Reviewed and updated some target types (#2494)

Reviewed return types of major modules.

1. Replaced `Input` and `Sources` with their respective target types,
e.g. `T[Seq[PathRef]]`.
2. Added missing return types for public targets
3. Changed some extension points in `GenIdeaModule` from `Command` to
`Task` and updated `IdeaConfigFile`. This is a binary breaking change,
but better matches their purpose

Pull request: #2494

contrib/scalapblib/src/mill/contrib/scalapblib/ScalaPBModule.scala

@@ -52,7 +52,7 @@ trait ScalaPBModule extends ScalaModule {
 
   def scalaPBProtocPath: T[Option[String]] = T { None }
 
-  def scalaPBSources: Sources = T.sources {
+  def scalaPBSources: T[Seq[PathRef]] = T.sources {
     millSourcePath / "protobuf"
   }
 

contrib/scalapblib/test/src/mill/contrib/scalapblib/TutorialTests.scala

@@ -46,7 +46,7 @@ object TutorialTests extends TestSuite {
 
   object TutorialWithSpecificSources extends TutorialBase {
     object core extends TutorialModule {
-      override def scalaPBSources: Sources = T.sources {
+      override def scalaPBSources: T[Seq[PathRef]] = T.sources {
         millSourcePath / "protobuf" / "tutorial" / "Tutorial.proto"
       }
 

contrib/scoverage/src/mill/contrib/scoverage/ScoverageModule.scala

@@ -186,7 +186,7 @@ trait ScoverageModule extends ScalaModule { outer: ScalaModule =>
      * The persistent data dir used to store scoverage coverage data.
      * Use to store coverage data at compile-time and by the various report targets.
      */
-    def data: Persistent[PathRef] = T.persistent {
+    def data: T[PathRef] = T.persistent {
       // via the persistent target, we ensure, the dest dir doesn't get cleared
       PathRef(T.dest)
     }
@@ -195,14 +195,14 @@ trait ScoverageModule extends ScalaModule { outer: ScalaModule =>
     override def allSources: Target[Seq[PathRef]] = T { outer.allSources() }
     override def moduleDeps: Seq[JavaModule] = outer.moduleDeps
     override def compileModuleDeps: Seq[JavaModule] = outer.compileModuleDeps
-    override def sources: Sources = T.sources { outer.sources() }
-    override def resources: Sources = T.sources { outer.resources() }
+    override def sources: T[Seq[PathRef]] = T.sources { outer.sources() }
+    override def resources: T[Seq[PathRef]] = T.sources { outer.resources() }
     override def scalaVersion = T { outer.scalaVersion() }
     override def repositoriesTask: Task[Seq[Repository]] = T.task { outer.repositoriesTask() }
-    override def compileIvyDeps: Target[Loose.Agg[Dep]] = T { outer.compileIvyDeps() }
-    override def ivyDeps: Target[Loose.Agg[Dep]] =
+    override def compileIvyDeps: Target[Agg[Dep]] = T { outer.compileIvyDeps() }
+    override def ivyDeps: Target[Agg[Dep]] =
       T { outer.ivyDeps() ++ outer.scoverageRuntimeDeps() }
-    override def unmanagedClasspath: Target[Loose.Agg[PathRef]] = T { outer.unmanagedClasspath() }
+    override def unmanagedClasspath: Target[Agg[PathRef]] = T { outer.unmanagedClasspath() }
 
     /** Add the scoverage scalac plugin. */
     override def scalacPluginIvyDeps: Target[Loose.Agg[Dep]] =

contrib/twirllib/src/mill/twirllib/TwirlModule.scala

@@ -19,7 +19,7 @@ trait TwirlModule extends mill.Module { twirlModule =>
    */
   def twirlScalaVersion: T[String]
 
-  def twirlSources: Sources = T.sources {
+  def twirlSources: T[Seq[PathRef]] = T.sources {
     millSourcePath / "views"
   }
 

contrib/versionfile/src/mill/contrib/versionfile/VersionFileModule.scala

@@ -5,33 +5,33 @@ import mill._, scalalib._
 trait VersionFileModule extends Module {
 
