feat: update bridge to account for actions

compiler/src/dotty/tools/dotc/reporting/CodeAction.scala

@@ -0,0 +1,9 @@
+package dotty.tools.dotc.reporting
+
+import dotty.tools.dotc.rewrites.Rewrites.ActionPatch
+
+case class CodeAction(
+  title: String,
+  description: java.util.Optional[String],
+  patches: java.util.List[ActionPatch]
+)

compiler/src/dotty/tools/dotc/reporting/Message.scala

@@ -10,7 +10,6 @@ import printing.Formatting.hl
 import config.SourceVersion
 
 import scala.language.unsafeNulls
-
 import scala.annotation.threadUnsafe
 
 /** ## Tips for error message generation
@@ -415,6 +414,9 @@ abstract class Message(val errorId: ErrorMessageID)(using Context) { self =>
    */
   def showAlways = false
 
+  def actions(using Context): java.util.List[CodeAction] =
+    java.util.Collections.emptyList
+
   override def toString = msg
 }
 

compiler/src/dotty/tools/dotc/reporting/messages.scala

@@ -29,6 +29,9 @@ import transform.SymUtils._
 import scala.util.matching.Regex
 import java.util.regex.Matcher.quoteReplacement
 import cc.CaptureSet.IdentityCaptRefMap
+import dotty.tools.dotc.rewrites.Rewrites.ActionPatch
+import dotty.tools.dotc.util.Spans.Span
+import dotty.tools.dotc.util.SourcePosition
 
 /**  Messages
   *  ========
@@ -1846,12 +1849,26 @@ class FailureToEliminateExistential(tp: Type, tp1: Type, tp2: Type, boundSyms: L
         |are only approximated in a best-effort way."""
 }
 
-class OnlyFunctionsCanBeFollowedByUnderscore(tp: Type)(using Context)
+class OnlyFunctionsCanBeFollowedByUnderscore(tp: Type, tree: untpd.PostfixOp)(using Context)
   extends SyntaxMsg(OnlyFunctionsCanBeFollowedByUnderscoreID) {
   def msg(using Context) = i"Only function types can be followed by ${hl("_")} but the current expression has type $tp"
   def explain(using Context) =
     i"""The syntax ${hl("x _")} is no longer supported if ${hl("x")} is not a function.
         |To convert to a function value, you need to explicitly write ${hl("() => x")}"""
+
+  override def actions(using Context) =
+    val untpd.PostfixOp(qual, Ident(nme.WILDCARD)) = tree: @unchecked
+    import scala.language.unsafeNulls
+    import scala.jdk.CollectionConverters.*
+    List(
+      CodeAction(title = "Rewrite to function value",
+        description =  java.util.Optional.empty(),
+        patches = List(
+          ActionPatch(SourcePosition(tree.source, Span(tree.span.start)), "(() => "),
+          ActionPatch(SourcePosition(tree.source, Span(qual.span.end, tree.span.end)), ")")
+        ).asJava
+      )
+    ).asJava
 }
 
 class MissingEmptyArgumentList(method: String)(using Context)

compiler/src/dotty/tools/dotc/rewrites/Rewrites.scala

@@ -7,6 +7,7 @@ import core.Contexts._
 import collection.mutable
 import scala.annotation.tailrec
 import dotty.tools.dotc.reporting.Reporter
+import dotty.tools.dotc.util.SourcePosition;
 
 import java.io.OutputStreamWriter
 import java.nio.charset.StandardCharsets.UTF_8
@@ -19,6 +20,8 @@ object Rewrites {
     def delta = replacement.length - (span.end - span.start)
   }
 
+  case class ActionPatch(srcPos: SourcePosition, replacement: String)
+
   private class Patches(source: SourceFile) {
     private[Rewrites] val pbuf = new mutable.ListBuffer[Patch]()
 

compiler/src/dotty/tools/dotc/typer/Typer.scala

@@ -2941,7 +2941,9 @@ class Typer(@constructorOnly nestingLevel: Int = 0) extends Namer
       case closure(_, _, _) =>
       case _ =>
         val recovered = typed(qual)(using ctx.fresh.setExploreTyperState())
-        report.errorOrMigrationWarning(OnlyFunctionsCanBeFollowedByUnderscore(recovered.tpe.widen), tree.srcPos, from = `3.0`)
+        report.errorOrMigrationWarning(
+          OnlyFunctionsCanBeFollowedByUnderscore(recovered.tpe.widen, tree), tree.srcPos, from = `3.0`
+        )
         if (migrateTo3) {
           // Under -rewrite, patch `x _` to `(() => x)`
           patch(Span(tree.span.start), "(() => ")

project/Dependencies.scala

@@ -28,6 +28,6 @@ object Dependencies {
     "com.vladsch.flexmark" % "flexmark-ext-yaml-front-matter" % flexmarkVersion,
   )
 
