/spotless

Keep your code spotless

Primary LanguageJavaApache License 2.0Apache-2.0

Spotless: Keep your code spotless

Gradle Plugin Maven Plugin SBT Plugin

Spotless can format <antlr | c | c# | c++ | css | flow | graphql | groovy | html | java | javascript | json | jsx | kotlin | less | license headers | markdown | objective-c | protobuf | python | scala | scss | shell | sql | typeScript | vue | yaml | anything> using <gradle | maven | sbt | anything>.

You probably want one of the links below:

❇️ Spotless for Gradle (with integrations for VS Code and IntelliJ)

user@machine repo % ./gradlew build
:spotlessJavaCheck FAILED
  The following files had format violations:
  src\main\java\com\diffplug\gradle\spotless\FormatExtension.java
    -\t\t····if·(targets.length·==·0)·{
    +\t\tif·(targets.length·==·0)·{
  Run './gradlew spotlessApply' to fix these violations.
user@machine repo % ./gradlew spotlessApply
:spotlessApply
BUILD SUCCESSFUL
user@machine repo % ./gradlew build
BUILD SUCCESSFUL

❇️ Spotless for Maven

user@machine repo % mvn spotless:check
[ERROR]  > The following files had format violations:
[ERROR]  src\main\java\com\diffplug\gradle\spotless\FormatExtension.java
[ERROR]    -\t\t····if·(targets.length·==·0)·{
[ERROR]    +\t\tif·(targets.length·==·0)·{
[ERROR]  Run 'mvn spotless:apply' to fix these violations.
user@machine repo % mvn spotless:apply
[INFO] BUILD SUCCESS
user@machine repo % mvn spotless:check
[INFO] BUILD SUCCESS

❇️ Spotless for SBT (external for now)

Other build systems

How it works (for potential contributors)

Ideally, a code formatter can do more than just find formatting errors - it should fix them as well. Such a formatter is just a Function<String, String>, which returns a formatted version of its potentially unformatted input.

It's easy to build such a function, but there are some gotchas and lots of integration work (newlines, character encodings, idempotency, git ratcheting, and build-system integration). Spotless tackles those for you so you can focus on just a simple Function<String, String> which can compose with any of the other formatters and build tools in Spotless' arsenal.

Current feature matrix

Feature / FormatterStep gradle maven sbt (Your build tool here)
Automatic idempotency safeguard 👍 👍 👍 ⬜
Misconfigured encoding safeguard 👍 👍 👍 ⬜
Toggle with spotless:off and spotless:on 👍 👍 ⬜ ⬜
Ratchet from origin/main or other git ref 👍 👍 ⬜ ⬜
Define line endings using git 👍 👍 👍 ⬜
Fast incremental format and up-to-date check 👍 👍 ⬜ ⬜
Fast format on fresh checkout using buildcache 👍 ⬜ ⬜ ⬜
generic.EndWithNewlineStep 👍 👍 ⬜ ⬜
generic.IndentStep 👍 👍 ⬜ ⬜
generic.Jsr223Step ⬜ 👍 ⬜ ⬜
generic.LicenseHeaderStep 👍 👍 👍 ⬜
generic.NativeCmdStep 👍 👍 ⬜ ⬜
generic.ReplaceRegexStep 👍 👍 ⬜ ⬜
generic.ReplaceStep 👍 👍 ⬜ ⬜
generic.TrimTrailingWhitespaceStep 👍 👍 ⬜ ⬜
antlr4.Antlr4FormatterStep 👍 👍 ⬜ ⬜
biome.BiomeStep 👍 👍 ⬜ ⬜
cpp.ClangFormatStep 👍 ⬜ ⬜ ⬜
cpp.EclipseFormatterStep 👍 👍 👍 ⬜
go.GofmtFormatStep 👍 ⬜ ⬜ ⬜
gherkin.GherkinUtilsStep 👍 👍 ⬜ ⬜
groovy.GrEclipseFormatterStep 👍 👍 👍 ⬜
java.GoogleJavaFormatStep 👍 👍 👍 ⬜
java.ImportOrderStep 👍 👍 👍 ⬜
java.PalantirJavaFormatStep 👍 👍 ⬜ ⬜
java.RemoveUnusedImportsStep 👍 👍 👍 ⬜
java.EclipseJdtFormatterStep 👍 👍 👍 ⬜
java.FormatAnnotationsStep 👍 👍 ⬜ ⬜
java.CleanthatJavaStep 👍 👍 ⬜ ⬜
json.gson.GsonStep 👍 👍 ⬜ ⬜
json.JacksonJsonStep 👍 👍 ⬜ ⬜
json.JsonSimpleStep 👍 👍 ⬜ ⬜
json.JsonPatchStep 👍 👍 ⬜ ⬜
kotlin.KtLintStep 👍 👍 👍 ⬜
kotlin.KtfmtStep 👍 👍 ⬜ ⬜
kotlin.DiktatStep 👍 👍 ⬜ ⬜
markdown.FreshMarkStep 👍 ⬜ ⬜ ⬜
markdown.FlexmarkStep 👍 👍 ⬜ ⬜
npm.EslintFormatterStep 👍 👍 ⬜ ⬜
npm.PrettierFormatterStep 👍 👍 ⬜ ⬜
npm.TsFmtFormatterStep 👍 👍 ⬜ ⬜
pom.SortPomStep 👍 👍 ⬜ ⬜
protobuf.BufStep 👍 ⬜ ⬜ ⬜
python.BlackStep 👍 ⬜ ⬜ ⬜
scala.ScalaFmtStep 👍 👍 👍 ⬜
shell.ShfmtStep 👍 👍 ⬜ ⬜
sql.DBeaverSQLFormatterStep 👍 👍 👍 ⬜
wtp.EclipseWtpFormatterStep 👍 👍 ⬜ ⬜
yaml.JacksonYamlStep 👍 👍 ⬜ ⬜
(Your FormatterStep here) ⬜ ⬜ ⬜ ⬜

Why are there empty squares?

Many projects get harder to work on as they get bigger. Spotless is easier to work on than ever, and one of the reasons why is that we don't require contributors to "fill the matrix". If you want to add Bazel support, we'd happily accept the PR even if it only supports the one formatter you use. And if you want to add FooFormatter support, we'll happily accept the PR even if it only supports the one build system you use.

Once someone has filled in one square of the formatter/build system matrix, it's easy for interested parties to fill in any empty squares, since you'll now have a working example for every piece needed.

Acknowledgements