   /** The file containing the current version. */
-  def versionFile: Source = T.source(millSourcePath / "version")
+  def versionFile: T[PathRef] = T.source(millSourcePath / "version")
 
   /** The current version. */
   def currentVersion: T[Version] = T { Version.of(os.read(versionFile().path).trim) }
 
   /** The release version. */
-  def releaseVersion = T { currentVersion().asRelease }
+  def releaseVersion: T[Version] = T { currentVersion().asRelease }
 
   /** The next snapshot version. */
-  def nextVersion(bump: String) = T.command { currentVersion().asSnapshot.bump(bump) }
+  def nextVersion(bump: String): Task[Version] = T.task { currentVersion().asSnapshot.bump(bump) }
 
   /** Writes the release version to file. */
-  def setReleaseVersion = T {
+  def setReleaseVersion(): Command[Unit] = T.command {
     setVersionTask(releaseVersion)()
   }
 
   /** Writes the next snapshot version to file. */
-  def setNextVersion(bump: String) = T.command {
+  def setNextVersion(bump: String): Command[Unit] = T.command {
     setVersionTask(nextVersion(bump))()
   }
 
   /** Writes the given version to file. */
-  def setVersion(version: Version) = T.command {
-    setVersionTask(T.task { version })()
+  def setVersion(version: Task[Version]): Command[Unit] = T.command {
+    setVersionTask(version)()
   }
 
-  protected def setVersionTask(version: T[Version]) = T.task {
+  protected def setVersionTask(version: Task[Version]) = T.task {
     T.log.info(generateCommitMessage(version()))
     writeVersionToFile(versionFile(), version())
   }

contrib/versionfile/test/src/mill/contrib/versionfile/VersionFileModuleTests.scala

@@ -1,5 +1,6 @@
 package mill.contrib.versionfile
 
+import mill.T
 import mill.api.Result
 import mill.util.{TestEvaluator, TestUtil}
 import utest.{TestSuite, Tests, assert, assertMatch, intercept, test}
@@ -114,7 +115,7 @@ object VersionFileModuleTests extends TestSuite {
 
       test("setReleaseVersion") - workspaceTest(versions: _*) { eval =>
         val expected = eval(TestModule.versionFile.releaseVersion)
-        val write = eval(TestModule.versionFile.setReleaseVersion)
+        val write = eval(TestModule.versionFile.setReleaseVersion())
         val actual = eval(TestModule.versionFile.currentVersion)
         assert(expected.value == actual.value)
       }
@@ -129,7 +130,7 @@ object VersionFileModuleTests extends TestSuite {
 
       test("setVersion") - workspaceTest(versions: _*) { eval =>
         val expected = Version.Release(1, 2, 4)
-        val write = eval(TestModule.versionFile.setVersion(expected))
+        val write = eval(TestModule.versionFile.setVersion(T.task(expected)))
         val actual = eval(TestModule.versionFile.currentVersion)
         assert(actual.value == Right(expected))
       }

integration/feature/gen-idea/repo/extended/build.sc

@@ -1,8 +1,8 @@
 import $ivy.`org.scalameta::munit:0.7.29`
 
+import mill._
 import mill.api.PathRef
 import mill.scalalib
-import mill.define.Command
 import mill.scalalib.GenIdeaModule._
 import mill.scalalib.TestModule
 
@@ -18,8 +18,8 @@ trait HelloWorldModule extends scalalib.ScalaModule {
     override def scalaVersion = "3.0.2"
   }
 
