In SBT, how does one `addCompilerPlugin` from Git? - sbt

Question

Normally, when not using Git, you can just write:
addCompilerPlugin("something" % "blah" ...)
scalacOptions += "-P:blah:..."
This addCompilerPlugin takes a ModuleID. But here... I've tried adding:
lazy val root = project in file(".") dependsOn
uri("git://github.com/puffnfresh/wartremover.git#master")
to the project/plugins.sbt as well as:
lazy val wartRemover = RootProject(
uri("git://github.com/puffnfresh/wartremover.git#master"))
lazy val root = Project(...).settings(
...
scalacOptions += "-P:wartremover:...",
...
) depends on wartRemover
Both result in:
[error] (root/*:update) sbt.ResolveException: unresolved dependency:
org.brianmckenna#wartremover_2.10.3;0.5-SNAPSHOT: not found

Answer 1

tl;dr The project wartremover has not been published for Scala version 2.10.3. Downgrade yours with the following in build.sbt among the other necessary settings:
scalaVersion := "2.10.2"
Detailed procedure focusing on Scala 2.10.3
The following in build.sbt
addCompilerPlugin("org.brianmckenna" % "wartremover" % "0.5" cross CrossVersion.full)
adds org.brianmckenna:wartremover:0.5:plugin->default(compile) to libraryDependencies.
[sbt-0-13-2]> show libraryDependencies
[info] List(org.scala-lang:scala-library:2.10.3, org.brianmckenna:wartremover:0.5:plugin->default(compile))
So to use a RootProject that points at the project wartremover at GitHub I had to use the following in build.sbt (this is the complete file):
scalacOptions in root += "-P:wartremover:traverser:org.brianmckenna.wartremover.warts.Unsafe"
lazy val root = project in file(".") dependsOn wartRemover % "plugin->default(compile)"
lazy val wartRemover = RootProject(
uri("git://github.com/puffnfresh/wartremover.git#master"))
Since the project wartremover is not published for 2.10.3 I followed the steps below:
Show available projects
[root]> projects
[info] In file:/Users/jacek/sandbox/so/sbt-0.13.2/
[info] * root
[info] In git://github.com/puffnfresh/wartremover.git#master
[info] wartremover
Switch to wartremover and publishLocal it for scalaVersion set to 2.10.3.
[wartremover]> set scalaVersion := "2.10.3"
[info] Defining wartremover/*:scalaVersion
[info] The new value will be used by wartremover/*:allDependencies, wartremover/*:assemblyPackageScala::assemblyDefaultJarName and 12 others.
[info] Run `last` for details.
[info] Reapplying settings...
[info] Set current project to wartremover (in build git://github.com/puffnfresh/wartremover.git#master)
[wartremover]> publishLocal
[info] Packaging /Users/jacek/.sbt/0.13/staging/d6dd3d2e3d818e69943a/wartremover/target/scala-2.10/wartremover_2.10.3-0.6-SNAPSHOT-sources.jar ...
[info] Updating {git://github.com/puffnfresh/wartremover.git#master}wartremover...
...
[info] published ivy to /Users/jacek/.ivy2/local/org.brianmckenna/wartremover_2.10.3/0.6-SNAPSHOT/ivys/ivy.xml
[success] Total time: 7 s, completed Jan 18, 2014 11:34:07 PM
Switch to the project root and do update. It should now work fine.
[wartremover]> project {file:/Users/jacek/sandbox/so/sbt-0.13.2/}
[info] Set current project to root (in build file:/Users/jacek/sandbox/so/sbt-0.13.2/)
[root]> update
[info] Updating {file:/Users/jacek/sandbox/so/sbt-0.13.2/}root...
[info] Resolving org.fusesource.jansi#jansi;1.4 ...
[info] Done updating.
[success] Total time: 0 s, completed Jan 18, 2014 11:36:24 PM
console should work fine now, too.
[root]> console
[info] Starting scala interpreter...
[info]
<console>:5: error: var is disabled
var value: scala.tools.nsc.interpreter.IMain = _
^
Welcome to Scala version 2.10.3 (Java HotSpot(TM) 64-Bit Server VM, Java 1.7.0_45).
Type in expressions to have them evaluated.
Type :help for more information.
scala>
The error message worries me, though. I don't know the plugin and neither do I know how to get rid of it. It also happens when I follow the steps described in Compiler plugin when scalaVersion := "2.10.2" is set in build.sbt (so the compiler plugin's available in the repo).