rubocop
rubocop documentation
- Version in Mega-Linter: 0.82.0
- Visit Official Web Site
- See How to configure rubocop rules
- If custom
.ruby-lint.ymlconfig file is not found, .ruby-lint.yml will be used
- If custom
- See How to disable rubocop rules in files
- See Index of problems detected by rubocop
Configuration in Mega-Linter
- Enable rubocop by adding
RUBY_RUBOCOPin ENABLE_LINTERS variable - Disable rubocop by adding
RUBY_RUBOCOPin DISABLE_LINTERS variable
- Enable auto-fixes by adding
RUBY_RUBOCOPin APPLY_FIXES variable
| Variable | Description | Default value |
|---|---|---|
| RUBY_RUBOCOP_ARGUMENTS | User custom arguments to add in linter CLI call Ex: -s --foo "bar" |
|
| RUBY_RUBOCOP_FILTER_REGEX_INCLUDE | Custom regex including filter Ex: (src\|lib) |
Include every file |
| RUBY_RUBOCOP_FILTER_REGEX_EXCLUDE | Custom regex excluding filter Ex: (test\|examples) |
Exclude no file |
| RUBY_RUBOCOP_CLI_LINT_MODE | Override default CLI lint mode - file: Calls the linter for each file- list_of_files: Call the linter with the list of files as argument- project: Call the linter from the root of the project |
{linter.cli_lint_mode} |
| RUBY_RUBOCOP_FILE_EXTENSIONS | Allowed file extensions. "*" matches any extension, "" matches empty extension. Empty list excludes all filesEx: [".py", ""] |
[".rb"] |
| RUBY_RUBOCOP_FILE_NAMES_REGEX | File name regex filters. Regular expression list for filtering files by their base names using regex full match. Empty list includes all files Ex: ["Dockerfile(-.+)?", "Jenkinsfile"] |
Include every file |
| RUBY_RUBOCOP_PRE_COMMANDS | List of bash commands to run before the linter | None |
| RUBY_RUBOCOP_POST_COMMANDS | List of bash commands to run after the linter | None |
| RUBY_RUBOCOP_CONFIG_FILE | rubocop configuration file nameUse LINTER_DEFAULT to let the linter find it |
.ruby-lint.yml |
| RUBY_RUBOCOP_RULES_PATH | Path where to find linter configuration file | Workspace folder, then Mega-Linter default rules |
| RUBY_RUBOCOP_DISABLE_ERRORS | Run linter but consider errors as warnings | false |
| RUBY_RUBOCOP_DISABLE_ERRORS_IF_LESS_THAN | Maximum number of errors allowed | 0 |
IDE Integration
Use rubocop in your favorite IDE to catch errors before Mega-Linter !
Mega-Linter Flavours
This linter is available in the following flavours
| Flavor | Description | Embedded linters | Info | |
|---|---|---|---|---|
 |
all | Default Mega-Linter Flavor | 94 |   |
| ruby | Optimized for RUBY based projects | 41 |   |
Behind the scenes
How are identified applicable files
- File extensions:
.rb
How the linting is performed
- rubocop is called one time by identified file
Example calls
rubocop --force-exclusion myfile.rb
rubocop --force-exclusion -c .ruby-lint.yml myfile.rb
rubocop --force-exclusion --safe-auto-correct -c .ruby-lint.yml myfile.rb
Help content
Usage: rubocop [options] [file1, file2, ...]
-L, --list-target-files List all files RuboCop will inspect.
--except [COP1,COP2,...] Disable the given cop(s).
--only [COP1,COP2,...] Run only the given cop(s).
--only-guide-cops Run only cops for rules that link to a
style guide.
-c, --config FILE Specify configuration file.
--force-exclusion Force excluding files specified in the
configuration `Exclude` even if they are
explicitly passed as arguments.
--ignore-parent-exclusion Prevent from inheriting AllCops/Exclude from
parent folders.
--force-default-config Use default configuration even if configuration
files are present in the directory tree.
--auto-gen-config Generate a configuration file acting as a
TODO list.
--exclude-limit COUNT Used together with --auto-gen-config to
set the limit for how many Exclude
properties to generate. Default is 15.
--disable-uncorrectable Used with --auto-correct to annotate any
offenses that do not support autocorrect
with `rubocop:todo` comments.
--no-offense-counts Do not include offense counts in configuration
file generated by --auto-gen-config.