-  def ideaJavaModuleFacets(ideaConfigVersion: Int): Command[Seq[JavaFacet]] =
-    T.command {
+  def ideaJavaModuleFacets(ideaConfigVersion: Int): Task[Seq[JavaFacet]] =
+    T.task {
       ideaConfigVersion match {
         case 4 =>
           Seq(
@@ -47,7 +47,7 @@ trait HelloWorldModule extends scalalib.ScalaModule {
 
   override def ideaConfigFiles(
       ideaConfigVersion: Int
-  ): Command[Seq[IdeaConfigFile]] = T.command {
+  ): Task[Seq[IdeaConfigFile]] = T.task {
     ideaConfigVersion match {
       case 4 =>
         Seq(
@@ -59,7 +59,7 @@ trait HelloWorldModule extends scalalib.ScalaModule {
           ),
           // components in project file
           IdeaConfigFile(
-            name = "compiler.xml",
+            os.sub / "compiler.xml",
             component = "AjcSettings",
             config = Seq(
               Element(
@@ -69,7 +69,7 @@ trait HelloWorldModule extends scalalib.ScalaModule {
             )
           ),
           IdeaConfigFile(
-            name = "compiler.xml",
+            os.sub / "compiler.xml",
             component = "CompilerConfiguration",
             config = Seq(
               Element(

main/resolve/src/mill/resolve/ParseArgs.scala

@@ -7,16 +7,6 @@ import mill.util.EitherOps
 
 import scala.annotation.tailrec
 
-sealed trait SelectMode
-object SelectMode {
-
-  /** All args are treated as targets or commands. If a `--` is detected, subsequent args are parameters to all commands. */
-  object Multi extends SelectMode
-
-  /** Like a combination of [[Single]] and [[Multi]], behaving like [[Single]] but using a special separator (`++`) to start parsing another target/command. */
-  object Separated extends SelectMode
-}
-
 object ParseArgs {
 
   type TargetsWithParams = (Seq[(Option[Segments], Segments)], Seq[String])

main/resolve/src/mill/resolve/SelectMode.scala

@@ -0,0 +1,12 @@
+package mill.resolve
+
+sealed trait SelectMode
+
+object SelectMode {
+
+  /** All args are treated as targets or commands. If a `--` is detected, subsequent args are parameters to all commands. */
+  object Multi extends SelectMode
+
+  /** Like a combination of [[Single]] and [[Multi]], behaving like [[Single]] but using a special separator (`++`) to start parsing another target/command. */
+  object Separated extends SelectMode
+}

runner/src/mill/runner/MillBuildBootstrap.scala

@@ -5,7 +5,6 @@ import mill.api.{PathRef, Val, internal}
 import mill.eval.Evaluator
 import mill.main.{RootModule, RunScript}
 import mill.resolve.SelectMode
-import mill.main.TokenReaders._
 import mill.define.{Discover, Segments}
 
 import java.net.URLClassLoader
@@ -292,7 +291,7 @@ object MillBuildBootstrap {
     // Copy the current location of the enclosing classes to `mill-launcher.jar`
     // if it has the wrong file extension, because the Zinc incremental compiler
     // doesn't recognize classpath entries without the proper file extension
-    val millLauncherOpt =
+    val millLauncherOpt: Option[os.Path] =
       if (
         os.isFile(selfClassLocation) &&
         !Set("zip", "jar", "class").contains(selfClassLocation.ext)

runner/src/mill/runner/MillBuildRootModule.scala

@@ -4,9 +4,9 @@ import coursier.Repository
 import mill._
 import mill.api.{Loose, PathRef, Result, internal}
 import mill.define.{Caller, Discover, Target, Task}
+import mill.scalalib.{BoundDep, Dep, DepSyntax, Lib, ScalaModule}
 import mill.util.CoursierSupport
 import mill.util.Util.millProjectModule
-import mill.scalalib.{BoundDep, DepSyntax, Lib, ScalaModule}
 import mill.scalalib.api.Versions
 import os.{Path, rel}
 import pprint.Util.literalize
@@ -55,7 +55,7 @@ class MillBuildRootModule()(implicit
       }
     }
 
-  override def scalaVersion = "2.13.10"
+  override def scalaVersion: T[String] = "2.13.10"
 
   def scriptSources = T.sources {
     MillBuildRootModule
@@ -152,7 +152,7 @@ class MillBuildRootModule()(implicit
     enclosingClasspath() ++ lineNumberPluginClasspath()
   }
 
-  override def scalacPluginIvyDeps = Agg(
+  override def scalacPluginIvyDeps: T[Agg[Dep]] = Agg(
     ivy"com.lihaoyi:::scalac-mill-moduledefs-plugin:${Versions.millModuledefsVersion}"
   )
 
