Initial implementation featuring two different highlighters

One was implemted by hand and the other by using dotty's parser. The one
built by hand is shorter, and behaves correctly.

The scanner one is unfortunately not ready for testing - there are too
many things that are workarounds for it to be a good solution as of now

The code added from Ammonite is licensed under MIT, not sure where to
put the license - but will add it once I know.

1 files changed, 71 insertions, 0 deletions

diff --git a/src/dotty/tools/dotc/repl/AmmoniteReader.scala b/src/dotty/tools/dotc/repl/AmmoniteReader.scala
new file mode 100644
index 000000000..0c4dd80ee
--- /dev/null
+++ b/src/dotty/tools/dotc/repl/AmmoniteReader.scala
@@ -0,0 +1,71 @@
+package dotty.tools
+package dotc
+package repl
+
+import core.Contexts._
+import ammonite.terminal._
+import LazyList._
+import Ansi.Color
+import filters._
+import BasicFilters._
+import GUILikeFilters._
+import util.SourceFile
+
+class AmmoniteReader extends InteractiveReader {
+  val interactive = true
+
+  val reader = new java.io.InputStreamReader(System.in)
+  val writer = new java.io.OutputStreamWriter(System.out)
+  val cutPasteFilter = ReadlineFilters.CutPasteFilter()
+  var history = List.empty[String]
+  val selectionFilter = GUILikeFilters.SelectionFilter(indent = 2)
+  val multilineFilter: Filter = Filter("multilineFilter") {
+    case TermState(lb ~: rest, b, c, _)
+      if (lb == 10 || lb == 13) => // Enter
+
+      BasicFilters.injectNewLine(b, c, rest)
+  }
+  def readLine(prompt: String)(implicit ctx: Context): String = {
+    val historyFilter = new HistoryFilter(
+      () => history.toVector,
+      Console.BLUE,
+      AnsiNav.resetForegroundColor
+    )
+
+    val allFilters = Filter.merge(
+      UndoFilter(),
+      historyFilter,
+      selectionFilter,
+      GUILikeFilters.altFilter,
+      GUILikeFilters.fnFilter,
+      ReadlineFilters.navFilter,
+      //autocompleteFilter,
+      cutPasteFilter,
+      //multilineFilter,
+      BasicFilters.all
+    )
+
+    Terminal.readLine(
+      Console.BLUE + prompt + Console.RESET,
+      reader,
+      writer,
+      allFilters,
+      displayTransform = (buffer, cursor) => {
+        val ansiBuffer = Ansi.Str.parse(SyntaxHighlighting(buffer))
+        //val ansiBuffer = Ansi.Str.parse(SyntaxHighlighting(new SourceFile("<console>", buffer)))
+        val (newBuffer, cursorOffset) = SelectionFilter.mangleBuffer(
+          selectionFilter, ansiBuffer, cursor, Ansi.Reversed.On
+        )
+        val newNewBuffer = HistoryFilter.mangleBuffer(
+          historyFilter, newBuffer, cursor,
+          Ansi.Color.Green
+        )
+
+        (newNewBuffer, cursorOffset)
+      }
+    ) match {
+      case Some(s) => history = s :: history; s
+      case None => ":q"
+    }
+  }
+}