SI-8922 REPL load -v

Verbose mode causes the familiar prompt and
line echo so you can see what you just loaded.

The quit message is pushed up a level in the
process loop.

This has the huge payoff that if you start the
repl and immediately hit ctl-D, you don't have to
wait for the compiler to init (yawn) before you
get a shell prompt back.

1 files changed, 22 insertions, 7 deletions

diff --git a/src/repl/scala/tools/nsc/interpreter/SimpleReader.scala b/src/repl/scala/tools/nsc/interpreter/SimpleReader.scala
index 6634dc6944..49b8433a8c 100644
--- a/src/repl/scala/tools/nsc/interpreter/SimpleReader.scala
+++ b/src/repl/scala/tools/nsc/interpreter/SimpleReader.scala
@@ -22,14 +22,19 @@ extends InteractiveReader
 
   def reset() = ()
   def redrawLine() = ()
-  def readOneLine(prompt: String): String = {
-    if (interactive) {
-      out.print(prompt)
-      out.flush()
-    }
-    in.readLine()
+
+  // InteractiveReader internals
+  protected def readOneLine(prompt: String): String = {
+    echo(prompt)
+    readOneLine()
+  }
+  protected def readOneKey(prompt: String) = sys.error("No char-based input in SimpleReader")
+
+  protected def readOneLine(): String = in.readLine()
+  protected def echo(s: String): Unit = if (interactive) {
+    out.print(s)
+    out.flush()
   }
-  def readOneKey(prompt: String)  = sys.error("No char-based input in SimpleReader")
 }
 
 object SimpleReader {
@@ -39,3 +44,13 @@ object SimpleReader {
   def apply(in: BufferedReader = defaultIn, out: JPrintWriter = defaultOut, interactive: Boolean = true): SimpleReader =
     new SimpleReader(in, out, interactive)
 }
+
+// pretend we are a console for verbose purposes
+trait EchoReader extends SimpleReader {
+  // if there is more input, then maybe echo the prompt and the input
+  override def readOneLine(prompt: String) = {
+    val input = readOneLine()
+    if (input != null) echo(f"$prompt$input%n")
+    input
+  }
+}