Ability to programmatically define projects: Seq[Project]

[fommil]

With the new move to .sbt files, we will lack a key feature which is the ability to transform Seq[Project].

A typical usecase for this is when the build structure is generated (perhaps translated from another tool) and the owner of the sbt build scripts can only apply transformations to the Project object rather than edit the build.sbt directly.

I feel this is a blocker for 1.0.

[dwijnand]

@Duhemm has explored trying to port this in #2183.

I've needed access to .projects to solve the use case details in http://stackoverflow.com/a/31061013/463761.

Also I think this might be a blocker for https://github.com/sbt/sbt-pom-reader.

[fommil]

That's interesting. It is explicitly read-only, but this ticket is to allow the "mutation" of Seq[Project].

Somewhat related is the ability to specify / select the rootProject from the transformed Seq[Project].

[dwijnand]

Yes, that pull requested morphed into read-only.

But I'm agreeing with you, there are use-cases that require programmatically defining projects, for which, to my knowledge, there's no facility currently in 1.0.

[fommil]

@eed3si9n can this please be considered for 1.0? This one really is a blocker for me at work in moving to 1.0.

[SethTisue]

for MiMa to convert to build.sbt style is blocked by this; the MiMa build generates test projects on the fly (one per subdirectory of reporter/functional-tests/src/test) and then adds them to the build via override lazy val projects = ...

[fommil]

Nice! I'll try this out sometime

[dwijnand]

@fommil It'll be part of 0.13.13 (and available in the 0.13.13-RC2 pre-release)

[SethTisue]

@dwijnand to help you test the fix, could I interest you in submitting a PR upgrading MiMa to use 0.13.13-RCx and addressing https://github.com/typesafehub/migration-manager/blob/7c956c57ae137dbfc729db54f5d35d33b9436347/project/Build.scala#L85-L87?

“to help you”, my god, how transparent. see, it's all about you

[dwijnand]

Sure.

[Atry]

Is there a corresponding DslEntry for extraProjects method?

[Atry]

aggregate and dependsOn is similar, however they always error for inline projects:

dependsOn(Project("aaa", file("yyy")), Project("xxx2", file("yyy2")))

java.lang.RuntimeException: No project 'aaa' in 'file:/private/tmp/xxx/'.
Valid project IDs: xxx
	at scala.sys.package$.error(package.scala:27)
	at sbt.Load$$anonfun$checkAll$2$$anonfun$apply$16.apply(Load.scala:401)
	at sbt.Load$$anonfun$checkAll$2$$anonfun$apply$16.apply(Load.scala:396)
	at scala.collection.immutable.List.foreach(List.scala:318)
	at sbt.Load$$anonfun$checkAll$2.apply(Load.scala:396)
	at sbt.Load$$anonfun$checkAll$2.apply(Load.scala:396)
	at scala.collection.TraversableLike$WithFilter$$anonfun$foreach$1.apply(TraversableLike.scala:772)
	at scala.collection.immutable.Map$Map1.foreach(Map.scala:109)
	at scala.collection.TraversableLike$WithFilter.foreach(TraversableLike.scala:771)
	at sbt.Load$.checkAll(Load.scala:396)
	at sbt.Load$.loadURI(Load.scala:321)
	at sbt.Load$.load(Load.scala:316)
	at sbt.Load$.load(Load.scala:305)
	at sbt.Load$$anonfun$4.apply(Load.scala:146)
	at sbt.Load$$anonfun$4.apply(Load.scala:146)
	at sbt.Load$.timed(Load.scala:1025)
	at sbt.Load$.apply(Load.scala:146)
	at sbt.Load$.defaultLoad(Load.scala:39)
	at sbt.BuiltinCommands$.liftedTree1$1(Main.scala:496)
	at sbt.BuiltinCommands$.doLoadProject(Main.scala:496)
	at sbt.BuiltinCommands$$anonfun$loadProjectImpl$2.apply(Main.scala:488)
	at sbt.BuiltinCommands$$anonfun$loadProjectImpl$2.apply(Main.scala:488)
	at sbt.Command$$anonfun$applyEffect$1$$anonfun$apply$2.apply(Command.scala:59)
	at sbt.Command$$anonfun$applyEffect$1$$anonfun$apply$2.apply(Command.scala:59)
	at sbt.Command$$anonfun$applyEffect$2$$anonfun$apply$3.apply(Command.scala:61)
	at sbt.Command$$anonfun$applyEffect$2$$anonfun$apply$3.apply(Command.scala:61)
	at sbt.Command$.process(Command.scala:93)
	at sbt.MainLoop$$anonfun$1$$anonfun$apply$1.apply(MainLoop.scala:96)
	at sbt.MainLoop$$anonfun$1$$anonfun$apply$1.apply(MainLoop.scala:96)
	at sbt.State$$anon$1.process(State.scala:184)
	at sbt.MainLoop$$anonfun$1.apply(MainLoop.scala:96)
	at sbt.MainLoop$$anonfun$1.apply(MainLoop.scala:96)
	at sbt.ErrorHandling$.wideConvert(ErrorHandling.scala:17)
	at sbt.MainLoop$.next(MainLoop.scala:96)
	at sbt.MainLoop$.run(MainLoop.scala:89)
	at sbt.MainLoop$$anonfun$runWithNewLog$1.apply(MainLoop.scala:68)
	at sbt.MainLoop$$anonfun$runWithNewLog$1.apply(MainLoop.scala:63)
	at sbt.Using.apply(Using.scala:24)
	at sbt.MainLoop$.runWithNewLog(MainLoop.scala:63)
	at sbt.MainLoop$.runAndClearLast(MainLoop.scala:46)
	at sbt.MainLoop$.runLoggedLoop(MainLoop.scala:30)
	at sbt.MainLoop$.runLogged(MainLoop.scala:22)
	at sbt.StandardMain$.runManaged(Main.scala:57)
	at sbt.xMain.run(Main.scala:29)
	at xsbt.boot.Launch$$anonfun$run$1.apply(Launch.scala:109)
	at xsbt.boot.Launch$.withContextLoader(Launch.scala:128)
	at xsbt.boot.Launch$.run(Launch.scala:109)
	at xsbt.boot.Launch$$anonfun$apply$1.apply(Launch.scala:35)
	at xsbt.boot.Launch$.launch(Launch.scala:117)
	at xsbt.boot.Launch$.apply(Launch.scala:18)
	at xsbt.boot.Boot$.runImpl(Boot.scala:41)
	at xsbt.boot.Boot$.main(Boot.scala:17)
	at xsbt.boot.Boot.main(Boot.scala)