Class: Mutineer::CLI

Inherits:
Object
  • Object
show all
Defined in:
lib/mutineer/cli.rb

Overview

Command-line entry point. start is the single public method called by bin/mutineer; it parses argv, acts, and exits with a pinned code.

Exit codes (taxonomy consistent across M1–M5):

0  success / requested output (--version, --help, score >= threshold)
1  survivors below threshold, or a runtime error
2  usage / flag error (unknown subcommand, invalid flag, unknown operator,
 out-of-range threshold)

Constant Summary collapse 

<<~USAGE
  Usage: mutineer [options] <command> [args]

  Commands:
    run [options] <source...> --test <test...>   Mutate, run, and report
    run --dry-run [options] <source...>          Print candidate mutations only

  Run options:
    --test FILE          Test file covering the sources (repeatable)
    --operators LIST     Comma-separated operator names (default: Tier 1 set)
    --threshold FLOAT    Fail (exit 1) when score < FLOAT (default: 0 = off)
    --baseline FILE      Fail (exit 1) on NEW survivors / score drop vs a prior
                         --format json run (CI delta gate)
    --baseline-epsilon FLOAT  Score-drop tolerance for --baseline (default: 0)
    --only NAME          Restrict to one fully-qualified subject
    --since REF          Only mutate lines changed since git REF (e.g. origin/main)
    --jobs N             Parallel worker count (default: processor count)
    --strategy NAME      reload (whole-file) or redefine (surgical); default: reload
    --framework NAME     minitest or rspec (default: auto-detect from --test names)
    --boot FILE          Require FILE once in the parent to boot the app env, then
                         fork per mutant (Rails apps; requires --test)
    --rails              Sugar for --boot config/environment --strategy redefine
    --test-command CMD   Run the target suite in the app's own runtime as a
                         subprocess (for apps on Ruby < 3.4). CMD must contain
                         %{files} (expands to the --test paths). Env is inherited,
                         e.g. RAILS_ENV=test mutineer run ... --test-command "..."
    --daemon             Boot the app ONCE in a persistent daemon and fork per
                         mutant, with per-worker DB isolation so --jobs N is safe
                         under Rails (needs --rails/--boot; not with --test-command)
    --format human|json|html  Report format (default: human)
    --output FILE        Write the report to FILE instead of stdout
    --dry-run            List mutations without executing
    --fail-fast          Stop at the first surviving mutant
    --verbose            Surface the real error when a fork capture fails (alias: --debug)

  Options:
    --list-operators  List available operators (default vs optional) and exit
    --version         Print version and exit
    --help            Print this help and exit
USAGE
PRECEDENCE_FLAGS =

Field symbols whose config-file value is suppressed when the flag is typed.

%i[operators jobs threshold only].freeze
STRATEGY_ALIASES =

Deprecated internal strategy names, mapped to their canonical equivalents.

{ "7a" => "reload", "7b" => "redefine" }.freeze

Class Method Summary collapse

Class Method Details

.autopair!(config, explicit) ⇒ void

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future.

This method returns an undefined value.

#11: auto-pair sources to tests by path convention when no --test was given (explicit --test wins — R5). Each source with an inferred test on disk joins the run; a source with none is dropped with a one-line stderr warning (R3) and the run continues with the rest. If every source is dropped: in boot mode the dedicated --boot/--rails-requires-test check reports it; otherwise exit 2 with a usage message. The framework is re-detected from the inferred set unless it was set explicitly (a spec-only project loads/reports as rspec). Auto-pairs sources and tests when --test is absent.

Parameters:

  • config (Mutineer::Config) —

    run configuration.

  • explicit (Set<Symbol>) —

    explicit CLI fields.



