Add .mill.sc as an alternative file extension to .mill

build.mill

@@ -151,7 +151,7 @@ object Deps {
   val log4j2Core = ivy"org.apache.logging.log4j:log4j-core:2.23.1"
   val osLib = ivy"com.lihaoyi::os-lib:0.10.5"
   val pprint = ivy"com.lihaoyi::pprint:0.9.0"
-  val mainargs = ivy"com.lihaoyi::mainargs:0.7.2"
+  val mainargs = ivy"com.lihaoyi::mainargs:0.7.4"
   val millModuledefsVersion = "0.11.0-M2"
   val millModuledefsString = s"com.lihaoyi::mill-moduledefs:${millModuledefsVersion}"
   val millModuledefs = ivy"${millModuledefsString}"

example/depth/large/11-helper-files/build.mill

@@ -8,8 +8,8 @@ object `package` extends RootModule with MyModule{
     "MY_PROJECT_VERSION" -> versions.myProjectVersion,
   )
 }
-///** See Also: util.sc */
-///** See Also: foo/package */
+///** See Also: util.mill */
+///** See Also: foo/package.mill */
 ///** See Also: foo/versions.mill */
 
 

example/depth/large/13-helper-files-mill-sc/build.mill.sc

@@ -0,0 +1,39 @@
+package build
+import mill._, scalalib._
+import $file.foo.versions
+import $file.util.MyModule
+object `package` extends RootModule with MyModule{
+  def forkEnv = Map(
+    "MY_SCALA_VERSION" -> build.scalaVersion(),
+    "MY_PROJECT_VERSION" -> versions.myProjectVersion,
+  )
+}
+///** See Also: util.mill.sc */
+///** See Also: foo/package.mill.sc */
+///** See Also: foo/versions.mill.sc */
+
+
+// Apart from having `package` files in subfolders to define modules, Mill
+// also allows you to have helper code in any `*.mill` file in the same folder
+// as your `build.mill` or a `package.mill`.
+//
+// Different helper scripts and ``build.mill``/``package`` files can all refer to
+// each other using the `build` object, which marks the root object of your build.
+// In this example:
+//
+// * `build.mill` can be referred to as simple `build`
+// * `util.mill` can be referred to as simple `$file.util`
+// * `foo/package` can be referred to as simple `build.foo`
+// * `foo/versions.mill` can be referred to as simple `$file.foo.versions`
+
+/** Usage
+
+> ./mill run
+Main Env build.util.myScalaVersion: 2.13.14
+Main Env build.foo.versions.myProjectVersion: 0.0.1
+
+> ./mill foo.run
+Foo Env build.util.myScalaVersion: 2.13.14
+Foo Env build.foo.versions.myProjectVersion: 0.0.1
+
+*/

example/depth/large/13-helper-files-mill-sc/foo/package.mill.sc

@@ -0,0 +1,10 @@
+package build.foo
+import mill._, scalalib._
+import $file.util
+import $file.foo.versions.myProjectVersion
+object `package` extends RootModule with build_.util.MyModule {
+  def forkEnv = Map(
+    "MY_SCALA_VERSION" -> util.myScalaVersion,
+    "MY_PROJECT_VERSION" -> myProjectVersion
+  )
+}

example/depth/large/13-helper-files-mill-sc/foo/src/Foo.scala

@@ -0,0 +1,8 @@
+package foo
+
+object Foo {
+  def main(args: Array[String]): Unit = {
+    println("Foo Env build.util.myScalaVersion: " + sys.env("MY_SCALA_VERSION"))
+    println("Foo Env build.foo.versions.myProjectVersion: " + sys.env("MY_PROJECT_VERSION"))
+  }
+}

example/depth/large/13-helper-files-mill-sc/foo/versions.mill.sc

@@ -0,0 +1,3 @@
+package build.foo
+
+def myProjectVersion = "0.0.1"

