SPARK-2899 Doc generation is back to working in new SBT Build.

The reason for this bug was introduciton of OldDeps project. It had to be excluded to prevent unidocs from trying to put it on "docs compile" classpath.

Author: Prashant Sharma <prashant.s@imaginea.com>

Closes #1830 from ScrapCodes/doc-fix and squashes the following commits:

e5d52e6 [Prashant Sharma] SPARK-2899 Doc generation is back to working in new SBT Build.

project/SparkBuild.scala

@@ -30,11 +30,11 @@ object BuildCommons {
 
   private val buildLocation = file(".").getAbsoluteFile.getParentFile
 
-  val allProjects@Seq(bagel, catalyst, core, graphx, hive, hiveThriftServer, mllib, repl, spark,
+  val allProjects@Seq(bagel, catalyst, core, graphx, hive, hiveThriftServer, mllib, repl,
   sql, streaming, streamingFlumeSink, streamingFlume, streamingKafka, streamingMqtt,
   streamingTwitter, streamingZeromq) =
     Seq("bagel", "catalyst", "core", "graphx", "hive", "hive-thriftserver", "mllib", "repl",
-      "spark", "sql", "streaming", "streaming-flume-sink", "streaming-flume", "streaming-kafka",
+      "sql", "streaming", "streaming-flume-sink", "streaming-flume", "streaming-kafka",
       "streaming-mqtt", "streaming-twitter", "streaming-zeromq").map(ProjectRef(buildLocation, _))
 
   val optionallyEnabledProjects@Seq(yarn, yarnStable, yarnAlpha, java8Tests, sparkGangliaLgpl, sparkKinesisAsl) =
@@ -44,8 +44,9 @@ object BuildCommons {
   val assemblyProjects@Seq(assembly, examples) = Seq("assembly", "examples")
     .map(ProjectRef(buildLocation, _))
 
-  val tools = "tools"
-
+  val tools = ProjectRef(buildLocation, "tools")
+  // Root project.
+  val spark = ProjectRef(buildLocation, "spark")
   val sparkHome = buildLocation
 }
 
@@ -126,26 +127,6 @@ object SparkBuild extends PomBuild {
     publishLocalBoth <<= Seq(publishLocal in MavenCompile, publishLocal).dependOn
   )
 
-  /** Following project only exists to pull previous artifacts of Spark for generating
-    Mima ignores. For more information see: SPARK 2071 */
-  lazy val oldDeps = Project("oldDeps", file("dev"), settings = oldDepsSettings)
-
-  def versionArtifact(id: String): Option[sbt.ModuleID] = {
-    val fullId = id + "_2.10"
-    Some("org.apache.spark" % fullId % "1.0.0")
-  }
-
-  def oldDepsSettings() = Defaults.defaultSettings ++ Seq(
-    name := "old-deps",
-    scalaVersion := "2.10.4",
-    retrieveManaged := true,
-    retrievePattern := "[type]s/[artifact](-[revision])(-[classifier]).[ext]",
-    libraryDependencies := Seq("spark-streaming-mqtt", "spark-streaming-zeromq",
-      "spark-streaming-flume", "spark-streaming-kafka", "spark-streaming-twitter",
-      "spark-streaming", "spark-mllib", "spark-bagel", "spark-graphx",
-      "spark-core").map(versionArtifact(_).get intransitive())
-  )
-
   def enable(settings: Seq[Setting[_]])(projectRef: ProjectRef) = {
     val existingSettings = projectsMap.getOrElse(projectRef.project, Seq[Setting[_]]())
     projectsMap += (projectRef.project -> (existingSettings ++ settings))
@@ -184,7 +165,7 @@ object SparkBuild extends PomBuild {
     super.projectDefinitions(baseDirectory).map { x =>
       if (projectsMap.exists(_._1 == x.id)) x.settings(projectsMap(x.id): _*)
       else x.settings(Seq[Setting[_]](): _*)
-    } ++ Seq[Project](oldDeps)
+    } ++ Seq[Project](OldDeps.project)
   }
 
 }
@@ -193,6 +174,31 @@ object Flume {
   lazy val settings = sbtavro.SbtAvro.avroSettings
 }
 
+/**
+ * Following project only exists to pull previous artifacts of Spark for generating
+ * Mima ignores. For more information see: SPARK 2071
+ */
+object OldDeps {
+
+  lazy val project = Project("oldDeps", file("dev"), settings = oldDepsSettings)
+
+  def versionArtifact(id: String): Option[sbt.ModuleID] = {
+    val fullId = id + "_2.10"
+    Some("org.apache.spark" % fullId % "1.0.0")
+  }
+
+  def oldDepsSettings() = Defaults.defaultSettings ++ Seq(
+    name := "old-deps",
+    scalaVersion := "2.10.4",
+    retrieveManaged := true,
+    retrievePattern := "[type]s/[artifact](-[revision])(-[classifier]).[ext]",
+    libraryDependencies := Seq("spark-streaming-mqtt", "spark-streaming-zeromq",
+      "spark-streaming-flume", "spark-streaming-kafka", "spark-streaming-twitter",
+      "spark-streaming", "spark-mllib", "spark-bagel", "spark-graphx",
+      "spark-core").map(versionArtifact(_).get intransitive())
+  )
+}
+
 object Catalyst {
   lazy val settings = Seq(
     addCompilerPlugin("org.scalamacros" % "paradise" % "2.0.1" cross CrossVersion.full),
@@ -285,9 +291,9 @@ object Unidoc {
     publish := {},
 
     unidocProjectFilter in(ScalaUnidoc, unidoc) :=
-      inAnyProject -- inProjects(repl, examples, tools, catalyst, yarn, yarnAlpha),
+      inAnyProject -- inProjects(OldDeps.project, repl, examples, tools, catalyst, yarn, yarnAlpha),
     unidocProjectFilter in(JavaUnidoc, unidoc) :=
-      inAnyProject -- inProjects(repl, bagel, graphx, examples, tools, catalyst, yarn, yarnAlpha),
+      inAnyProject -- inProjects(OldDeps.project, repl, bagel, graphx, examples, tools, catalyst, yarn, yarnAlpha),
 
     // Skip class names containing $ and some internal packages in Javadocs
     unidocAllSources in (JavaUnidoc, unidoc) := {

project/plugins.sbt

@@ -23,6 +23,6 @@ addSbtPlugin("com.typesafe" % "sbt-mima-plugin" % "0.1.6")
 
 addSbtPlugin("com.alpinenow" % "junit_xml_listener" % "0.5.1")
 
-addSbtPlugin("com.eed3si9n" % "sbt-unidoc" % "0.3.0")
+addSbtPlugin("com.eed3si9n" % "sbt-unidoc" % "0.3.1")
 
 addSbtPlugin("com.cavorite" % "sbt-avro" % "0.3.2")