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# File 'lib/mutineer/cli.rb', line 389

def self.autopair!(config, explicit)
  return unless config.tests.empty?

  paired = config.sources.filter_map do |s|
    t = Pairing.infer_test(s, project_root: config.project_root, prefer: config.framework)
    [s, t] if t
  end
  (config.sources - paired.map(&:first)).each do |s|
    warn "[mutineer] no test found by convention for #{s}; skipping"
  end
  config.sources = paired.map(&:first)
  config.tests   = paired.map(&:last).uniq
  config.framework = Config.detect_framework(config.tests) unless explicit.include?(:framework)

  return unless config.sources.empty?
  return if config.boot # let the --boot/--rails-requires-test check report it

  warn "mutineer: no test files found by convention; pass --test or add tests"
  exit 2
end

.dry_run(config) ⇒ void

This method returns an undefined value.

Runs dry-run mode.

Parameters:



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# File 'lib/mutineer/cli.rb', line 511

def self.dry_run(config)
  operator_classes = MutatorRegistry.resolve(config.operators || MutatorRegistry::DEFAULT_NAMES)
  sources = {}
  per_operator = Hash.new(0)
  skipped = 0
  ignored = 0
  ignore_set = config.ignore.to_set

  # --since narrows the preview to changed lines too, so `--dry-run --since`
  # shows exactly what a real `--since` run would mutate.
  changed = if config.since
              ChangedLines.for(ref: config.since, files: config.sources,
                               project_root: config.project_root)
            end

  Project.discover(config.sources, only: config.only).each do |subject|
    source = (sources[subject.file] ||= Parser.parse_file(subject.file).source.source)
    # #22: honor suppression so the preview matches what a real run mutates.
    # Mirror execute's per-subject shape (ids need the full mutation list).
    disabled = Runner.suppress_map(source)
    mutations = operator_classes.flat_map { |klass| klass.new.mutations_for(subject, source) }
    ids = MutantId.for_subject(subject, source, mutations)
    mutations.each_with_index do |mutation, i|
      unless mutation.valid?(source)
        skipped += 1
        next
      end
      line = source.byteslice(0, mutation.start_offset).count("\n") + 1
      next if changed && !changed[File.expand_path(subject.file, config.project_root)]&.include?(line)

      if Runner.suppressed?(mutation.operator, line, ids[i], disabled, ignore_set)
        ignored += 1
        next
      end

      per_operator[mutation.operator] += 1
      original = source.byteslice(mutation.start_offset...mutation.end_offset)
      puts "[#{mutation.operator}] #{subject.qualified_name}  " \
           "#{subject.file}:#{line}  `#{original}` -> `#{mutation.replacement}`"
    end
  end

  total = per_operator.values.sum
  breakdown = per_operator.map { |op, n| "#{op}: #{n}" }.join(", ")
  summary = breakdown.empty? ? "" : "#{breakdown} — "
  puts "#{summary}#{total} mutations (dry run, not executed); " \
       "#{skipped} skipped (invalid); #{ignored} ignored (suppressed)"
  exit 0
end

.execute(config) ⇒ void

This method returns an undefined value.

Executes the run command.

Parameters:



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# File 'lib/mutineer/cli.rb', line 444

def self.execute(config)
  if config.tests.empty?
    warn "mutineer: run requires at least one --test file (or use --dry-run)"
    exit 2
  end

  aggregate, source_map = Runner.execute(config)
  reporter = Reporter.new(aggregate, source_map)

  # #13: diff the current run against the baseline (preflighted above) by the
  # stable survivor id. The delta is rendered inline (human section / additive
  # json block) and gates exit independently of --threshold.
  delta = (Baseline.load(config.baseline).diff(aggregate, epsilon: config.baseline_epsilon) if config.baseline)

  reporter.report(out: $stdout, err: $stderr, threshold: config.threshold,
                  format: config.format, output: config.output, baseline: delta)

  # #27/KTD-6: warn (stderr, so it never pollutes json/html) that an external
  # run's score is not comparable to an in-process run — it has no coverage
  # narrowing, so uncovered mutants count as survivors, and an infra failure is
  # scored as a kill (upper bound).
  if config.test_command
    warn "[mutineer] --test-command score is an upper bound, not comparable to an " \
         "in-process run: no coverage narrowing (uncovered mutants count as survivors) " \
         "and an infra failure is scored as a kill."
  end