example/depth/large/13-helper-files-mill-sc/src/Main.scala

@@ -0,0 +1,6 @@
+object Main {
+  def main(args: Array[String]): Unit = {
+    println("Main Env build.util.myScalaVersion: " + sys.env("MY_SCALA_VERSION"))
+    println("Main Env build.foo.versions.myProjectVersion: " + sys.env("MY_PROJECT_VERSION"))
+  }
+}

example/depth/large/13-helper-files-mill-sc/util.mill.sc

@@ -0,0 +1,9 @@
+package build
+
+import mill._, scalalib._
+
+def myScalaVersion = "2.13.14"
+
+trait MyModule extends ScalaModule {
+  def scalaVersion = myScalaVersion
+}

main/client/src/mill/main/client/CodeGenConstants.java

@@ -21,17 +21,17 @@ public class CodeGenConstants {
     /**
      * The name of the root build file
      */
-    final public static String[] rootBuildFileNames = {"build.mill", "build.sc"};
+    final public static String[] rootBuildFileNames = {"build.mill", "build.mill.sc", "build.sc"};
 
     /**
      * The name of any sub-folder build files
      */
-    final public static String[] nestedBuildFileNames = {"package.mill", "package.sc"};
+    final public static String[] nestedBuildFileNames = {"package.mill", "package.mill.sc", "package.sc"};
 
     /**
      * The extensions used by build files
      */
-    final public static String[] buildFileExtensions = {"mill", "sc"};
+    final public static String[] buildFileExtensions = {"mill", "mill.sc", "sc"};
 
     /**
      * The user-facing name for the root of the module tree.

mill-build/src/ExampleParser.scala

@@ -6,7 +6,7 @@ object ExampleParser {
     val states = collection.mutable.Buffer("scala")
     val chunks = collection.mutable.Buffer(collection.mutable.Buffer.empty[String])
 
-    val rootBuildFileNames = Seq("build.sc", "build.mill")
+    val rootBuildFileNames = Seq("build.sc", "build.mill", "build.mill.sc")
     val buildFile = rootBuildFileNames.map(testRepoRoot / _).find(os.exists)
     for (line <- os.read.lines(buildFile.get)) {
       val (newState, restOpt) = line match {

runner/linenumbers/src/mill/linenumbers/LineNumberPlugin.scala

@@ -30,7 +30,7 @@ class LineNumberPlugin(val global: Global) extends Plugin {
 
 object LineNumberPlugin {
   def apply(g: Global)(unit: g.CompilationUnit): Unit = {
-    if (buildFileExtensions.exists(g.currentSource.file.hasExtension(_))) {
+    if (buildFileExtensions.exists(ex => g.currentSource.file.name.endsWith(s".$ex"))) {
 
       val str = new String(g.currentSource.content)
       val lines = str.linesWithSeparators.toVector

runner/src/mill/runner/CodeGen.scala

@@ -18,18 +18,17 @@ object CodeGen {
       millTopLevelProjectRoot: os.Path
   ): Unit = {
     for (scriptSource <- scriptSources) {
-      // pprint.log(scriptSource)
       val scriptPath = scriptSource.path
       val specialNames = (nestedBuildFileNames ++ rootBuildFileNames).toSet
 
       val isBuildScript = specialNames(scriptPath.last)
       val scriptFolderPath = scriptPath / os.up
 
-      if (scriptFolderPath == projectRoot && scriptPath.baseName == "package") {
+      if (scriptFolderPath == projectRoot && scriptPath.last.split('.').head == "package") {
         throw Result.Failure(s"Mill ${scriptPath.last} files can only be in subfolders")
       }
 
-      if (scriptFolderPath != projectRoot && scriptPath.baseName == "build") {
+      if (scriptFolderPath != projectRoot && scriptPath.last.split('.').head == "build") {
         throw Result.Failure(s"Mill ${scriptPath.last} files can only be in the project root")
       }
 
