Why does publishing plugin project fail with RuntimeException: Repository for publishing is not specified? - sbt

Question

I am trying to publish an SBT plugin to a repository. I'm not sure if this has any relevance, but our plugin loads the sbt-twirl plugin - Googling around, it seems like publishConfiguration might be overriden:
new PublishConfiguration(None, "dotM2", arts, Seq(), level)
When I run the publish task, artifacts are deployed to the repo, but the sbt task then fails:
sbt (my-sbt-plugin)> publish
[info] Loading global plugins from ...
...
[info] Done packaging.
[info] published sbt-my-sbt-plugin to http://my.repo.com/.../sbt-my-sbt-plugin-0.1-SNAPSHOT.jar
java.lang.RuntimeException: Repository for publishing is not specified.
.... stack trace here ....
[error] (my-sbt-plugin/*:publishConfiguration) Repository for publishing is not specified.
What is causing the error, and what could I do to stop the publishing from failing?
** Update ** Here is inspect publish
sbt (my-sbt-plugin)> inspect publish
[info] Task: Unit
[info] Description:
[info] Publishes artifacts to a repository.
[info] Provided by:
[info] {file:/path/to/my-sbt-plugin/}my-sbt-plugin/*:publish
[info] Defined at:
[info] (sbt.Classpaths) Defaults.scala:988
[info] Dependencies:
[info] my-sbt-plugin/*:ivyModule
[info] my-sbt-plugin/*:publishConfiguration
[info] my-sbt-plugin/*:publish::streams
[info] Delegates:
[info] my-sbt-plugin/*:publish
[info] {.}/*:publish
[info] */*:publish
[info] Related:
[info] plugin/*:publish
Here's how I've configured publishing (with some of the plugin settings, excluding libraryDependencies and 1 or 2 other settings)
lazy val plugin = project
.settings(publishSbtPlugin: _*)
.settings(
name := "my-sbt-plugin",
sbtPlugin := true,
addSbtPlugin("com.typesafe.sbt" % "sbt-twirl" % "1.0.2")
)
def publishSbtPlugin = Seq(
publishMavenStyle := true,
publishTo := {
val myrepo = "http://myrepo.tld/"
if (isSnapshot.value) Some("The Realm" at myrepo + "snapshots")
else Some("The Realm" at myrepo + "releases")
},
credentials += Credentials(Path.userHome / ".ivy2" / ".credentials")
)

Answer 1

tl;dr Don't use lazy val plugin = project to define a project (for unknown yet reasons)
After few comments it turned out that the issue was that the name of the project plugin as defined using lazy val plugin = project. It seems that the name is somehow reserved. Change the project's name to any other name than plugin and start over.

Answer 2

Specifying a project name other than "plugin" resolved the issue. I simplified the build definition a bit by removing a redundant build.sbt in 1 of the projects and am just using a full build definition in project directory. The root project that hosts the multi-project build is also reconfigured for no publishing:
lazy val root =
Project("sbt-my-plugin-root", file("."))
.settings(noPublishing: _*)
.aggregate(sbtMyPluginModule)
lazy val sbtMyPluginModule =
Project("sbt-my-plugin-module", file("sbt-my-plugin-module"))
.settings(publishSbtPlugin: _*)
.settings(
name := "sbt-my-plugin-module",
organization := "com.my.org",
sbtPlugin := true
)
lazy val noPublishing = seq(
publish := (),
publishLocal := ()
)
lazy val publishSbtPlugin = Seq(
publishMavenStyle := true,
publishArtifact in Test := false,
publishTo := {
val myrepo = "http://myrepo.tld/"
if (isSnapshot.value) Some("The Realm" at myrepo + "snapshots")
else Some("The Realm" at myrepo + "releases")
},
credentials += Credentials(Path.userHome / ".ivy2" / ".credentials")
)

Answer 3

if you trying this on your local then use publishLocal (not publish) as follows:
sbt clean compile publish-local