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`Args` API to model a CLI args data structure that supports mapping of path roots
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| //| mill-version: 1.0.6 | |
| package build | |
| import mill.* | |
| import mill.api.* | |
| import scala.annotation.targetName | |
| case class Args (value: Seq[ArgGroup]) derives upickle.ReadWriter { | |
| def toStringSeq: Seq[String] = value.map(_.toString) | |
| override def toString(): String = value.mkString("Args(", ", ", ")") | |
| } | |
| object Args { | |
| @targetName("applyUnion") | |
| def apply(value: (Arg|ArgGroup|Seq[Arg])*): Args = Args(value.flatMap { | |
| case a: Arg => Seq(ArgGroup(a)) | |
| case a: ArgGroup => Seq(a) | |
| case s: Seq[Arg] => s.map(ArgGroup(_)) | |
| }) | |
| } | |
| /** | |
| * A set of args, which are use as one | |
| * @param value | |
| */ | |
| case class ArgGroup private (value: Seq[Arg]) derives upickle.ReadWriter { | |
| override def toString(): String = value.mkString("(", ", ", ")") | |
| } | |
| type ArgTypes = (String|os.Path) | |
| object ArgGroup { | |
| @targetName("applyUnion") | |
| def apply(value: (Arg | Seq[Arg])*): ArgGroup = ArgGroup(value.flatMap { | |
| case a: Arg => Seq(a) | |
| case s: Seq[Arg] => s | |
| }) | |
| def when(cond: Boolean)(value: Arg*): ArgGroup = if(cond) ArgGroup(value*) else ArgGroup() | |
| given argsToArgGroup: Conversion[(ArgTypes,ArgTypes), ArgGroup] = | |
| (tuple: (ArgTypes, ArgTypes)) => ArgGroup(Arg(tuple._1), Arg(tuple._2)) | |
| } | |
| case class Arg (value: (ArgTypes)*) { | |
| override def toString: String = value.mkString("") | |
| } | |
| object Arg { | |
| implicit def jsonReadWriter: upickle.ReadWriter[Arg] = upickle.readwriter[Seq[(Option[String], Option[os.Path])]].bimap( | |
| _.value.map { | |
| case path: os.Path => (None, Some(path)) | |
| case str: String => (Some(str), None) | |
| }, | |
| seq => Arg(seq.map { | |
| case (Some(str), _) => str | |
| case (_, Some(path)) => path | |
| }*) | |
| ) | |
| given stringToArg: Conversion[String, Arg] = (value: String) => Arg(value) | |
| given osPathToArg: Conversion[os.Path, Arg] = (value: os.Path) => Arg(value) | |
| } | |
| implicit class ArgPartsSyntax(ctx: StringContext) extends AnyVal { | |
| def arg(args: Any*): Arg = { | |
| val vals = ctx.parts.take(args.length).zip(args).flatMap { case (p, a) => Seq(p, a) } ++ | |
| ctx.parts.drop(args.length) | |
| val elems: Seq[(String|os.Path)] = vals.flatMap { | |
| case path: os.Path => Seq(path) | |
| case s => Seq(s.toString).filter(_.nonEmpty) | |
| } | |
| Arg(elems*) | |
| } | |
| } | |
| object `package` extends Module { | |
| def sources: T[Seq[PathRef]] = Task { | |
| Seq(PathRef(moduleDir / "src/File1.java"), PathRef(moduleDir / "src/File2.java")) | |
| } | |
| def sources2: T[Seq[PathRef]] = Task { | |
| Seq(PathRef(moduleDir / "src/File3.java"), PathRef(moduleDir / "src/File4.java")) | |
| } | |
| def plugin: T[PathRef] = Task { | |
| PathRef(moduleDir / "lib/plugin.jar") | |
| } | |
| def javacOptions: Task.Simple[Args] = Args( | |
| // single arg | |
| Arg("-deprecation"), | |
| // implicit single args | |
| "-verbose", | |
| // two args as group | |
| ArgGroup("--release", "17"), | |
| // two args as tuple | |
| ("--release", "17"), | |
| // an option including a file via ArgParts | |
| Arg("-Xplugin=", plugin().path), | |
| // an option including a file via arg string interpolator | |
| arg"-Xplugin:${plugin().path}", | |
| // some files | |
| sources().map(_.path), | |
| // some files as ArgGroup | |
| ArgGroup(sources2().map(_.path)*), | |
| // Mixed ArgGroup | |
| ArgGroup("--extra", arg"-Xplugin=${plugin().path}", sources().map(_.path)) | |
| ) | |
| def useOptions() = Task.Command { | |
| val opts = javacOptions() | |
| println(s"options: ${opts}") | |
| pprint.log(upickle.write(opts)) | |
| } | |
| } |
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Related to
out/-path: com-lihaoyi/mill#3660This gits can be run with Mill 1.0.6 to show that it can be used as drop-in replacement for
Seq[String]to encode options in Mill tasks:When used with a local build based on PR com-lihaoyi/mill#6031, you can see, that all paths are properly represented with placeholders (here
$WORKSPACE) to their mapped root paths.