Merge pull request #1406 from dotty-staging/fix-output-diff

Make -Xprint-diff an opt-in option.

Author: odersky

src/dotty/tools/dotc/Run.scala

@@ -92,8 +92,10 @@ class Run(comp: Compiler)(implicit ctx: Context) {
 
     last match {
       case SomePrintedTree(phase, lastTreeSting) if lastTreeSting != treeString =>
-        val diff = DiffUtil.mkColoredCodeDiff(treeString, lastTreeSting, ctx.settings.XprintDiffDel.value)
-        ctx.echo(diff)
+        val msg =
+          if (!ctx.settings.XprintDiff.value && !ctx.settings.XprintDiffDel.value) treeString
+          else DiffUtil.mkColoredCodeDiff(treeString, lastTreeSting, ctx.settings.XprintDiffDel.value)
+        ctx.echo(msg)
         SomePrintedTree(squashedPhase.toString, treeString)
 
       case SomePrintedTree(phase, lastTreeSting) =>

src/dotty/tools/dotc/config/ScalaSettings.scala

@@ -85,7 +85,8 @@ class ScalaSettings extends Settings.SettingGroup {
   val writeICode = PhasesSetting("-Xprint-icode", "Log internal icode to *.icode files after", "icode")
   val Xprintpos = BooleanSetting("-Xprint-pos", "Print tree positions, as offsets.")
   val printtypes = BooleanSetting("-Xprint-types", "Print tree types (debugging option).")
-  val XprintDiffDel = BooleanSetting("-Xprint-diff-del", "Print deleted parts of the tree since last print.")
+  val XprintDiff = BooleanSetting("-Xprint-diff", "Print changed parts of the tree since last print.")
+  val XprintDiffDel = BooleanSetting("-Xprint-diff-del", "Print chaged parts of the tree since last print including deleted parts.")
   val prompt = BooleanSetting("-Xprompt", "Display a prompt after each error (debugging option).")
   val script = StringSetting("-Xscript", "object", "Treat the source file as a script and wrap it in a main method.", "")
   val mainClass = StringSetting("-Xmain-class", "path", "Class for manifest's Main-Class entry (only useful with -d <jar>)", "")