Fix for SI-4945, repl hang on -i input.

Other breakage had accumulated among Settings. I determined
that once upon a time, "MultiStringSetting" accepted arguments
like this:

  scala -foo bip bop bar

Somewhere this was changed to force a : argument, like

  scala -foo:bip,bop,bar

This incurs breakage.  The repl has always advertised its -i
option without a colon and it has always been a MultiStringSetting.
Forcing everything into the : seemed like the wrong thing,
especially because it will stomp on any whitespace containing
arguments, whereas in the original form

  scala -foo bip "bop bar" baz

will yield its arguments as given.

So lacking any good ideas and knowing something probably depends
on each way already, I made it work both ways.

5 files changed, 37 insertions, 23 deletions

diff --git a/src/compiler/scala/reflect/macros/runtime/Settings.scala b/src/compiler/scala/reflect/macros/runtime/Settings.scala
index b7dba665fa..9c24273cd7 100644
--- a/src/compiler/scala/reflect/macros/runtime/Settings.scala
+++ b/src/compiler/scala/reflect/macros/runtime/Settings.scala
@@ -5,9 +5,9 @@ trait Settings {
   self: Context =>
 
   def settings: List[String] = {
-    val optionName = universe.settings.XmacroSettings.name
-    val settings = compilerSettings.find(opt => opt.startsWith(optionName)).map(opt => opt.substring(optionName.length + 1)).getOrElse("")
-    settings.split(",").toList
+    val us = universe.settings
+    import us._
+    userSetSettings collectFirst { case x: MultiStringSetting if x.name == XmacroSettings.name => x.value } getOrElse Nil
   }
 
   def compilerSettings: List[String] = universe.settings.recreateArgs
@@ -33,4 +33,4 @@ trait Settings {
     try op
     finally setCompilerSettings(old)
   }
-}
\ No newline at end of file
+}
diff --git a/src/compiler/scala/tools/nsc/MainGenericRunner.scala b/src/compiler/scala/tools/nsc/MainGenericRunner.scala
index cc1139f8a7..f1c3e80b83 100644
--- a/src/compiler/scala/tools/nsc/MainGenericRunner.scala
+++ b/src/compiler/scala/tools/nsc/MainGenericRunner.scala
@@ -58,6 +58,10 @@ class MainGenericRunner {
     def isI   = !settings.loadfiles.isDefault
     def dashi = settings.loadfiles.value
 
+    // Deadlocks on startup under -i unless we disable async.
+    if (isI)
+      settings.Yreplsync.value = true
+
     def combinedCode  = {
       val files   = if (isI) dashi map (file => File(file).slurp()) else Nil
       val str     = if (isE) List(dashe) else Nil
diff --git a/src/compiler/scala/tools/nsc/settings/MutableSettings.scala b/src/compiler/scala/tools/nsc/settings/MutableSettings.scala
index fc833e2c26..7f627f7904 100644
--- a/src/compiler/scala/tools/nsc/settings/MutableSettings.scala
+++ b/src/compiler/scala/tools/nsc/settings/MutableSettings.scala
@@ -68,7 +68,7 @@ class MutableSettings(val errorFn: String => Unit)
         if (isOpt) {
           val newArgs = parseParams(args)
           if (args eq newArgs) {
-            errorFn("bad option: '" + x + "'")
+            errorFn(s"bad option: '$x'")
             (false, args)
           }
           // discard empties, sometimes they appear because of ant or etc.
@@ -536,7 +536,7 @@ class MutableSettings(val errorFn: String => Unit)
     }
     override def tryToSetColon(args: List[String]) = tryToSet(args)
     override def tryToSetFromPropertyValue(s: String) = tryToSet(s.trim.split(',').toList)
-    def unparse: List[String] = value map { name + ":" + _ }
+    def unparse: List[String] = name :: value
 
     withHelpSyntax(name + ":<" + arg + ">")
   }
diff --git a/src/reflect/scala/reflect/internal/settings/MutableSettings.scala b/src/reflect/scala/reflect/internal/settings/MutableSettings.scala
index e9899f690d..96fd50646f 100644
--- a/src/reflect/scala/reflect/internal/settings/MutableSettings.scala
+++ b/src/reflect/scala/reflect/internal/settings/MutableSettings.scala
@@ -14,6 +14,7 @@ abstract class MutableSettings extends AbsSettings {
   type Setting <: SettingValue
   type BooleanSetting <: Setting { type T = Boolean }
   type IntSetting <: Setting { type T = Int }
+  type MultiStringSetting <: Setting { type T = List[String] }
 
   // basically this is a value which remembers if it's been modified
   trait SettingValue extends AbsSettingValue {
@@ -46,4 +47,4 @@ abstract class MutableSettings extends AbsSettings {
   def XoldPatmat: BooleanSetting
   def XnoPatmatAnalysis: BooleanSetting
   def XfullLubs: BooleanSetting
-}
\ No newline at end of file
+}
diff --git a/src/reflect/scala/reflect/runtime/Settings.scala b/src/reflect/scala/reflect/runtime/Settings.scala
index eedb88320b..da4f4fbda1 100644
--- a/src/reflect/scala/reflect/runtime/Settings.scala
+++ b/src/reflect/scala/reflect/runtime/Settings.scala
@@ -1,11 +1,13 @@
 package scala.reflect
 package runtime
 
+import scala.reflect.internal.settings.MutableSettings
+
 /** The Settings class for runtime reflection.
  *  This should be refined, so that settings are settable via command
  *  line options or properties.
  */
-class Settings extends internal.settings.MutableSettings {
+class Settings extends MutableSettings {
 
   trait Setting extends SettingValue { }
 
@@ -21,20 +23,27 @@ class Settings extends internal.settings.MutableSettings {
     override def value: Int = v
   }
 
-  val overrideObjects = new BooleanSetting(false)
-  val debug = new BooleanSetting(false)
-  val Ynotnull = new BooleanSetting(false)
-  val explaintypes = new BooleanSetting(false)
-  val verbose = new BooleanSetting(false)
-  val uniqid = new BooleanSetting(false)
-  val Yshowsymkinds = new BooleanSetting(false)
-  val Xprintpos = new BooleanSetting(false)
-  val printtypes = new BooleanSetting(false)
-  val Yrecursion = new IntSetting(0)
-  val maxClassfileName = new IntSetting(255)
-  val Xexperimental = new BooleanSetting(false)
-  val deepCloning = new BooleanSetting (false)
-  val XoldPatmat = new BooleanSetting(false)
+  class MultiStringSetting(xs: List[String]) extends Setting {
+    type T = List[String]
+    protected var v: List[String] = xs
+    override def value: List[String] = v
+  }
+
+  val Xexperimental     = new BooleanSetting(false)
+  val XfullLubs         = new BooleanSetting(false)
   val XnoPatmatAnalysis = new BooleanSetting(false)
-  val XfullLubs = new BooleanSetting(false)
+  val XoldPatmat        = new BooleanSetting(false)
+  val Xprintpos         = new BooleanSetting(false)
+  val Ynotnull          = new BooleanSetting(false)
+  val Yshowsymkinds     = new BooleanSetting(false)
+  val debug             = new BooleanSetting(false)
+  val deepCloning       = new BooleanSetting(false)
+  val explaintypes      = new BooleanSetting(false)
+  val overrideObjects   = new BooleanSetting(false)
+  val printtypes        = new BooleanSetting(false)
+  val uniqid            = new BooleanSetting(false)
+  val verbose           = new BooleanSetting(false)
+
+  val Yrecursion        = new IntSetting(0)
+  val maxClassfileName  = new IntSetting(255)
 }