  # #26/U8: same disclosure as --test-command above — the daemon backend has no
  # coverage narrowing yet (Phase 2c), so this score is a lower bound (uncovered
  # mutants count as survivors) and not comparable to an in-process run.
  if config.daemon
    warn "[mutineer] --daemon score is a lower bound, not comparable to an " \
         "in-process run: no coverage narrowing yet (uncovered mutants count as " \
         "survivors)."
  end

  # #14: nudge toward the opt-in tier-2 operators (human report only — never
  # pollute JSON output).
  if !%w[json html].include?(config.format) && (hint = tier2_hint(config.operators))
    puts hint
  end

  # #13/KTD-4: --baseline and --threshold are independent gates OR'd together.
  # `max` of two 0/1 codes is the OR; usage (2) is handled earlier and wins.
  baseline_exit = delta&.regressed ? 1 : 0
  exit [reporter.exit_code(threshold: config.threshold), baseline_exit].max
end

.list_operators ⇒ void

This method returns an undefined value.

Lists available operators.



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# File 'lib/mutineer/cli.rb', line 166

def self.list_operators
  MutatorRegistry::ALL.each_key do |name|
    state = MutatorRegistry.default?(name) ? "default" : "disabled"
    puts format("%-20s tier %d  %-9s %s",
                name, MutatorRegistry.tier(name), state, MutatorRegistry::DESCRIPTIONS[name])
  end
end

.preflight_baseline!(path) ⇒ void

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future.

This method returns an undefined value.

#13: a missing/unreadable/unparseable baseline is a usage error (exit 2), mirroring --output/--since preflight, so CI sees "bad invocation," not a backtrace mid-run. Validating up front = attempting the load (it raises ConfigError/SystemCallError; the actual diff reloads in execute). Preflights a baseline file.

Parameters:

  • path (String) —

    baseline file path.



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# File 'lib/mutineer/cli.rb', line 419

def self.preflight_baseline!(path)
  Baseline.load(path)
rescue Mutineer::ConfigError, SystemCallError => e
  warn "mutineer: #{e.message}"
  exit 2
end

.preflight_output!(path) ⇒ void

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future.

This method returns an undefined value.

Preflights an output path.

Parameters:

  • path (String) —

    output file path.



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# File 'lib/mutineer/cli.rb', line 431

def self.preflight_output!(path)
  dir = File.dirname(File.expand_path(path))
  return if File.directory?(dir) && File.writable?(dir)

  reason = File.directory?(dir) ? "directory is not writable" : "no such directory"
  warn "mutineer: cannot write to #{path}: #{reason}"
  exit 2
end

.run(config, explicit = Set.new) ⇒ void

This method returns an undefined value.

Runs the requested command after validation.

Parameters:

  • config (Mutineer::Config) —

    run configuration.

  • explicit (Set<Symbol>) (defaults to: Set.new) —

    explicit CLI fields.



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# File 'lib/mutineer/cli.rb', line 179

def self.run(config, explicit = Set.new)
  if config.sources.empty?
    warn "mutineer: run requires at least one source file"
    exit 2
  end
  validate!(config, explicit)

  config.dry_run ? dry_run(config) : execute(config)
rescue ArgumentError => e
  # Unknown --operators value surfaces here; no backtrace reaches the user.
  warn "mutineer: #{e.message}"
  exit 2
rescue SystemCallError => e
  # R5: a missing/unreadable path reaches here as Errno::ENOENT etc. — a plain
  # message and usage exit, never a raw backtrace.
  warn "mutineer: #{e.message}"
  exit 2
rescue SyntaxError => e
  # A syntactically invalid source file surfaces when `require`d; report it
  # cleanly rather than dumping a backtrace.
  warn "mutineer: cannot load source: #{e.message}"
  exit 1
rescue Mutineer::ParseError => e
  warn "mutineer: error reading: #{e.message}"
  exit 1
rescue Mutineer::SmokeCheckError => e
  # #27: the unmutated suite isn't green under --test-command — a broken
  # environment, not weak tests. Runtime error (exit 1), not usage (exit 2).
  warn "mutineer: #{e.message}"
  exit 1
end

.start(argv) ⇒ void

This method returns an undefined value.

