ktlint
ktlint documentation
- Version in MegaLinter: 1.0.1
- Visit Official Web Site
- See Index of problems detected by ktlint
Configuration in MegaLinter
- Enable ktlint by adding
KOTLIN_KTLINT
in ENABLE_LINTERS variable - Disable ktlint by adding
KOTLIN_KTLINT
in DISABLE_LINTERS variable
- Enable autofixes by adding
KOTLIN_KTLINT
in APPLY_FIXES variable
Variable | Description | Default value |
---|---|---|
KOTLIN_KTLINT_ARGUMENTS | User custom arguments to add in linter CLI call Ex: -s --foo "bar" |
|
KOTLIN_KTLINT_COMMAND_REMOVE_ARGUMENTS | User custom arguments to remove from command line before calling the linter Ex: -s --foo "bar" |
|
KOTLIN_KTLINT_FILTER_REGEX_INCLUDE | Custom regex including filter Ex: (src\|lib) |
Include every file |
KOTLIN_KTLINT_FILTER_REGEX_EXCLUDE | Custom regex excluding filter Ex: (test\|examples) |
Exclude no file |
KOTLIN_KTLINT_CLI_LINT_MODE | Override default CLI lint mode - file : Calls the linter for each file- project : Call the linter from the root of the project |
file |
KOTLIN_KTLINT_FILE_EXTENSIONS | Allowed file extensions. "*" matches any extension, "" matches empty extension. Empty list excludes all filesEx: [".py", ""] |
[".kt", ".kts"] |
KOTLIN_KTLINT_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 |
KOTLIN_KTLINT_PRE_COMMANDS | List of bash commands to run before the linter | None |
KOTLIN_KTLINT_POST_COMMANDS | List of bash commands to run after the linter | None |
KOTLIN_KTLINT_UNSECURED_ENV_VARIABLES | List of env variables explicitly not filtered before calling KOTLIN_KTLINT and its pre/post commands | None |
KOTLIN_KTLINT_DISABLE_ERRORS | Run linter but consider errors as warnings | false |
KOTLIN_KTLINT_DISABLE_ERRORS_IF_LESS_THAN | Maximum number of errors allowed | 0 |
KOTLIN_KTLINT_CLI_EXECUTABLE | Override CLI executable | ['ktlint'] |
IDE Integration
Use ktlint in your favorite IDE to catch errors before MegaLinter !
IDE | Extension Name | Install | |
---|---|---|---|
Emacs | flycheck-kotlin | Visit Web Site | |
vim | ale | Visit Web Site |
MegaLinter Flavours
This linter is available in the following flavours
Flavor | Description | Embedded linters | Info | |
---|---|---|---|---|
![]() |
all | Default MegaLinter Flavor | 118 | |
c_cpp | Optimized for pure C/C++ projects | 53 | ||
cupcake | MegaLinter for the most commonly used languages | 85 | ||
documentation | MegaLinter for documentation projects | 51 | ||
dotnet | Optimized for C, C++, C# or VB based projects | 63 | ||
dotnetweb | Optimized for C, C++, C# or VB based projects with JS/TS | 72 | ||
go | Optimized for GO based projects | 53 | ||
java | Optimized for JAVA based projects | 55 | ||
javascript | Optimized for JAVASCRIPT or TYPESCRIPT based projects | 60 | ||
php | Optimized for PHP based projects | 54 | ||
python | Optimized for PYTHON based projects | 62 | ||
ruby | Optimized for RUBY based projects | 51 | ||
rust | Optimized for RUST based projects | 51 | ||
salesforce | Optimized for Salesforce based projects | 55 | ||
swift | Optimized for SWIFT based projects | 51 | ||
terraform | Optimized for TERRAFORM based projects | 55 |
Behind the scenes
How are identified applicable files
- File extensions:
.kt
,.kts
How the linting is performed
- ktlint is called one time by identified file (
file
CLI lint mode)
Example calls
ktlint myfile.kt
ktlint --format myfile.kt
Help content
An anti-bikeshedding Kotlin linter with built-in formatter.