@@ -86,7 +85,7 @@ object CodeGen {
         if (!isBuildScript) {
           s"""$pkgLine
              |$aliasImports
-             |object ${backtickWrap(scriptPath.baseName)} {
+             |object ${backtickWrap(scriptPath.last.split('.').head)} {
              |$markerComment
              |$scriptCode
              |}""".stripMargin

runner/src/mill/runner/FileImportGraph.scala

@@ -51,7 +51,6 @@ object FileImportGraph {
     var millImport = false
 
     def processScript(s: os.Path, useDummy: Boolean = false): Unit = {
-
       val readFileEither = scala.util.Try {
         val content = if (useDummy) "" else os.read(s)
         val fileName = s.relativeTo(topLevelProjectRoot).toString
@@ -67,7 +66,7 @@ object FileImportGraph {
             val expectedImportSegments = expectedImportSegments0.map(backtickWrap).mkString(".")
             if (
               // Legacy `.sc` files have their package build be optional
-              s.ext == "mill" &&
+              (s.last.endsWith(".mill") || s.last.endsWith(".mill.sc")) &&
               expectedImportSegments != importSegments &&
               // Root build.mill file has its `package build` be optional
               !(importSegments == "" && rootBuildFileNames.contains(s.last))
@@ -137,7 +136,7 @@ object FileImportGraph {
           case ImportTree(Seq(("$file", end0), rest @ _*), mapping, start, end) =>
             // Only recursively explore imports from legacy `.sc` files, as new `.mill` files
             // do file discovery via scanning folders containing `package.mill` files
-            if (s.ext == "sc") {
+            if (s.last.endsWith(".sc") && !s.last.endsWith(".mill.sc")) {
               val nextPaths = mapping.map { case (lhs, rhs) =>
                 nextPathFor(s, rest.map(_._1) :+ lhs)
               }
@@ -167,8 +166,10 @@ object FileImportGraph {
     val useDummy = rootBuildFiles.isEmpty
     val foundRootBuildFileName: String = rootBuildFiles.getOrElse(rootBuildFileNames.head)
 
-    val buildFileExtension = buildFileExtensions.find(foundRootBuildFileName.endsWith).get
-    val nestedBuildFileName = nestedBuildFileNames.find(_.endsWith(buildFileExtension)).get
+    val buildFileExtension =
+      buildFileExtensions.find(ex => foundRootBuildFileName.endsWith(s".$ex")).get
+
+    val nestedBuildFileName = s"package.$buildFileExtension"
 
     processScript(projectRoot / foundRootBuildFileName, useDummy)
     val buildFiles = os
@@ -184,7 +185,7 @@ object FileImportGraph {
 
     val adjacentScripts = (projectRoot +: buildFiles.map(_ / os.up))
       .flatMap(os.list(_))
-      .filter(_.ext == buildFileExtension)
+      .filter(_.last.endsWith(s".$buildFileExtension"))
 
     (buildFiles ++ adjacentScripts).foreach(processScript(_))
 

scalalib/src/mill/scalalib/Lib.scala

@@ -132,7 +132,9 @@ object Lib {
       root <- sources
       if os.exists(root.path)
       path <- (if (os.isDir(root.path)) os.walk(root.path) else Seq(root.path))
-      if os.isFile(path) && (extensions.exists(path.ext == _) && !isHiddenFile(path))
+      if os.isFile(path) && (extensions.exists(ex => path.last.endsWith(s".$ex")) && !isHiddenFile(
+        path
+      ))
     } yield path
   }
 

scalalib/src/mill/scalalib/scalafmt/ScalafmtModule.scala

@@ -57,7 +57,9 @@ trait ScalafmtModule extends JavaModule {
       file <- {
         if (os.isDir(pathRef.path)) {
           os.walk(pathRef.path).filter(file =>
-            os.isFile(file) && (file.ext == "scala" || buildFileExtensions.contains(file.ext))
+            os.isFile(file) && (file.ext == "scala" || buildFileExtensions.exists(ex =>
+              file.last.endsWith(s".$ex")
+            ))
           )
         } else {
           Seq(pathRef.path)