntu:start

# Run the installer (adjust flags for the scenario being tested)
docker-compose -f ubuntu/docker-compose.yml exec --user testuser installer-test-ubuntu \
  sudo /workspace/installer/dist/dotfiles_installer_linux_arm64_v8.0/dotfiles-installer install \
    --shell zsh --shell-source auto --non-interactive --install-prerequisites

# Verify results (scenario-dependent)
# ...

# Tear down before next test
task ubuntu:stop

For standalone containers (without docker-compose), bind-mount the dist directory explicitly:

docker run -d --name test-ubuntu --platform linux/arm64 \
  -v "$(pwd)/../dist:/workspace/installer/dist:ro" \
  ubuntu-installer-test-ubuntu:latest tail -f /dev/null

docker exec test-ubuntu /workspace/installer/dist/dotfiles_installer_linux_arm64_v8.0/dotfiles-installer install \
  --shell zsh --shell-source system --non-interactive

docker stop test-ubuntu && docker rm test-ubuntu

Step 3: Verify Results

Verification depends on what the test scenario is exercising. After running the installer, determine appropriate checks based on the flags and features being tested, then run them inside the container using docker-compose exec or docker exec.

Testing All Distros

Run through all three distros. Always stop before starting the next test:

cd installer/docker

for distro in ubuntu debian fedora; do
  task ${distro}:start
  # ... run installer and verify ...
  task ${distro}:stop
done

Interactive GPG Testing

For testing the GPG key setup flow interactively (which requires automating GPG's prompts), see the testing-interactive-gpg skill.

Gotchas

• See distro-specific notes for platform quirks (zsh paths, brew behavior, package manager differences)
• Homebrew's first run downloads portable Ruby (~30MB) and can take several minutes
• Fedora's first dnf triggers a repo metadata sync (~30MB) - be patient or use generous timeouts
• If brew errors with "process has already locked", a previous install was interrupted - start a fresh container
• When running long tests, prefer running in background and polling for completion over setting very long timeouts