-  val newCompilerInterface = "org.scala-sbt" % "compiler-interface" % "1.8.0"
+  val newCompilerInterface = "org.scala-sbt" % "compiler-interface" % "1.9.0-RC3"
   val oldCompilerInterface = "org.scala-sbt" % "compiler-interface" % "1.3.5"
 }

sbt-bridge/src/dotty/tools/xsbt/Action.java

@@ -0,0 +1,28 @@
+package dotty.tools.xsbt;
+
+import java.util.Optional;
+
+final public class Action implements xsbti.Action {
+  private final String _title;
+  private final Optional<String> _description;
+  private final WorkspaceEdit _edit;
+
+  public Action(String title, Optional<String> description, WorkspaceEdit edit) {
+    super();
+    this._title = title;
+    this._description = description;
+    this._edit = edit;
+  }
+
+  public String title() {
+    return _title;
+  }
+
+  public Optional<String> description() {
+    return _description;
+  }
+
+  public WorkspaceEdit edit() {
+    return _edit;
+  }
+}

sbt-bridge/src/dotty/tools/xsbt/DelegatingReporter.java

@@ -3,11 +3,14 @@
  */
 package dotty.tools.xsbt;
 
+import java.util.List;
+
 import scala.Tuple2;
 import scala.collection.mutable.HashMap;
 
 import dotty.tools.dotc.core.Contexts.Context;
 import dotty.tools.dotc.reporting.AbstractReporter;
+import dotty.tools.dotc.reporting.CodeAction;
 import dotty.tools.dotc.reporting.Diagnostic;
 import dotty.tools.dotc.reporting.Message;
 import dotty.tools.dotc.util.SourceFile;
@@ -43,12 +46,13 @@ public void doReport(Diagnostic dia, Context ctx) {
     messageBuilder.append(message.message());
     String diagnosticCode = String.valueOf(message.errorId().errorNumber());
     boolean shouldExplain = Diagnostic.shouldExplain(dia, ctx);
+    List<CodeAction> actions = message.actions(ctx);
     if (shouldExplain && !message.explanation().isEmpty()) {
       rendered.append(explanation(message, ctx));
       messageBuilder.append(System.lineSeparator()).append(explanation(message, ctx));
     }
 
-    delegate.log(new Problem(position, messageBuilder.toString(), severity, rendered.toString(), diagnosticCode));
+    delegate.log(new Problem(position, messageBuilder.toString(), severity, rendered.toString(), diagnosticCode, actions));
   }
 
   private static Severity severityOf(int level) {

sbt-bridge/src/dotty/tools/xsbt/Problem.java

@@ -1,6 +1,13 @@
 package dotty.tools.xsbt;
 
+import java.util.List;
 import java.util.Optional;
+import static java.util.stream.Collectors.toList;
+
+import dotty.tools.dotc.reporting.CodeAction;
+import dotty.tools.dotc.rewrites.Rewrites.ActionPatch;
+import dotty.tools.dotc.util.SourcePosition;
+
 import xsbti.Position;
 import xsbti.Severity;
 
@@ -10,14 +17,16 @@ final public class Problem implements xsbti.Problem {
   private final Severity _severity;
   private final Optional<String> _rendered;
   private final String _diagnosticCode;
+  private final List<CodeAction> _actions;
 
-  public Problem(Position position, String message, Severity severity, String rendered, String diagnosticCode) {
+  public Problem(Position position, String message, Severity severity, String rendered, String diagnosticCode, List<CodeAction> actions) {
     super();
     this._position = position;
     this._message = message;
     this._severity = severity;
     this._rendered = Optional.of(rendered);
     this._diagnosticCode = diagnosticCode;
+    this._actions = actions;
   }
 
   public String category() {
@@ -56,6 +65,34 @@ public Optional<xsbti.DiagnosticCode> diagnosticCode() {
     }
   }
 
