.

build.mill

@@ -758,8 +758,6 @@ object dist0 extends MillPublishJavaModule {
     build.contrib.jmh.testDep(),
     build.contrib.playlib.testDep(),
     build.contrib.playlib.worker("2.8").testDep(),
-    build.contrib.errorprone.testDep(),
-    build.contrib.checkstyle.testDep(),
     build.bsp.worker.testDep(),
     build.testkit.testDep()
   )

contrib/package.mill

@@ -211,18 +211,4 @@ object `package` extends RootModule {
     def compileModuleDeps = Seq(build.scalalib)
     def testModuleDeps = super.testModuleDeps ++ Seq(build.scalalib)
   }
-
-  object errorprone extends ContribModule with BuildInfo {
-    def compileModuleDeps = Seq(build.scalalib)
-    def testModuleDeps = super.testModuleDeps ++ Seq(build.scalalib)
-    def buildInfoPackageName = "mill.contrib.errorprone"
-    def buildInfoObjectName = "BuildInfo"
-    def buildInfoMembers =
-      Seq(BuildInfo.Value("errorProneVersion", Deps.RuntimeDeps.errorProneCore.version))
-  }
-
-  object checkstyle extends ContribModule {
-    def compileModuleDeps = Seq(build.scalalib)
-    def testModuleDeps = super.testModuleDeps ++ Seq(build.scalalib)
-  }
 }

example/javalib/linting/1-error-prone/build.mill

@@ -3,10 +3,8 @@
 
 
 package build
-import mill._, javalib._
-import mill.contrib.errorprone._
+import mill._, javalib._, errorprone._
 
-import $ivy.`com.lihaoyi::mill-contrib-errorprone:`
 
 object `package` extends RootModule with JavaModule with ErrorProneModule {
   def errorProneOptions = Seq("-XepAllErrorsAsWarnings")
@@ -29,4 +27,34 @@ object `package` extends RootModule with JavaModule with ErrorProneModule {
 [warn]               ^
 */
 
-// Find more details on the xref:contrib/errorprone.adoc[ErrorProne plugin page].
+// :page-aliases: Plugin_ErrorProne.adoc
+//
+// https://errorprone.info/index[Error Prone] augments the Java compiler's type checker and detect common mistakes at compile time.
+//
+// You just need to mix the `ErrorProneModule` into your `JavaModule` and it will automatically run with every compilation.
+//
+// .`build.mill.scala`: Enable `ErrorProne` in a module
+// [source,scala]
+// ----
+// package build
+// import mill._, scalalib._
+//
+// import $ivy.`com.lihaoyi::mill-contrib-errorprone:`
+// import mill.contrib.errorprone.ErrorProneModule
+//
+// object foo extends JavaModule with ErrorProneModule {
+// }
+// ----
+//
+// == Configuration
+//
+// The following configuration options exist:
+//
+// `def errorProneVersion: T[String]`::
+// The `error-prone` version to use. Defaults to [[BuildInfo.errorProneVersion]], the version used to build and test the module.
+// Find the latest at https://mvnrepository.com/artifact/com.google.errorprone/error_prone_core[mvnrepository.com]
+//
+// `def errorProneOptions: T[Seq[String]]`::
+//  Options directly given to the `error-prone` processor.
+// Those are documented as "flags" at https://errorprone.info/docs/flags
+//

example/javalib/linting/2-checkstyle/build.mill

@@ -1,8 +1,5 @@
 package build
-import mill._, javalib._
-import $ivy.`com.lihaoyi::mill-contrib-checkstyle:`
-
-import mill.contrib.checkstyle._
+import mill._, javalib._, checkstyle._
 
 object `package` extends RootModule with CheckstyleModule {
   def checkstyleVersion = "9.3"
@@ -34,4 +31,129 @@ Audit done.
 