(https://github.com/pinterest/ktlint).
Usage:
ktlint <flags> [patterns]
java -jar ktlint.jar <flags> [patterns]
Examples:
# Check the style of all Kotlin files (ending with '.kt' or '.kts') inside
the current dir (recursively).
#
# Hidden folders will be skipped.
ktlint
# Check only certain locations starting from the current directory.
#
# Prepend ! to negate the pattern, KtLint uses .gitignore pattern style
syntax.
# Globs are applied starting from the last one.
#
# Hidden folders will be skipped.
# Check all '.kt' files in 'src/' directory, but ignore files ending with
'Test.kt':
ktlint "src/**/*.kt" "!src/**/*Test.kt"
# Check all '.kt' files in 'src/' directory, but ignore 'generated' directory
and its subdirectories:
ktlint "src/**/*.kt" "!src/**/generated/**"
# Auto-correct style violations.
ktlint -F "src/**/*.kt"
# Using custom reporter jar and overriding report location
ktlint --reporter=csv,artifact=/path/to/reporter/csv.jar,
output=my-custom-report.csv
Flags:
--code-style=<codeStyle>
Defines the code style (ktlint_official, intellij_idea
or android_studio) to be used for formatting the
code. This option is deprecated, and will be removed
in Ktlint 1.1. The code style has to be defined as '.
editorconfig' property 'ktlint_code_style'.
--color Make output colorful
--color-name=<colorName>
Customize the output color
--disabled_rules=<disabledRules>
Comma-separated list of rules to globally disable. This
option is deprecated, and will be removed in Ktlint
1.1. The disabled rules have to be defined as '.
editorconfig' properties. See https://pinterest.
github.io/ktlint/1.0.0
/faq/#how-do-i-enable-or-disable-a-rule
-F, --format Fix deviations from the code style when possible
--limit=<limit> Maximum number of errors to show (default: show all)
--relative Print files relative to the working directory (e.g.
dir/file.kt instead of /home/user/project/dir/file.kt)
--reporter=<reporterConfigurations>
A reporter to use (built-in: plain (default), plain?
group_by_file, plain-summary, json, sarif,
checkstyle, html). To use a third-party reporter
specify a path to a JAR file on the filesystem via ',
artifact=' option. To override reporter output, use ',
output=' option.
-R, --ruleset=<rulesetJarPaths>
A path to a JAR file containing additional ruleset(s)
--stdin Read file from stdin
--patterns-from-stdin[=<stdinDelimiter>]
Read additional patterns to check/format from stdin.
Patterns are delimited by the given argument.
(default is newline) If the argument is an empty
string, the NUL byte is used.
--editorconfig=<editorConfigPath>
Path to the default '.editorconfig'. A property value
from this file is used only when no '.editorconfig'
file on the path to the source file specifies that
property. Note: up until ktlint 0.46 the property
value in this file used to override values found in '.
editorconfig' files on the path to the source file.
--experimental Enable experimental rules. This option is deprecated,
and will be removed in Ktlint 1.1. The experimental
flag has to be set as '.editorconfig' property
'ktlint_experimental'. See https://pinterest.github.
io/ktlint/1.0.0
/faq/#how-do-i-enable-or-disable-a-rule-set
--baseline=<baselinePath>
Defines a baseline file to check against
-l, --log-level=<minLogLevel>
Defines the minimum log level (trace, debug, info,
warn, error) or none to suppress all logging
-h, --help Show this help message and exit.
-V, --version Print version information and exit.
Commands:
installGitPreCommitHook Install git hook to automatically check files for
style violations on commit
installGitPrePushHook Install git hook to automatically check files for
style violations before push
generateEditorConfig Generate kotlin style section for '.editorconfig'
file.
Installation on mega-linter Docker image
- Dockerfile commands :
RUN curl --retry 5 --retry-delay 5 -sSLO https://github.com/pinterest/ktlint/releases/latest/download/ktlint && \
chmod a+x ktlint && \
mv "ktlint" /usr/bin/