Parses arguments, executes the command, and exits.

Parameters:

  • argv (Array<String>) —

    raw command-line arguments.



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# File 'lib/mutineer/cli.rb', line 79

def self.start(argv)
  opts = {}            # symbol => value, the CLI-provided Config fields
  explicit = Set.new   # precedence keys the user typed (KTD3)
  show_operators = false

  parser = OptionParser.new do |o|
    o.banner = BANNER
    o.on("--version") do
      puts Mutineer::VERSION
      exit 0
    end
    o.on("--help") do
      puts BANNER
      exit 0
    end
    o.on("--list-operators") { show_operators = true }
    o.on("--dry-run") { opts[:dry_run] = true }
    o.on("--fail-fast") { opts[:fail_fast] = true }
    o.on("--only NAME") { |v| opts[:only] = v; explicit << :only }
    o.on("--since REF") { |v| opts[:since] = v; explicit << :since }
    o.on("--test FILE") { |v| (opts[:tests] ||= []) << v }
    o.on("--operators LIST") { |v| opts[:operators] = v.split(",").map(&:strip); explicit << :operators }
    o.on("--threshold FLOAT") { |v| opts[:threshold] = v.to_f; explicit << :threshold }
    o.on("--jobs N") { |v| opts[:jobs] = v; explicit << :jobs }
    o.on("--strategy STRAT") { |v| opts[:strategy] = v; explicit << :strategy }
    o.on("--framework NAME") { |v| opts[:framework] = v; explicit << :framework }
    o.on("--boot FILE") { |v| opts[:boot] = v; explicit << :boot }
    o.on("--rails") { opts[:rails] = true }
    o.on("--verbose") { opts[:verbose] = true }
    o.on("--debug") { opts[:verbose] = true } # alias of --verbose
    o.on("--format FORMAT") { |v| opts[:format] = v }
    o.on("--output FILE") { |v| opts[:output] = v }
    # #13: --baseline is also a .mutineer.yml key, so mark it explicit when
    # typed (CLI wins over the file). --baseline-epsilon is CLI-only.
    o.on("--baseline FILE") { |v| opts[:baseline] = v; explicit << :baseline }
    o.on("--baseline-epsilon FLOAT") { |v| opts[:baseline_epsilon] = v.to_f }
    # #27: run the target suite as a subprocess in the app's OWN runtime so
    # mutineer (Ruby >= 3.4) can mutation-test apps pinned to an older Ruby.
    o.on("--test-command CMD") { |v| opts[:test_command] = v; explicit << :test_command }
    # #26/#27 Phase 2: boot the app ONCE in a persistent daemon and fork per
    # mutant, with per-worker DB isolation so --jobs N is safe under Rails.
    o.on("--daemon") { opts[:daemon] = true; explicit << :daemon }
  end

  begin
    parser.parse!(argv)
  rescue OptionParser::InvalidOption, OptionParser::MissingArgument => e
    warn "mutineer: #{e.message}"
    exit 2
  end

  if show_operators
    list_operators
    exit 0
  end

  if argv.empty?
    puts BANNER
    exit 0
  end

  begin
    file_path = Config.find_file
    file_hash = file_path ? Config.from_file(file_path) : {}
    config = Config.resolve(opts, file_hash, explicit)
  rescue Mutineer::ConfigError => e
    # R8: the lib layer raises instead of killing the host; the CLI maps a
    # config (usage) error to exit 2.
    warn "mutineer: #{e.message}"
    exit 2
  end

  case argv.first
  when "run"
    # #11: a directory source expands to its **/*.rb files; literal files pass
    # through. Test inference (when --test is omitted) happens in validate!.
    config.sources = Pairing.expand_sources(argv[1..], project_root: config.project_root)
    run(config, explicit)
  else
    warn "mutineer: unknown command '#{argv.first}'"
    exit 2
  end
end

.tier2_hint(active) ⇒ String?

