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refactor-command-to-commandlineresult

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Migrates a command class that still performs parsing or custom execution logic to return raw Git::CommandLineResult, moving parsing to facade/parser layers. Use during architectural redesign refactoring.

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Refactor Command to CommandLineResult

Migrate a command that still performs parsing or custom execution logic to the Git::Commands::Base pattern, so command classes return raw Git::CommandLineResult and parsing moves to facade/parser layers.

Contents

How to use this skill

Attach this file to your Copilot Chat context, then invoke it with the command class or source file to migrate. Examples:

Using the Refactor Command to CommandLineResult skill, migrate
Git::Commands::Stash::Pop to the Base pattern.
Refactor Command to CommandLineResult: lib/git/commands/branch/delete.rb

The invocation needs the command class name or file path of the command to refactor.

Prerequisites

Before starting, you MUST load the following skill(s) in their entirety:

  • YARD Documentation — authoritative source for YARD formatting rules and writing standards;

Related skills

Target end state

class SomeCommand < Git::Commands::Base
  arguments do
    ...
  end

  # optional for non-zero successful exits
  # rationale comment
  # allow_exit_status 0..1

  # @!method call(*, **)
  #
  #   @overload call(**options)
  #
  #     Execute the git ... command.
  #
  #     @return [Git::CommandLineResult]
end

Refactor steps

  1. Move parsing/transforming logic out of command class into caller/facade/parser.
  2. Replace legacy ARGS constant + custom initialize with arguments do + inheritance from Base.
  3. Remove custom #call body and add # @!method call(*, **) YARD directive.
  4. If command requires non-default success exits, add allow_exit_status with rationale comment.
  5. Update callers to consume CommandLineResult and parse result.stdout where needed.

What to remove from command classes

  • parser invocations
  • output transformation logic
  • literal entries for policy/output-control flags (e.g. literal '--no-edit', literal '--verbose', literal '--no-progress', literal '--no-color') — command classes are neutral, faithful representations of the git CLI; convert to flag_option / value_option so the facade can pass the policy value. See "Command-layer neutrality" in CONTRIBUTING.md.
  • manual raise_on_failure / manual exit-code checks (unless temporarily needed in an unmigrated class)
  • duplicated bind/execute logic

What to update in tests

  • unit specs should assert CLI args and CommandLineResult behavior
  • remove parsed-object assertions from command unit specs
  • move parsing expectations to parser/facade tests
  • include raise_on_failure: false in mocked command expectations

YARD updates

  • update @return to Git::CommandLineResult
  • keep command-specific @overload docs nested under # @!method call(*, **) directive
  • ensure @raise wording reflects allowed range behavior
  • tag short descriptions must not end with punctuation (no trailing period, comma, or colon)
  • multi-paragraph tag descriptions must have a blank comment line (#) between the short description and each continuation paragraph

Migration process and internal compatibility

See Command Implementation for the canonical phased rollout checklist and internal compatibility contract. In summary:

  • always work on a feature branch — never commit or push directly to main; create a branch before starting (git checkout -b <feature-branch-name>) and open a pull request when the slice is ready
  • perform refactor in phased slices (pilot/family)
  • keep each slice independently revertible
  • do not mix unrelated behavior changes with refactor-only changes
  • pass slice gates: bundle exec rspec, bundle exec rake test, bundle exec rubocop, bundle exec rake yard