Testing and Linting

Testing and Linting

Running them

bundle exec rspec     # unit tests
bundle exec rubocop   # style/lint
bundle exec rake      # both — the default task

rake with no arguments runs spec then rubocop. CI runs them as separate steps (rake spec, rake rubocop) so a failure names which one.

Useful during development:

bundle exec rspec spec/wip/config_spec.rb
bundle exec rspec spec/wip/config_spec.rb:42
bundle exec rspec --only-failures
bundle exec rubocop -a          # safe autocorrect
bundle exec rubocop -A          # includes unsafe autocorrect — review the diff

No WSLC required

The suite runs on any platform. Every layer that would touch the outside world is injectable:

Class	Injection point
CommandResolver	executable: — a callable deciding whether a candidate exists
CommandResolver	path: — the PATH string to search
CommandBuilder	wslc:, config:, environment:, dotenv: — and it only builds arrays
CommandRunner	stdin: / stdout: / stderr: — StringIO in tests
CommandRunner	interpreter: — a stub ErrorInterpreter
Doctor	loader:, resolver:, environment:, compose_resolver:
Environment	stdin: / stdout: for TTY detection
DebugReporter / ResourceMonitor / StagingProgress	out:

Keep it that way. A change that hardcodes a real filesystem path, a real PATH lookup, or a real spawn makes that code untestable on CI.

Where a test belongs

One spec file per class, mirroring lib/:

lib/wip/config.rb          →  spec/wip/config_spec.rb
lib/wip/compose_file.rb    →  spec/wip/compose_file_spec.rb
lib/wip/command_builder.rb →  spec/wip/command_builder_spec.rb

Test at the layer that owns the behavior:

Behavior	Spec
A validation rule / a ConfigError	config_spec.rb, sync_settings_spec.rb, compose_file_spec.rb
The exact wslc arguments produced	command_builder_spec.rb, compose_bridge_spec.rb
A diagnostic's level and message	doctor_spec.rb
Flag parsing, command wiring, orchestration order	cli_spec.rb
.dockerignore matching, staging, shadow sync	docker_ignore_spec.rb, build_context_spec.rb

Prefer the narrowest layer. A new wip.yml rule is a config_spec.rb test, not an end-to-end CLI test that happens to exercise it.

What a good test asserts

For command construction — the exact array:

expect(builder.exec(['bin/rails', 'c'], interactive: true)).to eq(
  ['wslc.exe', 'exec', '-it', '-w', '/app', '-e', 'RAILS_ENV=development', 'app', 'bin/rails', 'c']
)

Arrays, not joined strings — the array is the injection-safety guarantee.

For validation — the message, not just the class:

expect { described_class.new(raw) }
  .to raise_error(Wip::ConfigError, /container: must be set when dependencies: has entries/)

Every ConfigError in this codebase names the offending key. Asserting on the message keeps that property from eroding.

For defaults — assert the default explicitly, so a change to it is a visible test failure.

RuboCop configuration

.rubocop.yml:

Setting	Value
TargetRubyVersion	3.2
NewCops	enabled
Layout/LineLength	120
Metrics/MethodLength	20
Metrics/AbcSize	25
Metrics/ClassLength	160, waived for cli.rb, compose_file.rb, config.rb
Metrics/BlockLength	waived for spec/**/*

Every file starts with # frozen_string_literal: true.

The three class-length exemptions are acknowledged debt, not permission to keep growing those files. Prefer extracting a collaborator over widening the waiver.

Inline disables

Occasionally necessary — with a reason:

file = File.open(path, 'a') # rubocop:disable Style/FileOpen -- closed by `step`'s ensure block

A bare rubocop:disable with no explanation will get a review comment.

The CI matrix

.github/workflows/test.yml, on every PR and every push to main:

• Ruby 3.2, 3.3, 3.4, 4.0 (fail-fast: false)
• bundle exec rake spec
• bundle exec rake rubocop
• CLI smoke test: bundle exec exe/wip help | grep -q '^Commands:'

The smoke test is a cheap guard against a change that breaks the executable while every unit test still passes.

Before opening a PR

bundle exec rake

Clean output, on the oldest supported Ruby if you can — 3.2 is the target version, and syntax newer than that will pass locally on 3.4 and fail in CI.

Related

• Development
• Architecture