The tier-2 operators not in the active set, as a one-line hint (or nil when they're all already enabled). active nil means the default (Tier-1) set. Builds a Tier-2 operator hint.

Parameters:

  • active (Array<String>, nil) —

    active operator names.

Returns:

  • (String, nil) —

    hint text or nil.



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# File 'lib/mutineer/cli.rb', line 498

def self.tier2_hint(active)
  active ||= MutatorRegistry::DEFAULT_NAMES
  unused = MutatorRegistry::TIER2_NAMES - active
  return if unused.empty?

  "#{unused.size} tier-2 operators available (#{unused.join(', ')}) — " \
    "enable with --operators <list>."
end

.validate!(config, explicit = Set.new) ⇒ void

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future.

This method returns an undefined value.

Flag validation: every flag/usage failure exits 2 (C7), consistent with the taxonomy above — CI can tell "mistyped flag" from "tests too weak." Validates the run configuration.

Parameters:

  • config (Mutineer::Config) —

    run configuration.

  • explicit (Set<Symbol>) (defaults to: Set.new) —

    explicit CLI fields.



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# File 'lib/mutineer/cli.rb', line 219

def self.validate!(config, explicit = Set.new)
  unless (0.0..100.0).cover?(config.threshold)
    warn "mutineer: --threshold must be between 0 and 100"
    exit 2
  end

  jobs = Integer(config.jobs.to_s, exception: false)
  if jobs.nil? || jobs < 1
    warn "mutineer: --jobs requires a positive integer (got: #{config.jobs})"
    exit 2
  end
  config.jobs = jobs

  unless %w[human json html].include?(config.format)
    warn %(mutineer: unknown format "#{config.format}". Expected: human, json, html)
    exit 2
  end

  # Canonical strategies are reload|redefine; 7a/7b are accepted as deprecated
  # aliases. Normalize to canonical so the rest of the pipeline sees one name.
  config.strategy = STRATEGY_ALIASES.fetch(config.strategy, config.strategy)
  unless %w[reload redefine].include?(config.strategy)
    warn %(mutineer: unknown strategy "#{config.strategy}". Expected: reload, redefine)
    exit 2
  end

  unless %w[minitest rspec].include?(config.framework)
    warn %(mutineer: unknown framework "#{config.framework}". Expected: minitest, rspec)
    exit 2
  end

  validate_test_command!(config) if config.test_command
  validate_daemon!(config, explicit) if config.daemon

  validate_since!(config) if config.since
  preflight_output!(config.output) if config.output
  preflight_baseline!(config.baseline) if config.baseline

  # #11: when --test is omitted, infer each source's test by convention so the
  # boot-once/fork-per-test core (which pairs empirically by coverage) gets a
  # populated config.tests. Runs after every flag/usage check above so a
  # mistyped flag still reports the flag; skipped under --dry-run (no tests
  # needed). validate_paths! then sees the inferred (real) tests.
  autopair!(config, explicit) unless config.dry_run

  # Boot mode does no coverage selection — every mutant runs the given tests —
  # so at least one --test file is mandatory (there is nothing to select from).
  if config.boot && config.tests.empty?
    warn "mutineer: --boot/--rails requires at least one --test file"
    exit 2
  end

  validate_paths!(config)
end

.validate_daemon!(config, _explicit = Set.new) ⇒ void

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future.

This method returns an undefined value.

