help: alignment and add tasks

main/CommandSupport.scala

@@ -33,6 +33,7 @@ object CommandSupport
 	/** The prefix used to identify a request to execute the remaining input on source changes.*/
 	val ContinuousExecutePrefix = "~"
 	val HelpCommand = "help"
+	val TasksCommand = "tasks"
 	val ProjectCommand = "project"
 	val ProjectsCommand = "projects"
 
@@ -108,6 +109,15 @@ SetCommand + """ <setting-expression>
 
 	def continuousBriefHelp = (ContinuousExecutePrefix + " <action>", "Executes the specified command whenever source files change.")
 
+	def tasksPreamble = """
+This is a list of tasks defined for the current project.
+It does not list the scopes the tasks are defined in; use the 'inspect' command for that.
+Tasks produce values.  Use the 'show' command to run the task and print the resulting value.
+"""
+
+	def tasksBrief = "Displays the tasks defined for the current project."
+	def tasksDetailed = TasksCommand + "\n\t" + tasksBrief
+
 	def helpBrief = (HelpCommand + " command*", "Displays this help message or prints detailed help on requested commands.")
 	def helpDetailed = "If an argument is provided, this prints detailed help for that command.\nOtherwise, this prints a help summary."
 

main/KeyIndex.scala

@@ -6,7 +6,7 @@ package sbt
 	import java.net.URI
 	import Project.ScopedKey
 	import complete.DefaultParsers.validID
-	import Types.idFun
+	import Types.{idFun, some}
 
 object KeyIndex
 {
@@ -19,6 +19,7 @@ object KeyIndex
 		def configs(proj: Option[ResolvedReference]) = concat(_.configs(proj))
 		def tasks(proj: Option[ResolvedReference], conf: Option[String]) = concat(_.tasks(proj, conf))
 		def tasks(proj: Option[ResolvedReference], conf: Option[String], key: String) = concat(_.tasks(proj, conf, key))
+		def keys(proj: Option[ResolvedReference]) = concat(_.keys(proj))
 		def keys(proj: Option[ResolvedReference], conf: Option[String]) = concat(_.keys(proj, conf))
 		def keys(proj: Option[ResolvedReference], conf: Option[String], task: Option[AttributeKey[_]]) = concat(_.keys(proj, conf, task))
 		def concat[T](f: KeyIndex => Set[T]): Set[T] =
@@ -40,6 +41,7 @@ trait KeyIndex
 	def configs(proj: Option[ResolvedReference]): Set[String]
 	def tasks(proj: Option[ResolvedReference], conf: Option[String]): Set[AttributeKey[_]]
 	def tasks(proj: Option[ResolvedReference], conf: Option[String], key: String): Set[AttributeKey[_]]
+	def keys(proj: Option[ResolvedReference]): Set[String]
 	def keys(proj: Option[ResolvedReference], conf: Option[String]): Set[String]
 	def keys(proj: Option[ResolvedReference], conf: Option[String], task: Option[AttributeKey[_]]): Set[String]
 }
@@ -84,7 +86,8 @@ private final class KeyIndex0(val data: BuildIndex) extends ExtendableKeyIndex
 	def configs(project: Option[ResolvedReference]): Set[String] = confIndex(project).configs
 	def tasks(proj: Option[ResolvedReference], conf: Option[String]): Set[AttributeKey[_]] = keyIndex(proj, conf).tasks
 	def tasks(proj: Option[ResolvedReference], conf: Option[String], key: String): Set[AttributeKey[_]] = keyIndex(proj, conf).tasks(key)
-	def keys(project: Option[ResolvedReference], conf: Option[String]): Set[String] = keyIndex(project, conf).allKeys
+	def keys(proj: Option[ResolvedReference]): Set[String] = (Set.empty[String] /: optConfigs(proj)) { (s,c) => s ++ keys(proj, c) }
+	def keys(proj: Option[ResolvedReference], conf: Option[String]): Set[String] = keyIndex(proj, conf).allKeys
 	def keys(proj: Option[ResolvedReference], conf: Option[String], task: Option[AttributeKey[_]]): Set[String] = keyIndex(proj, conf).keys(task)
 
 	def keyIndex(proj: Option[ResolvedReference], conf: Option[String]): AKeyIndex =
@@ -101,6 +104,7 @@ private final class KeyIndex0(val data: BuildIndex) extends ExtendableKeyIndex
 			case Some(BuildRef(uri)) => (Some(uri), None)
 			case _ => (None, None)
 		}
+	private[this] def optConfigs(project: Option[ResolvedReference]): Seq[Option[String]] = None +: (configs(project).toSeq map some.fn)
 
 	def add(scoped: ScopedKey[_]): ExtendableKeyIndex =
 		if(validID(scoped.key.label)) add0(scoped) else this

main/Main.scala

@@ -85,7 +85,7 @@ object BuiltinCommands
 	def ConsoleCommands: Seq[Command] = Seq(ignore, exit, IvyConsole.command, act, nop)
 	def ScriptCommands: Seq[Command] = Seq(ignore, exit, Script.command, act, nop)
 	def DefaultCommands: Seq[Command] = Seq(ignore, help, reboot, read, history, continuous, exit, loadProject, loadProjectImpl, loadFailed, Cross.crossBuild, Cross.switchVersion,
-		projects, project, setOnFailure, clearOnFailure, ifLast, multi, shell, set, inspect, eval, alias, append, last, lastGrep, nop, sessionCommand, act)
+		projects, project, setOnFailure, clearOnFailure, ifLast, multi, shell, set, tasks, inspect, eval, alias, append, last, lastGrep, nop, sessionCommand, act)
 	def DefaultBootCommands: Seq[String] = LoadProject :: (IfLast + " " + Shell) :: Nil
 
 	def nop = Command.custom(s => success(() => s))
@@ -108,13 +108,34 @@ object BuiltinCommands
 	{
 		val message =
 			if(args.isEmpty)
-				h.map( _.brief match { case (a,b) => a + " : " + b } ).mkString("\n", "\n", "\n")
+				aligned("  ", "   ", h.map(_.brief)).mkString("\n", "\n", "\n")
 			else
 				h flatMap detail(args) mkString("\n", "\n\n", "\n")
 		System.out.println(message)
 		s
 	}
 
+	def tasks = Command.command(TasksCommand, tasksBrief, tasksDetailed) { s =>
+		System.out.println(tasksPreamble)
+		System.out.println(tasksHelp(s))
+		s
+	}
+	def tasksHelp(s: State): String =
+	{
+		val extracted = Project.extract(s)
+		import extracted._
+		val index = structure.index
+		val pairs = index.keyIndex.keys(Some(currentRef)).toSeq map index.keyMap sortBy(_.label) flatMap taskStrings
+		aligned("  ", "   ", pairs) mkString("\n", "\n", "")
+	}
+	def taskStrings(key: AttributeKey[_]): Option[(String, String)]  =  key.description map { d => (key.label, d) }
+	def aligned(pre: String, sep: String, in: Seq[(String, String)]): Seq[String] =
+	{
+		val width = in.map(_._1.length).max
+		in.map { case (a, b) => ("  " + fill(a, width) + sep + b) }
+	}
+	def fill(s: String, size: Int)  =  s + " " * math.max(size - s.length, 0)
+
 	def alias = Command.make(AliasCommand, AliasBrief, AliasDetailed) { s =>
 		val name = token(OpOrID.examples( aliasNames(s) : _*) )
 		val assign = token(OptSpace ~ '=' ~ OptSpace)