--auto-gen-only-exclude Generate only Exclude parameters and not Max
when running --auto-gen-config, except if the
number of files with offenses is bigger than
exclude-limit.
--no-auto-gen-timestamp Do not include the date and time when
the --auto-gen-config was run in the file it
generates.
--init Generate a .rubocop.yml file in the current directory.
-f, --format FORMATTER Choose an output formatter. This option
can be specified multiple times to enable
multiple formatters at the same time.
[p]rogress is used by default
[a]utogenconf
[c]lang
[e]macs
[fi]les
[fu]ubar
[h]tml
[j]son
[ju]nit
[o]ffenses
[pa]cman
[p]rogress
[q]uiet
[s]imple
[t]ap
[w]orst
custom formatter class name
-o, --out FILE Write output to a file instead of STDOUT.
This option applies to the previously
specified --format, or the default format
if no format is specified.
-r, --require FILE Require Ruby file.
--fail-level SEVERITY Minimum severity (A/R/C/W/E/F) for exit
with error code.
--display-only-fail-level-offenses
Only output offense messages at
the specified --fail-level or above
--show-cops [COP1,COP2,...] Shows the given cops, or all cops by
default, and their configurations for the
current directory.
-F, --fail-fast Inspect files in order of modification
time and stop after the first file
containing offenses.
-C, --cache FLAG Use result caching (FLAG=true) or don't
(FLAG=false), default determined by
configuration parameter AllCops: UseCache.
-d, --debug Display debug info.
-D, --[no-]display-cop-names Display cop names in offense messages.
Default is true.
-E, --extra-details Display extra details in offense messages.
-S, --display-style-guide Display style guide URLs in offense messages.
-a, --auto-correct Auto-correct offenses.
--disable-pending-cops Run without pending cops.
--enable-pending-cops Run with pending cops.
--ignore-disable-comments Run cops even when they are disabled locally
with a comment.
--safe Run only safe cops.
--[no-]color Force color output on or off.
-v, --version Display version.
-V, --verbose-version Display verbose version.
-P, --parallel Use available CPUs to execute inspection in
parallel.
-l, --lint Run only lint cops.
-x, --fix-layout Run only layout cops, with auto-correct on.
--safe-auto-correct Run auto-correct only when it's safe.
-s, --stdin FILE Pipe source from STDIN, using FILE in offense
reports. This is useful for editor integration.
Installation on mega-linter Docker image
- GEM packages (Ruby) :
Example success log
Results of rubocop linter (version 0.82.0)
See documentation on https://megalinter.github.io/descriptors/ruby_rubocop/
-----------------------------------------------
[SUCCESS] .automation/test/ruby/ruby_good_1.rb
Inspecting 1 file
.
1 file inspected, no offenses detected
Example error log
Results of rubocop linter (version 0.82.0)
See documentation on https://megalinter.github.io/descriptors/ruby_rubocop/
-----------------------------------------------
[ERROR] .automation/test/ruby/ruby_bad_1.rb
Inspecting 1 file
C
Offenses:
mp/lint/.automation/test/ruby/ruby_bad_1.rb:1:1: C: Style/FrozenStringLiteralComment: Missing frozen string literal comment.
mp/lint/.automation/test/ruby/ruby_bad_1.rb:11:11: C: Style/StringLiterals: Prefer double-quoted strings unless you need single quotes to avoid extra backslashes for escaping.
File.open('/tmp/urls.txt', " w" ) do | file|
^^^^^^^^^^^^^^^
mp/lint/.automation/test/ruby/ruby_bad_1.rb:11:32: C: Layout/SpaceInsideParens: Space inside parentheses detected.
File.open('/tmp/urls.txt', " w" ) do | file|
^
mp/lint/.automation/test/ruby/ruby_bad_1.rb:11:39: C: Layout/SpaceAroundBlockParameters: Space before first block parameter detected.
File.open('/tmp/urls.txt', " w" ) do | file|
^
mp/lint/.automation/test/ruby/ruby_bad_1.rb:12:24: C: Layout/SpaceAroundBlockParameters: Space after last block parameter detected.
Hook.active.map do |h |
^
mp/lint/.automation/test/ruby/ruby_bad_1.rb:13:13: C: Layout/SpaceInsideArrayLiteralBrackets: Do not use space inside array brackets.
urls = [ ARRAY_OF_URLS_CALLING_INSTANCE]
^
1 file inspected, 6 offenses detected