Don't leave POMs as artifacts in update reports

sbt-pack isn't too fine with those in particular

sbt-coursier/src/main/scala-2.10/coursier/ToSbt.scala

@@ -96,14 +96,23 @@ object ToSbt {
   def moduleReports(
     res: Resolution,
     classifiersOpt: Option[Seq[String]],
-    artifactFileOpt: (Module, String, Artifact) => Option[File]
+    artifactFileOpt: (Module, String, Artifact) => Option[File],
+    keepPomArtifact: Boolean = false
   ) = {
-    val depArtifacts =
+    val depArtifacts0 =
       classifiersOpt match {
         case None => res.dependencyArtifacts
         case Some(cl) => res.dependencyClassifiersArtifacts(cl)
       }
 
+    val depArtifacts =
+      if (keepPomArtifact)
+        depArtifacts0
+      else
+        depArtifacts0.filter {
+          case (_, a) => a.attributes != Attributes("pom", "")
+        }
+
     val groupedDepArtifacts = grouped(depArtifacts)
 
     val versions = res.dependencies.toVector.map { dep =>
@@ -155,7 +164,8 @@ object ToSbt {
     resolution: Resolution,
     configs: Map[String, Set[String]],
     classifiersOpt: Option[Seq[String]],
-    artifactFileOpt: (Module, String, Artifact) => Option[File]
+    artifactFileOpt: (Module, String, Artifact) => Option[File],
+    keepPomArtifact: Boolean = false
   ): sbt.UpdateReport = {
 
     val configReports = configs.map {
@@ -163,7 +173,7 @@ object ToSbt {
         val configDeps = extends0.flatMap(configDependencies.getOrElse(_, Nil))
         val subRes = resolution.subset(configDeps)
 
-        val reports = ToSbt.moduleReports(subRes, classifiersOpt, artifactFileOpt)
+        val reports = ToSbt.moduleReports(subRes, classifiersOpt, artifactFileOpt, keepPomArtifact)
 
         new ConfigurationReport(
           config,

sbt-coursier/src/sbt-test/sbt-coursier/no-pom-artifact/build.sbt

@@ -0,0 +1,28 @@
+
+lazy val noPomCheck = TaskKey[Unit]("noPomCheck")
+
+noPomCheck := {
+
+  val configReport = update.value
+    .configuration("compile")
+    .getOrElse {
+      throw new Exception(
+        "compile configuration not found in update report"
+      )
+    }
+
+  val artifacts = configReport
+    .modules
+    .flatMap(_.artifacts)
+    .map(_._1)
+
+  val pomArtifacts = artifacts
+    .filter { a =>
+      a.`type` == "pom" && a.classifier.isEmpty
+    }
+
+  for (a <- pomArtifacts)
+    streams.value.log.error(s"Found POM artifact $a")
+
+  assert(pomArtifacts.isEmpty)
+}

sbt-coursier/src/sbt-test/sbt-coursier/no-pom-artifact/project/plugins.sbt

@@ -0,0 +1,11 @@
+{
+  val pluginVersion = sys.props.getOrElse(
+    "plugin.version",
+    throw new RuntimeException(
+      """|The system property 'plugin.version' is not defined.
+         |Specify this property using the scriptedLaunchOpts -D.""".stripMargin
+    )
+  )
+
+  addSbtPlugin("io.get-coursier" % "sbt-coursier" % pluginVersion)
+}

sbt-coursier/src/sbt-test/sbt-coursier/no-pom-artifact/test

@@ -0,0 +1 @@
+> noPomCheck