repl: Ignore spurious arguments in :settings

Author: dwijnand

compiler/src/dotty/tools/repl/ReplDriver.scala

@@ -8,6 +8,7 @@ import dotty.tools.dotc.ast.{tpd, untpd}
 import dotty.tools.dotc.config.CommandLineParser.tokenize
 import dotty.tools.dotc.config.Properties.{javaVersion, javaVmName, simpleVersionString}
 import dotty.tools.dotc.core.Contexts._
+import dotty.tools.dotc.core.Decorators._
 import dotty.tools.dotc.core.Phases.{unfusedPhases, typerPhase}
 import dotty.tools.dotc.core.Denotations.Denotation
 import dotty.tools.dotc.core.Flags._
@@ -424,8 +425,11 @@ class ReplDriver(settings: Array[String],
       case _  =>
         setup(tokenize(arg).toArray, rootCtx) match
           case Some((files, ictx)) =>
-            ictx.base.initialize()(using ictx)
-            rootCtx = ictx
+            inContext(ictx) {
+              if files.nonEmpty then out.println(i"Ignoring spurious arguments: $files%, %")
+              ictx.base.initialize()(using ictx)
+              rootCtx = ictx
+            }
           case _ =>
         state.copy(context = rootCtx)
 

compiler/test-resources/repl/settings-command

@@ -2,7 +2,8 @@ scala> def f(thread: Thread) = thread.stop()
 there were 1 deprecation warning(s); re-run with -deprecation for details
 def f(thread: Thread): Unit
 
-scala>:settings -deprecation
+scala>:settings -deprecation foo.scala
+Ignoring spurious arguments: foo.scala
 
 scala> def f(thread: Thread) = thread.stop()
 1 warning found