Skip to content

ruby.md

Latest commit

 

History

History
328 lines (239 loc) · 12.9 KB

ruby.md

File metadata and controls

328 lines (239 loc) · 12.9 KB

Ruby

Quick Reference

Tool AI-Friendly Flags
bundle install --quiet
rake -s (silent — suppresses rake's own messages, only shows task output)
rspec --format progress --no-color --fail-fast
minitest -q (no dots) or -v (test names, no color by default)
rails test --no-color --fail-fast
rubocop --format emacs --no-color (one-line-per-offense)
rubocop (fix) -A --no-color (safe + unsafe autocorrect)
standard --format emacs --no-color (or --format quiet for silent-when-clean)
standard (fix) --fix --no-color
srb tc --color never --no-error-count --no-error-sections
reek --no-color --no-progress -s
brakeman -q --no-progress --no-pager --no-color
rails generate --quiet --force (suppresses status lines, prevents prompts)
rails db:migrate VERBOSE=false (suppresses migration output)
erb_lint -f compact (or -f json for structured output)

bundle

# Quiet install (warnings and errors only)
bundle install --quiet

# Verbose but clean (parallel, retries)
bundle install --jobs=4 --retry=3
  • --quiet — suppresses progress output, only shows warnings and errors
  • --jobs=N / -jN — parallel gem downloads/installs
  • --retry=N — retry failed network requests (default: 3)
  • --local — use only locally cached gems, skip all network requests

bundle update and bundle add also accept --quiet.

Bundler auto-detects non-TTY and disables colors when stdout is not a terminal. The --no-color global flag is available on all bundle subcommands as a safety net.

Env var equivalents: NO_COLOR=1 (disables color), BUNDLE_JOBS=4, BUNDLE_RETRY=3, BUNDLE_IGNORE_MESSAGES=true (suppresses post-install messages).

rake

# Silent — only shows output from the task itself
rake -s taskname

# Quiet — suppresses rake's own logging
rake -q taskname
  • -s / --silent — suppresses rake's own messages including "in directory" announcements
  • -q / --quiet — suppresses rake's log messages but keeps directory announcements
  • -t / --trace — shows full backtrace on error (trace output goes to stderr by default)

Rake itself produces no colored output — any colors come from the tasks being run (test frameworks, linters, etc.).

rspec

# Compact output (default dots, no color)
rspec --format progress --no-color

# One line per failure (most token-efficient for failures)
rspec --format failures --no-color --fail-fast

# Structured JSON output
rspec --format json --no-color
  • --format progress — default: dots for pass, F for fail, * for pending
  • --format failures — one line per failure: spec/foo_spec.rb:42:should do something (extremely compact)
  • --format json — full structured JSON with test details, timing, and exception info
  • --format documentation — nested describe/it names (verbose but readable)
  • --no-color — disables ANSI color codes
  • --fail-fast — stop after first failure (or --fail-fast=N after N failures)
  • --order defined — deterministic run order

Single test: rspec spec/models/user_spec.rb:42 or rspec -e "validates email"

RSpec auto-detects non-TTY and disables color by default, unless --color is set in .rspec. --no-color overrides all.

Env var: SPEC_OPTS="--format json --no-color --fail-fast" injects options on every run without modifying project config.

Other formatters: html. No --quiet flag — use --format failures for minimal output.

minitest

# Quiet (no progress dots)
ruby -Ilib:test test/my_test.rb -q

# Verbose (each test name printed)
ruby -Ilib:test test/my_test.rb -v

# Via rake
rake test
  • -q / --quiet — suppresses progress dots
  • -v / --verbose — prints each test name as it runs
  • -n PATTERN / --include — run specific test: -n test_something or -n /regex/
  • -s SEED / --seed — set random seed for ordering

Minitest has no color by default. The bundled pride plugin (-p) or the minitest-reporters gem add color — both auto-detect TTY and disable color when piped.

