collapse boilerplate folder structure within src/ folders (#505)

* collapse boilerplate folder structure within src/ folders

* .

1 files changed, 117 insertions, 0 deletions

diff --git a/scalalib/src/publish/Pom.scala b/scalalib/src/publish/Pom.scala
new file mode 100644
index 00000000..57a0e196
--- /dev/null
+++ b/scalalib/src/publish/Pom.scala
@@ -0,0 +1,117 @@
+package mill.scalalib.publish
+
+import mill.util.Loose.Agg
+
+import scala.xml.{Atom, Elem, NodeSeq, PrettyPrinter}
+
+object Pom {
+
+  val head = "<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n"
+
+  implicit class XmlOps(val e: Elem) extends AnyVal {
+    // source: https://stackoverflow.com/a/5254068/449071
+    def optional : NodeSeq = {
+      require(e.child.length == 1)
+      e.child.head match {
+        case atom: Atom[Option[_]] => atom.data match {
+          case None    => NodeSeq.Empty
+          case Some(x) => e.copy(child = x match {
+            case n: NodeSeq => n
+            case x => new Atom(x)
+          })
+        }
+        case _ => e
+      }
+    }
+  }
+
+  //TODO - not only jar packaging support?
+  def apply(artifact: Artifact,
+            dependencies: Agg[Dependency],
+            name: String,
+            pomSettings: PomSettings): String = {
+    val xml =
+      <project
+        xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd"
+        xmlns:xsi ="http://www.w3.org/2001/XMLSchema-instance"
+        xmlns ="http://maven.apache.org/POM/4.0.0">
+
+        <modelVersion>4.0.0</modelVersion>
+        <name>{name}</name>
+        <groupId>{artifact.group}</groupId>
+        <artifactId>{artifact.id}</artifactId>
+        <packaging>jar</packaging>
+        <description>{pomSettings.description}</description>
+
+        <version>{artifact.version}</version>
+        <url>{pomSettings.url}</url>
+        <licenses>
+          {pomSettings.licenses.map(renderLicense)}
+        </licenses>
+        <scm>
+          { <connection>{pomSettings.versionControl.connection}</connection>.optional }
+          { <developerConnection>{pomSettings.versionControl.developerConnection}</developerConnection>.optional }
+          { <tag>{pomSettings.versionControl.tag}</tag>.optional }
+          { <url>{pomSettings.versionControl.browsableRepository}</url>.optional }
+        </scm>
+        <developers>
+          {pomSettings.developers.map(renderDeveloper)}
+        </developers>
+        <dependencies>
+          {dependencies.map(renderDependency).toSeq}
+        </dependencies>
+      </project>
+
+    val pp = new PrettyPrinter(120, 4)
+    head + pp.format(xml)
+  }
+
+  private def renderLicense(l: License): Elem = {
+    <license>
+      <name>{l.name}</name>
+      <url>{l.url}</url>
+      <distribution>{l.distribution}</distribution>
+    </license>
+  }
+
+  private def renderDeveloper(d: Developer): Elem = {
+    <developer>
+      <id>{d.id}</id>
+      <name>{d.name}</name>
+      { <organization>{d.organization}</organization>.optional }
+      { <organizationUrl>{d.organizationUrl}</organizationUrl>.optional }
+    </developer>
+  }
+
+  private def renderDependency(d: Dependency): Elem = {
+    val scope = d.scope match {
+      case Scope.Compile  => NodeSeq.Empty
+      case Scope.Provided => <scope>provided</scope>
+      case Scope.Test     => <scope>test</scope>
+      case Scope.Runtime  => <scope>runtime</scope>
+    }
+    if (d.exclusions.isEmpty)
+      <dependency>
+        <groupId>{d.artifact.group}</groupId>
+        <artifactId>{d.artifact.id}</artifactId>
+        <version>{d.artifact.version}</version>
+        {scope}
+      </dependency>
+    else
+      <dependency>
+        <groupId>{d.artifact.group}</groupId>
+        <artifactId>{d.artifact.id}</artifactId>
+        <version>{d.artifact.version}</version>
+        <exclusions>
+          {d.exclusions.map(ex =>
+            <exclusion>
+              <groupId>{ex._1}</groupId>
+              <artifactId>{ex._2}</artifactId>
+            </exclusion>
+          )}
+        </exclusions>
+        {scope}
+      </dependency>
+  }
+
+}