Fix for #296

The handling of informative messages in CompileServer and in Main was
duplicated, and the two copies slowly diverged over time. The code has
now been refactored, cleaned up, and made more general.

The FakePos(fsc) message was due to a missing override def toString.

Both problems are fixed.

1 files changed, 30 insertions, 0 deletions

diff --git a/src/compiler/scala/tools/nsc/CompilerCommand.scala b/src/compiler/scala/tools/nsc/CompilerCommand.scala
index 9ad0bb2539..6f22fb8612 100644
--- a/src/compiler/scala/tools/nsc/CompilerCommand.scala
+++ b/src/compiler/scala/tools/nsc/CompilerCommand.scala
@@ -66,6 +66,36 @@ class CompilerCommand(arguments: List[String], val settings: Settings,
                 "\n")
   }
 
+  // If any of these settings is set, the compiler shouldn't
+  // start; an informative message of some sort
+  // should be printed instead.
+  // (note: do not add "files.isEmpty" do this list)
+  val stopSettings=List[(()=>Boolean,
+                         (Global)=>String)](
+    (()=> settings.help.value, compiler =>
+      usageMsg + compiler.pluginOptionsHelp
+    ),
+    (()=> settings.Xhelp.value, compiler =>
+      xusageMsg
+    ),
+    (()=> settings.Yhelp.value, compiler =>
+      yusageMsg
+    ),
+    (()=> settings.showPlugins.value, compiler =>
+      compiler.pluginDescriptions
+    ),
+    (()=> settings.showPhases.value, compiler =>
+      compiler.phaseDescriptions
+    )
+  )
+
+  def shouldStopWithInfo = stopSettings.exists({pair => (pair._1)()})
+  def getInfoMessage(compiler:Global) =
+    stopSettings.find({pair => (pair._1)()}) match {
+      case Some((test,getMessage)) => getMessage(compiler)
+      case None => ""
+    }
+
 
   /** Whether the command was processed okay */
   var ok = true