history commands: !!, !?string, !-n, !n, !string

sbt/src/main/scala/sbt/LineReader.scala

@@ -36,6 +36,10 @@ abstract class JLine extends LineReader
 			case null => None
 			case x => Some(x.trim)
 		}
+	def getHistory: Array[String]  =
+		JLine.synchronized {
+			reader.getHistory.getHistoryList.toArray(new Array[String](0))
+		}
 }
 private object JLine
 {
@@ -49,23 +53,33 @@ private object JLine
 		}
 	def createReader() =
 		withTerminal { t =>
-			t.synchronized
-			{
-				val cr = new ConsoleReader
-				t.enableEcho()
-				cr.setBellEnabled(false)
-				cr
-			}
+			val cr = new ConsoleReader
+			t.enableEcho()
+			cr.setBellEnabled(false)
+			cr
 		}
 	def withJLine[T](action: => T): T =
 		withTerminal { t =>
-			t.synchronized
+			t.disableEcho()
+			try { action }
+			finally { t.enableEcho() }
+		}
+	private[sbt] def initializeHistory(cr: ConsoleReader, historyPath: Option[Path], log: Logger): Unit =
+		for(historyLocation <- historyPath)
+		{
+			val historyFile = historyLocation.asFile
+			Control.trapAndLog(log)
 			{
-				t.disableEcho()
-				try { action }
-				finally { t.enableEcho() }
+				historyFile.getParentFile.mkdirs()
+				cr.getHistory.setHistoryFile(historyFile)
 			}
 		}
+	def simple(historyPath: Option[Path], log: Logger): SimpleReader = new SimpleReader(historyPath, log)
+}
+class SimpleReader private[sbt] (historyPath: Option[Path], log: Logger) extends JLine
+{
+	protected[this] val reader = JLine.createReader()
+	JLine.initializeHistory(reader, historyPath, log)
 }
 object SimpleReader extends JLine
 {
@@ -77,15 +91,7 @@ private[sbt] final class LazyJLineReader(historyPath: Option[Path], completor: =
 	{
 		val cr = new ConsoleReader
 		cr.setBellEnabled(false)
-		for(historyLocation <- historyPath)
-		{
-			val historyFile = historyLocation.asFile
-			Control.trapAndLog(log)
-			{
-				historyFile.getParentFile.mkdirs()
-				cr.getHistory.setHistoryFile(historyFile)
-			}
-		}
+		JLine.initializeHistory(cr, historyPath, log)
 		cr.addCompletor(new LazyCompletor(completor))
 		cr
 	}

sbt/src/main/scala/sbt/Main.scala

@@ -197,6 +197,15 @@ class xMain extends xsbti.AppMain
 						case Some(newProject) => continue(newProject, tail, failAction)
 						case None => failed(BuildErrorExitCode)
 					}
+
+				case action :: tail if action.startsWith(HistoryPrefix) =>
+					historyCommand(action.substring(HistoryPrefix.length).trim, baseProject.historyPath, project.log) match
+					{
+						case Some(command) =>
+							println(command)  //better to print it than to log it
+							continue(project, command :: tail, failAction)
+						case None => failed(UsageErrorExitCode)
+					}
 					
 				case action :: tail if action.startsWith(FileCommandsPrefix) =>
 					getSource(action.substring(FileCommandsPrefix.length).trim, baseProject.info.projectDirectory) match
@@ -271,6 +280,37 @@ class xMain extends xsbti.AppMain
 			if(message eq null) None else Some(message)
 		}
 	}
+	private def historyCommand(s: String, historyPath: Option[Path], log: Logger): Option[String] =
+	{
+		val lines = historyPath.toList.flatMap(h => xsbt.FileUtilities.readLines(h.asFile) ).toArray
+		if(lines.isEmpty)
+		{
+			log.warn("No history")
+			None
+		}
+		else
+		{
+			def replaceLastCommand(s: String) {
+				lines(lines.length - 1) = s
+				historyPath foreach { h => xsbt.FileUtilities.writeLines(h.asFile, lines) }
+			}
+			val command = historyCommand(complete.History(lines, log), s, log)
+			command.foreach(replaceLastCommand)
+			command
+		}
+	}
+	private def historyCommand(history: complete.History, s: String, log: Logger): Option[String] =
+	{
+		val ContainsPrefix = "?"
+		val Last = "!"
+		val PreviousPrefix = "-"
+		if(s == Last)
+			history !!
+		else if(s.startsWith(ContainsPrefix))
+			history !? s.substring(ContainsPrefix.length)
+		else
+			history ! s
+	}
 	object SetProject
 	{
 		def unapply(s: String) =
@@ -355,6 +395,7 @@ class xMain extends xsbti.AppMain
 		reader.readLine("> ").getOrElse(ExitCommand)
 	}
 
+	val HistoryPrefix = "!"
 	/** The name of the command that loads a console with access to the current project through the variable 'project'.*/
 	val ProjectConsoleAction = "console-project"
 	/** The name of the command that shows the current project and logging level of that project.*/
@@ -398,7 +439,7 @@ class xMain extends xsbti.AppMain
 	/** The prefix used to identify a file or local port to read commands from. */
 	val FileCommandsPrefix = "<"
 	/** The prefix used to identify the action to run after an error*/
-	val FailureHandlerPrefix = "!"
+	val FailureHandlerPrefix = "-"
 	/** The prefix used to identify commands for managing processors.*/
 	val ProcessorPrefix = "*"
 

sbt/src/main/scala/sbt/complete/History.scala

@@ -0,0 +1,42 @@
+package sbt.complete
+
+import History.number
+
+final class History private(lines: Array[String], log: Logger) extends NotNull
+{
+	private def reversed = lines.reverse
+
+	def all: Seq[String] = lines.toArray
+	def size = lines.length
+	def !! : Option[String] = !- (1)
+	def apply(i: Int): Option[String] = if(0 <= i && i < size) Some( lines(i) ) else { log.error("Invalid history index: " + i); None }
+	def !(i: Int): Option[String] = apply(i)
+
+	def !(s: String): Option[String] =
+		number(s) match
+		{
+			case Some(n) => if(n < 0) !- (-n) else apply(n)
+			case None => nonEmpty(s) { reversed.find(_.startsWith(s)) }
+		}
+	def !- (n: Int): Option[String] = apply(size - n - 1)
+
+	def !?(s: String): Option[String] = nonEmpty(s) { reversed.drop(1).find(_.contains(s)) }
+
+	private def nonEmpty[T](s: String)(act: => Option[T]): Option[T] =
+		if(s.isEmpty)
+		{
+			log.error("No action specified to history command")
+			None
+		}
+		else
+			act
+}
+
+object History
+{
+	def apply(lines: Seq[String], log: Logger): History = new History(lines.toArray, log)
+
+	private def number(s: String): Option[Int] =
+		try { Some(s.toInt) }
+		catch { case e: NumberFormatException => None }
+}