如何拥有具有多个 Scala 版本的 SBT 子项目

Question

我有一个使用 Scala 2.10 的项目和一个使用 Scala 2.11 的项目。它们依赖于一个公共项目，该项目可以使用两者进行编译。

lazy val foo = (project in file("foo")).dependsOn(baz).settings(
  scalaVersion := "2.10.4"
)
lazy val bar = (project in file("bar")).dependsOn(baz).settings(
  scalaVersion := "2.11.4"
)
lazy val baz = (project in file("baz")).settings(
  crossScalaVersions := Seq("2.10.4", "2.11.4"),
  scalaVersion := "2.10.4"
)

然后

$ sbt bar/update
[info] Updating {file:/home/paul/Private/test/}bar...
[info] Resolving baz#baz_2.11;0.1-SNAPSHOT ...
[warn]  module not found: baz#baz_2.11;0.1-SNAPSHOT
[warn] ==== local: tried
[warn]   /home/paul/.ivy2/local/baz/baz_2.11/0.1-SNAPSHOT/ivys/ivy.xml
[warn] ==== public: tried
[warn]   http://repo1.maven.org/maven2/baz/baz_2.11/0.1-SNAPSHOT/baz_2.11-0.1-SNAPSHOT.pom
[info] Resolving jline#jline;2.12 ...
[warn]  ::::::::::::::::::::::::::::::::::::::::::::::
[warn]  ::          UNRESOLVED DEPENDENCIES         ::
[warn]  ::::::::::::::::::::::::::::::::::::::::::::::
[warn]  :: baz#baz_2.11;0.1-SNAPSHOT: not found
[warn]  ::::::::::::::::::::::::::::::::::::::::::::::
[trace] Stack trace suppressed: run last bar/*:update for the full output.
[error] (bar/*:update) sbt.ResolveException: unresolved dependency: baz#baz_2.11;0.1-SNAPSHOT: not found
[error] Total time: 1 s, completed Jan 13, 2015 11:42:51 AM

如何让两个项目都baz可用？

Answer 1

Yevgeniy Mordovkin提出的解决方案，在baz项目中声明crossPaths := false，有效。

您可以做的另一件事是在命令之前加上一个+：sbt '+ bar/update' 。这将为所有声明的 Scala 版本构建 baz。

Answer 2

我为此创建了一个 SBT 插件。

project/plugins.sbt

resolvers += Resolver.sonatypeRepo("releases")
addSbtPlugin("com.lucidchart" % "sbt-cross" % "1.0")

build.sbt

lazy val foo = (project in file("foo")).dependsOn(baz_2_10).settings(
  scalaVersion := "2.10.4"
)
lazy val bar = (project in file("bar")).dependsOn(baz_2_11).settings(
  scalaVersion := "2.11.5"
)
lazy val baz = (project in file("baz")).cross
lazy val baz_2_10 = baz("2.10.4")
lazy val baz_2_11 = baz("2.11.5")

这需要多几行，但现在一切都按预期编译：sbt foo/compile有效，sbt bar/compile有效。

你

不必记住唯一的命令，你没有来自crossPath := false的错误，并且与++不同，这是可并行化的：sbt compile将同时编译foo、bar和baz正确的Scala版本。

Answer 3

我有一个类似的设置，并让它像这样工作：

lazy val baz = (project in file("baz")).settings(
  crossScalaVersions := Seq("2.10.4", "2.11.4")
)
lazy val bar = (project in file("bar")).dependsOn(baz).settings(
  scalaVersion := "2.10.4"
)
lazy val foo = (project in file("foo")).dependsOn(baz).settings(
  scalaVersion := "2.11.4"
)

并用

sbt '++ 2.10.4 baz/compile' 'bar/compile' '++ 2.11.4 baz/compile' 'foo/compile'