 > ./mill checkstyle # after fixing the violations, checkstyle no longer errors
 Audit done.
-*/
+*/
+
+// Performs quality checks on Java source files using https://checkstyle.org[Checkstyle] and generates reports from these checks.
+//
+// To use this plugin in a Java/Scala module,
+//
+// 1. Extend `mill.contrib.checkstyle.CheckstyleModule`.
+// 2. Define a https://checkstyle.org/config.html[configuration] file `checkstyle-config.xml`.
+// 3. Run the `checkstyle` command.
+//
+// === checkstyle
+//
+// - flags
+// [source,sh]
+// ----
+//
+// // if an exception should be raised when violations are found
+// checkstyle --check
+//
+// // if Checkstyle output report should be written to System.out
+// checkstyle --stdout
+// ----
+//
+// - sources (optional)
+// [source,sh]
+// ----
+// // incorrect paths will cause a command failure
+// // checkstyle a/b
+//
+// // you can specify paths relative to millSourcePath
+// checkstyle src/a/b
+//
+// // process a single file
+// checkstyle src/a/B.java
+//
+// // process multiple sources
+// checkstyle src/a/b src/c/d src/e/F.java
+//
+// // process with flags
+// checkstyle --check --stdout src/a/b src/c/d
+//
+// // process all module sources
+// checkstyle
+// ----
+//
+// === Shared configuration
+//
+// To share `checkstyle-config.xml` across modules, adapt the following example.
+// [source,scala]
+// ----
+// import mill._
+// import mill.contrib.checkstyle.CheckstyleModule
+// import mill.scalalib._
+//
+// object foo extends Module {
+//
+//   object bar extends MyModule
+//   object baz extends Module {
+//     object fizz extends MyModule
+//     object buzz extends MyModule
+//   }
+//
+//   trait MyModule extends JavaModule with CheckstyleModule {
+//
+//     override def checkstyleConfig = Task {
+//       api.PathRef(T.workspace / "checkstyle-config.xml")
+//     }
+//   }
+// }
+// ----
+//
+//
+// === Limitations
+//
+// - Version `6.3` or above is required for `plain` and `xml` formats.
+// - Setting `checkstyleOptions` might cause failures with legacy versions.
+//
+// == CheckstyleXsltModule
+//
+// This plugin extends the `mill.contrib.checkstyle.CheckstyleModule` with the ability to generate reports by applying https://www.w3.org/TR/xslt/[XSL Transformations] on a Checkstyle output report.
+//
+// === Auto detect XSL Transformations
+//
+// XSLT files are detected automatically provided a prescribed directory structure is followed.
+// [source,scala]
+// ----
+// /**
+//  * checkstyle-xslt
+//  *  ├─ html
+//  *  │   ├─ xslt0.xml
+//  *  │   └─ xslt1.xml
+//  *  └─ pdf
+//  *      ├─ xslt1.xml
+//  *      └─ xslt2.xml
+//  *
+//  * html/xslt0.xml -> xslt0.html
+//  * html/xslt1.xml -> xslt1.html
+//  * pdf/xslt1.xml  -> xslt1.pdf
+//  * pdf/xslt2.xml  -> xslt2.pdf
+//  */
+// ----
+//
+// === Specify XSL Transformations manually
+//
+// For a custom setup, adapt the following example.
+// [source,scala]
+// ----
+// import mill._
+// import mill.api.PathRef
+// import mill.contrib.checkstyle.CheckstyleXsltModule
+// import mill.contrib.checkstyle.CheckstyleXsltReport
+// import mill.scalalib._
+//
+// object foo extends JavaModule with CheckstyleXsltModule {
+//
+//     override def checkstyleXsltReports = Task {
+//       Set(
+//         CheckstyleXsltReport(
+//           PathRef(millSourcePath / "checkstyle-no-frames.xml"),
+//           PathRef(T.dest / "checkstyle-no-frames.html"),
+//         )
+//       )
+//   }
+// }
+// ----
+//

scalalib/package.mill

@@ -70,7 +70,8 @@ object `package` extends RootModule with build.MillStableScalaModule {
           s"${d.dep.module.organization.value}:${d.dep.module.name.value}:${d.version}"
         },
         "Dependency to jupiter-interface"
-      )
+      ),
+      BuildInfo.Value("errorProneVersion", build.Deps.RuntimeDeps.errorProneCore.version)
     )
   }
 

contrib/checkstyle/src/mill/contrib/checkstyle/CheckstyleArgs.scala → scalalib/src/mill/javalib/checkstyle/CheckstyleArgs.scala

@@ -1,4 +1,4 @@
-package mill.contrib.checkstyle
+package mill.javalib.checkstyle
 
 import mainargs.{Leftover, ParserForClass, main}