SI-9206: REPL custom welcome message

Can be specified by `-Dscala.repl.welcome=Greeting` or in properties
file. It takes the same format arguments as the prompt, viz, version,
Java version and JVM name.

It can be disabled by `-Dscala.repl.welcome` with no text.

1 files changed, 9 insertions, 0 deletions

diff --git a/src/compiler/scala/tools/nsc/Properties.scala b/src/compiler/scala/tools/nsc/Properties.scala
index ca7d8776d4..c8b9922623 100644
--- a/src/compiler/scala/tools/nsc/Properties.scala
+++ b/src/compiler/scala/tools/nsc/Properties.scala
@@ -12,8 +12,17 @@ object Properties extends scala.util.PropertiesTrait {
   protected def pickJarBasedOn = classOf[Global]
 
   // settings based on jar properties, falling back to System prefixed by "scala."
+
+  // messages to display at startup or prompt, format string with string parameters
+  // Scala version, Java version, JVM name
   def residentPromptString = scalaPropOrElse("resident.prompt", "\nnsc> ")
   def shellPromptString    = scalaPropOrElse("shell.prompt", "%nscala> ")
+  def shellWelcomeString   = scalaPropOrElse("shell.welcome",
+    """Welcome to Scala %1$s (%3$s, Java %2$s).
+      |Type in expressions to have them evaluated.
+      |Type :help for more information.""".stripMargin
+  )
+
   // message to display at EOF (which by default ends with
   // a newline so as not to break the user's terminal)
   def shellInterruptedString = scalaPropOrElse("shell.interrupted", f":quit$lineSeparator")