@@ -222,7 +222,7 @@ object MillBuildRootModule {
       enclosingClasspath: Seq[os.Path],
       millTopLevelProjectRoot: os.Path,
       cliImports: Seq[String]
-  ) = {
+  ): Unit = {
     for (scriptSource <- scriptSources) {
       val relative = scriptSource.path.relativeTo(base)
       val dest = targetDest / FileImportGraph.fileImportToSegments(base, scriptSource.path, false)
@@ -253,8 +253,7 @@ object MillBuildRootModule {
       millTopLevelProjectRoot: os.Path,
       originalFilePath: os.Path,
       cliImports: Seq[String]
-  ) = {
-
+  ): String = {
     val superClass =
       if (pkg.size <= 1 && name == "build") "_root_.mill.main.RootModule"
       else {

scalalib/src/mill/scalalib/Dependency.scala

@@ -1,15 +1,19 @@
 package mill.scalalib
 
 import mill.T
-import mill.define.{Discover, ExternalModule}
+import mill.define.{Command, Discover, ExternalModule}
 import mill.eval.Evaluator
 import mill.main.EvaluatorTokenReader
 import mill.scalalib.dependency.DependencyUpdatesImpl
+import mill.scalalib.dependency.updates.ModuleDependenciesUpdates
 
 object Dependency extends ExternalModule {
 
   /** Calculate possible dependency updates. */
-  def updates(ev: Evaluator, allowPreRelease: Boolean = false) =
+  def updates(
+      ev: Evaluator,
+      allowPreRelease: Boolean = false
+  ): Command[Seq[ModuleDependenciesUpdates]] =
     T.command {
       DependencyUpdatesImpl(
         ev,
@@ -21,7 +25,7 @@ object Dependency extends ExternalModule {
     }
 
   /** Show possible dependency updates. */
-  def showUpdates(ev: Evaluator, allowPreRelease: Boolean = false) = T.command {
+  def showUpdates(ev: Evaluator, allowPreRelease: Boolean = false): Command[Unit] = T.command {
     DependencyUpdatesImpl.showAllUpdates(updates(ev, allowPreRelease)())
   }
 

scalalib/src/mill/scalalib/GenIdeaImpl.scala

@@ -236,7 +236,7 @@ case class GenIdeaImpl(
         os.sub / wf._1 -> ideaConfigElementTemplate(wf._2)
       }
 
-    type FileComponent = (SubPath, String)
+    type FileComponent = (SubPath, Option[String])
 
     /** Ensure, the additional configs don't collide. */
     def collisionFreeExtraConfigs(
@@ -262,7 +262,7 @@ case class GenIdeaImpl(
               )
             }
             val msg =
-              s"Config collision in file `${conf.name}` and component `${conf.component}`: ${details(
+              s"Config collision in file `${conf.subPath}` and component `${conf.component}`: ${details(
                   conf.config
                 )} vs. ${details(existing)}"
             ctx.map(_.log.error(msg))
@@ -274,7 +274,7 @@ case class GenIdeaImpl(
     val fileComponentContributions: Seq[(SubPath, Elem)] =
       collisionFreeExtraConfigs(configFileContributions).toSeq.map {
         case (file, configs) =>
-          val map: Map[String, Seq[GenIdeaModule.Element]] =
+          val map: Map[Option[String], Seq[GenIdeaModule.Element]] =
             configs
               .groupBy(_.component)
               .view
@@ -626,12 +626,12 @@ case class GenIdeaImpl(
   }
 
   def ideaConfigFileTemplate(
-      components: Map[String, Seq[GenIdeaModule.Element]]
+      components: Map[Option[String], Seq[GenIdeaModule.Element]]
   ): Elem = {
     <project version={"" + ideaConfigVersion}>
       {
       components.toSeq.map { case (name, config) =>
-        <component name={name}>{config.map(ideaConfigElementTemplate)}</component>
+        <component name={name.getOrElse("")}>{config.map(ideaConfigElementTemplate)}</component>
       }
     }
     </project>