For structured output, use the minitest-reporters gem with JUnitReporter for XML.

Env vars: A="--verbose" passes options through rake test when using Minitest::TestTask (the older Rake::TestTask still uses TESTOPTS).

rails test

# Minimal output
bin/rails test --no-color --fail-fast

# Single test by file and line
bin/rails test test/models/user_test.rb:42 --no-color --fail-fast

# Deferred output (failures printed after full run)
bin/rails test --no-color --fail-fast -d
  • --no-color — disables ANSI colors
  • --fail-fast / -f — stop after first failure
  • -d / --defer-output — collects failures, prints them after the run completes
  • -v / --verbose — shows per-test names and timing
  • -b / --backtrace — shows full unfiltered backtrace (verbose, use selectively)
  • -n PATTERN / --include — filter tests by name

Rails auto-detects non-TTY and disables color when output is piped.

rails generate

bin/rails generate model User name:string --quiet --force
  • -q / --quiet — suppresses all "create", "invoke" status lines
  • -f / --force — overwrites existing files without prompting (prevents hanging)
  • --skip-collision-check — skips class-name collision checking (file collisions are handled by --force)

Without --quiet, generators print a status line for every file created or modified.

rails db:migrate

VERBOSE=false bin/rails db:migrate
  • VERBOSE=false — suppresses all migration output (create_table, add_column, etc.)
  • --trace — shows full rake task chain and backtrace on error

There is no --quiet flag for migrations — use the VERBOSE env var.

rubocop

# One-line-per-offense (most token-efficient text format)
rubocop --format emacs --no-color

# Structured JSON output
rubocop --format json --no-color

# Silent when clean, simple format when offenses found
rubocop --format quiet --no-color

# Auto-fix (safe corrections only)
rubocop -a --no-color

# Auto-fix (safe + unsafe corrections)
rubocop -A --no-color
  • --format emacs — file:line:col: severity: message (one line per offense, easily parseable)
  • --format json — full structured JSON with metadata, offenses, and summary
  • --format quiet — silent when clean, simple format when offenses exist
  • --format offenses — violation counts per cop (overview)
  • --no-color — disables ANSI colors
  • -a / --autocorrect — safe corrections only
  • -A / --autocorrect-all — safe and unsafe corrections
  • --display-only-fail-level-offenses — only show offenses at or above --fail-level
  • --fail-level SEVERITY — minimum severity for non-zero exit (A, I, R, C, W, E, F)
  • -F / --fail-fast — stop after first file with offenses

RuboCop auto-detects non-TTY via the Rainbow gem and disables color when piped.

Env var: RUBOCOP_OPTS="--format emacs --no-color" injects options on every run.

Other formatters: simple, clang (with source context), progress (default), tap, junit, markdown, github, html, files, worst, fuubar, pacman, autogenconf.

standard

# One-line-per-offense
standardrb --format emacs --no-color

# Silent when clean
standardrb --format quiet --no-color

# Auto-fix (safe)
standardrb --fix --no-color

# Auto-fix (safe + unsafe)
standardrb --fix-unsafely --no-color
  • --format FORMAT — accepts all RuboCop formatters (emacs, json, quiet, progress, etc.)
  • --no-color — disables ANSI colors
  • --fix — safe automatic fixes (equivalent to RuboCop's -a)
  • --fix-unsafely — all fixes including potentially behavior-changing ones (equivalent to RuboCop's -A)
  • --generate-todo — creates .standard_todo.yml listing files with errors

Standard wraps RuboCop with a fixed, curated ruleset — no per-cop configuration. Configuration is via .standard.yml.