#26/#27 Phase 2 (U8): --daemon selects the persistent-daemon backend (boot once, fork per mutant, per-worker DB isolation). Two usage errors, both exit 2 (KTD-10): it cannot be combined with --test-command (choose ONE backend — never silently pick one), and it requires an app to boot (--rails or --boot). Under Rails, Config.resolve already keeps --jobs serial unless the user explicitly asks for parallelism, and each worker gets its own SQLite database on demand — so there is no "missing worker DB" precondition to check here for SQLite. Postgres worker-DB provisioning + its missing-DB error (KTD-9) arrives with the Postgres adapter (U10).

Parameters:

  • config (Mutineer::Config) —

    run configuration.

  • explicit (Set<Symbol>) —

    explicit CLI fields.



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# File 'lib/mutineer/cli.rb', line 323

def self.validate_daemon!(config, _explicit = Set.new)
  if config.test_command
    warn "mutineer: choose one backend — --daemon and --test-command cannot be combined"
    exit 2
  end
  return if config.rails || config.boot

  warn "mutineer: --daemon needs an app to boot; add --rails (or --boot FILE)"
  exit 2
end

.validate_paths!(config) ⇒ void

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future.

This method returns an undefined value.

R5: validate path existence up front so a typo is a clean usage error (exit 2), not an Errno::ENOENT backtrace from deep in the run. Flag checks run first so a bad flag still reports the flag, not the missing file. Validates source and test paths.

Parameters:



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# File 'lib/mutineer/cli.rb', line 367

def self.validate_paths!(config)
  missing = (config.sources + config.tests)
            .reject { |p| File.exist?(File.expand_path(p, config.project_root)) }
  return if missing.empty?

  warn "mutineer: no such file: #{missing.join(', ')}"
  exit 2
end

.validate_since!(config) ⇒ void

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future.

This method returns an undefined value.

--since needs a real git repo and a resolvable ref; either failure is a usage error (exit 2) so CI sees "bad invocation," not "tests too weak." Validates the --since ref.

Parameters:



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# File 'lib/mutineer/cli.rb', line 341

def self.validate_since!(config)
  _out, _err, status = Open3.capture3(
    "git", "-C", config.project_root, "rev-parse", "--verify", "--quiet",
    "#{config.since}^{commit}"
  )
  return if status.success?

  inside, = Open3.capture3(
    "git", "-C", config.project_root, "rev-parse", "--is-inside-work-tree"
  )
  msg = inside.strip == "true" ? "unknown git ref: #{config.since}" : "--since requires a git repository"
  warn "mutineer: #{msg}"
  exit 2
rescue Errno::ENOENT
  warn "mutineer: --since requires git on PATH"
  exit 2
end

.validate_test_command!(config) ⇒ void

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future.

This method returns an undefined value.

#27: --test-command runs the target suite in the app's own runtime. Validate its shape up front (usage errors → exit 2) and force serial execution: each subprocess boots the app and opens its own fixture transaction against the same DB, so --jobs > 1 would corrupt results (the #12 fixture-contention hazard). Unlike --rails, this path has NO per-worker DB isolation to opt into, so an explicit --jobs N is forced to 1 rather than honored (KTD-5). Validates the --test-command configuration.

Parameters:



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# File 'lib/mutineer/cli.rb', line 285

def self.validate_test_command!(config)
  if config.test_command.strip.empty?
    warn "mutineer: --test-command must not be empty"
    exit 2
  end
  unless config.test_command.include?("%{files}")
    warn "mutineer: --test-command must contain %{files} (where the --test paths are substituted)"
    exit 2
  end
  if config.boot
    warn "mutineer: --test-command cannot be combined with --boot/--rails " \
         "(the external subprocess boots the app itself)"
    exit 2
  end
  if config.strategy == "redefine"
    warn "mutineer: --test-command supports only --strategy reload " \
         "(surgical redefine needs a shared VM; the subprocess has its own)"
    exit 2
  end
  return unless config.jobs > 1

  warn "[mutineer] --test-command runs serially (no per-worker DB isolation yet); forcing --jobs 1."
  config.jobs = 1
end