Bash completion! The file is automatically crea...

Bash completion! The file is automatically created as part of the build
process and placed in $pack/etc.

% scala -Xprint
-Xprint-icode  -Xprint-pos    -Xprint-types  -Xprint:

% scala -Xprint:
all             flatten         mixin           tailcalls
cleanup         icode           namer           terminal
closelim        inliner         packageobjects  typer
constructors    jvm             parser          uncurry
dce             lambdalift      pickler
erasure         lazyvals        refchecks
explicitouter   liftcode        superaccessors

% scala -g:
line         none         notailcalls  source       vars

% scala -Ystruct-dispatch:
invoke-dynamic  mono-cache      no-cache        poly-cache

Review by community.

2 files changed, 139 insertions, 4 deletions

diff --git a/src/compiler/scala/tools/nsc/Global.scala b/src/compiler/scala/tools/nsc/Global.scala
index 0590797e53..4e14ec6fb1 100644
--- a/src/compiler/scala/tools/nsc/Global.scala
+++ b/src/compiler/scala/tools/nsc/Global.scala
@@ -549,13 +549,16 @@ class Global(var settings: Settings, var reporter: Reporter) extends SymbolTable
   /* The set of phase objects that is the basis for the compiler phase chain */
   protected val phasesSet : HashSet[SubComponent] = new HashSet[SubComponent]
 
-  /** A description of the phases that will run */
-  def phaseDescriptions: String = {
+  /** The names of the phases. */
+  lazy val phaseNames = {
     new Run // force some initialization
-
-    phaseDescriptors map (_.phaseName) mkString "\n" // todo: + " - " + phase.description
+    phaseDescriptors map (_.phaseName)
   }
 
+  /** A description of the phases that will run */
+  def phaseDescriptions: String =
+    phaseNames mkString "\n" // todo: + " - " + phase.description
+
   // ----------- Runs ---------------------------------------
 
   private var curRun: Run = null
diff --git a/src/compiler/scala/tools/util/BashCompletion.scala b/src/compiler/scala/tools/util/BashCompletion.scala
new file mode 100644
index 0000000000..bb36326b7e
--- /dev/null
+++ b/src/compiler/scala/tools/util/BashCompletion.scala
@@ -0,0 +1,132 @@
+/* NSC -- new Scala compiler
+ * Copyright 2006-2010 LAMP/EPFL
+ * @author  Paul Phillips
+ */
+
+package scala.tools
+package util
+
+import nsc.{ Global, Settings }
+import Settings._
+
+/** Examines Settings and generates a bash completion file
+ *  containing both bells and whistles.
+ */
+object BashCompletion {
+  val completionTemplate = """
+# Bash Scala completion
+#
+# Add this file to /etc/bash_completion.d/ (or your local equivalent)
+# or place a line like this in your .bashrc or .profile:
+#
+#   .  /path/to/file/scala_completion.sh
+#
+# For more information, see:
+#
+#   http://bash-completion.alioth.debian.org/
+#
+# This file is generated by running scala.tools.util.BashCompletion.
+#
+
+SCALA_PHASES="@@PHASES@@"
+SCALA_PHASE_SETTINGS=( @@PHASE_SETTINGS@@ )
+SCALA_OPTIONS="@@OPTIONS@@"
+SCALA_OPTIONS_EXPANDED="@@OPTIONS_EXPANDED@@"
+
+_scala_completion()
+{
+  local cur prev opts colonprefixes
+
+  COMPREPLY=()
+  opts=""
+  cur="${COMP_WORDS[COMP_CWORD]}"
+  prev="${COMP_WORDS[COMP_CWORD-1]}"
+  colonprefixes=${cur%"${cur##*:}"}
+
+  # special case escaping madness because bash treats : as a separator.
+  case "${cur}" in
+    -*:*)
+      precolon=$(echo "${cur}" | sed 's/:.*//g')
+
+      for p in ${SCALA_PHASE_SETTINGS[@]}; do
+        if [[ "${precolon}" == "${p}" ]] ; then
+          cur=$(echo "${cur}" | sed 's/.*://g')  # cut cur down to postcolon part
+          opts=${SCALA_PHASES}
+    	  fi
+    	done
+
+    	if [ "${opts}" == "" ] ; then
+    	  opts=${SCALA_OPTIONS_EXPANDED}
+    	fi
+    	;;
+  esac
+
+  if [ "${opts}" == "" ] ; then
+	  opts=${SCALA_OPTIONS}
+  fi
+
+  COMPREPLY=( $(compgen -W "${opts}" -- ${cur}) )
+
+  local i=${#COMPREPLY[*]}
+  while [ $((--i)) -ge 0 ]; do
+    COMPREPLY[$i]=${COMPREPLY[$i]#"$colonprefixes"}
+  done
+
+  return 0
+}
+
+_scala_commands()
+{
+@@PROGRAMS@@
+}
+_scala_commands
+  """.trim
+
+  private lazy val settings = new Settings()
+
+  val phaseNames = "all" :: (new Global(settings) phaseNames)
+  val phaseSettings = settings.visibleSettings partialMap { case x: PhasesSetting => "\"" + x.name + "\"" }
+
+  def settingStrings(s: Setting, expanded: Boolean) = s match {
+    case x: ChoiceSetting       => if (expanded) x.choices map (x.name + ":" + _) else List(x.name + ":")
+    case x: PhasesSetting       => List(x.name + ":")
+    case x                      => List(x.name)
+  }
+
+  /** We embed one list which stops at : and another where all choice settings are expanded out
+   *  to include the choices.
+   */
+  def settingNames = settings.visibleSettings.toList flatMap (x => settingStrings(x, false)) sorted
+  def settingNamesExpanded = settings.visibleSettings.toList flatMap (x => settingStrings(x, true)) sorted
+
+  def commandForName(name: String) = "  complete -o default -F _scala_completion " + name + "\n"
+  def interpolate(template: String, what: (String, String)*) =
+    what.foldLeft(template) {
+      case (text, (key, value)) =>
+        val token = "@@" + key + "@@"
+
+        (text indexOf token) match {
+          case -1   => error("Token '%s' does not exist." format token)
+          case idx  => (text take idx) + value + (text drop idx drop token.length)
+        }
+    }
+
+  def create(cmds: List[String]) = {
+    interpolate(completionTemplate,
+      "PROGRAMS"          -> (cmds map commandForName mkString ""),
+      "OPTIONS"           -> (settingNames mkString " "),
+      "OPTIONS_EXPANDED"  -> (settingNamesExpanded mkString " "),
+      "PHASES"            -> (phaseNames mkString " "),
+      "PHASE_SETTINGS"    -> (phaseSettings mkString " ")
+    )
+  }
+
+  def main(args: Array[String]): Unit = {
+    val commands = if (args.isEmpty) List("fsc", "scala", "scalac", "scaladoc") else args.toList
+    val result = create(commands)
+    if (result contains "@@")
+      error("Some tokens were not replaced: text is " + result)
+
+    println(result)
+  }
+}
\ No newline at end of file