Env var: STANDARDOPTS="--format emacs --no-color" passes options when running via rake standard.

srb tc

# Clean one-line-per-error output
srb tc --color never --no-error-count --no-error-sections

# Quiet (non-critical errors only)
srb tc --quiet --color never
  • --color never — disables ANSI colors (auto detects TTY on stderr)
  • --no-error-count — removes the trailing "Errors: N" summary line
  • --no-error-sections — prints only the first line of each error (removes multi-line context)
  • -q / --quiet — silences all non-critical errors
  • --suppress-error-code CODE — exclude specific error codes (repeatable)
  • --isolate-error-code CODE — include only specific error codes (repeatable)

Sorbet has no JSON format for error output. Default output is file:line: message which is already compact.

reek

# Single-line format, no noise
reek --no-color --no-progress -s lib/

# Structured JSON output
reek --no-color --no-progress -f json lib/
  • -s / --single-line — one line per smell, editor-compatible format
  • --no-color — disables colored output
  • -P / --no-progress — disables per-file progress indicator
  • -f FORMAT — output format: text (default), json, yaml, xml, html, github
  • --no-documentation — hides links to documentation pages
  • --smell SMELL — filter to specific smell detector (repeatable)

Reek has no --quiet flag. Use -s (single-line) for the most compact text output.

brakeman

# Quiet JSON report (most token-efficient)
brakeman -q --no-progress --no-pager --no-color -f json

# Quiet text report
brakeman -q --no-progress --no-pager --no-color

# Summary only
brakeman -q --no-progress --no-pager --no-color --summary
  • -q / --quiet — suppresses informational messages, only outputs the report
  • --no-progress — disables progress indicator
  • --no-pager — outputs directly without paging (pager is on by default)
  • --no-color — disables ANSI colors
  • -f FORMAT — output format: text (default), json, csv, markdown, junit, sarif, github, html, tabs, table, pdf, codeclimate/cc, plain, sonar
  • --summary — only output warning summary
  • -w N — filter by confidence level: 1 (all), 2 (medium+), 3 (high only)
  • --absolute-paths — use absolute file paths in reports

All Brakeman output except the report is sent to stderr.

erb_lint

# Compact one-line-per-offense
bundle exec erb_lint -f compact --lint-all

# Structured JSON output
bundle exec erb_lint -f json --lint-all

# Auto-fix
bundle exec erb_lint -f compact --lint-all -a
  • -f FORMAT / --format — output format: multiline (default), compact, json, junit, gitlab
  • --lint-all — lint all files matching glob (default: **/*.html{+*,}.erb)
  • -a / --autocorrect — auto-fix violations
  • --enable-all-linters — enable every available linter
  • --enable-linters L1,L2 — enable only specific linters

ERB Lint has no --no-color or --quiet flags. The compact format is already clean.

AGENTS.md / CLAUDE.md Template

Copy this into your project's AGENTS.md or CLAUDE.md:

## Running Tools

- Install: `bundle install --quiet`
- Run task: `rake -s taskname`
- Tests (Minitest): `ruby -Ilib:test test/my_test.rb -q`
- Tests (RSpec): `rspec --format progress --no-color --fail-fast`
- Tests (RSpec single): `rspec spec/models/user_spec.rb:42 --no-color --fail-fast`
- Tests (Rails): `bin/rails test --no-color --fail-fast`
- Tests (Rails single): `bin/rails test test/models/user_test.rb:42 --no-color --fail-fast`
- Lint: `rubocop --format emacs --no-color`
- Lint fix: `rubocop -A --no-color`
- Lint (Standard): `standardrb --format emacs --no-color`
- Lint fix (Standard): `standardrb --fix --no-color`
- Type check: `srb tc --color never --no-error-count --no-error-sections`
- Code smells: `reek --no-color --no-progress -s lib/`
- Security scan: `brakeman -q --no-progress --no-pager --no-color`
- ERB lint: `bundle exec erb_lint -f compact --lint-all`
- ERB lint fix: `bundle exec erb_lint -f compact --lint-all -a`
- Generate: `bin/rails generate model User name:string --quiet --force`
- Migrate: `VERBOSE=false bin/rails db:migrate`