+  public List<xsbti.Action> actions() {
+    if (_actions.isEmpty()) {
+      return java.util.Collections.emptyList();
+    } else {
+      return _actions
+              .stream()
+              .map(action -> new Action(action.title(), action.description(), toWorkspaceEdit(action.patches())))
+              .collect(toList());
+    }
+  }
+
+  private static WorkspaceEdit toWorkspaceEdit(List<ActionPatch> patches) {
+    return new WorkspaceEdit(
+      patches
+        .stream()
+        .map(patch -> new TextEdit(positionOf(patch.srcPos()), patch.replacement()))
+        .collect(toList())
+    );
+  }
+
+  private static Position positionOf(SourcePosition pos) {
+    if (pos.exists()){
+      return new PositionBridge(pos, pos.source());
+    } else {
+      return PositionBridge.noPosition;
+    }
+  }
+
   @Override
   public String toString() {
     return "Problem(" + _position + ", " + _message + ", " + _severity + ", " + _rendered + ", " + _diagnosticCode + ")";

sbt-bridge/src/dotty/tools/xsbt/TextEdit.java

@@ -0,0 +1,23 @@
+package dotty.tools.xsbt;
+
+import xsbti.Position;
+
+final public class TextEdit implements xsbti.TextEdit {
+  private final Position _position;
+  private final String _newText;
+
+  public TextEdit(Position position, String newText) {
+    super();
+    this._position = position;
+    this._newText = newText;
+  }
+
+  public Position position() {
+    return _position;
+  }
+
+  public String newText() {
+    return _newText;
+  }
+
+}

sbt-bridge/src/dotty/tools/xsbt/WorkspaceEdit.java

@@ -0,0 +1,20 @@
+package dotty.tools.xsbt;
+
+import java.util.List;
+
+import xsbti.TextEdit;
+
+final public class WorkspaceEdit implements xsbti.WorkspaceEdit {
+
+  private final List<TextEdit> _changes;
+
+  public WorkspaceEdit(List<TextEdit> changes) {
+    super();
+    this._changes = changes;
+  }
+
+  public List<TextEdit> changes() {
+    return _changes;
+  }
+
+}

sbt-test/compilerReporter/simple/Source.scala

@@ -7,4 +7,7 @@ trait Wr {
 
 object Er {
   val a = er1
-}
+
+  def f: Int = 1
+  val x = f _
+}

sbt-test/compilerReporter/simple/project/Reporter.scala

@@ -27,27 +27,58 @@ object Reporter {
     check := (Compile / compile).failure.map(_ => {
       val problems = reporter.problems
       println(problems.toList)
-      assert(problems.size == 1)
 
-      // make sure position reported by zinc are proper
-      val mainProblem = problems.head
+      problems match {
+        case Array(err, warning) =>
+          // Checking the error reported
+          val eline = err.position().line()
+          assert(eline.isPresent() == true)
+          assert(eline.get() == 9)
 
-      val line = mainProblem.position().line()
-      assert(line.isPresent() == true)
-      assert(line.get() == 9)
+          val ediagnosticCode = err.diagnosticCode()
+          assert(ediagnosticCode.isPresent() == true)
+          val ecode = ediagnosticCode.get().code()
+          assert(ecode == "6")
 
-      val diagnosticCode = mainProblem.diagnosticCode()
-      assert(diagnosticCode.isPresent() == true)
-      val code = diagnosticCode.get()
-      assert(diagnosticCode.get().code() == "6")
+          val epointer = err.position().pointer()
+          assert(epointer.isPresent() == true)
+          assert(epointer.get() == 10)
 
-      val pointer = mainProblem.position().pointer()
-      assert(pointer.isPresent() == true)
-      assert(pointer.get() == 10)
+          assert(err.position.offset.isPresent)
 
-      assert(problems.forall(_.position.offset.isPresent))
+          assert(err.severity == Severity.Error) // not found: er1,
 
-      assert(problems.count(_.severity == Severity.Error) == 1) // not found: er1,
+          // Checking the warning reported
+
+          val wline = warning.position().line()
+          assert(wline.isPresent() == true)
+          assert(wline.get() == 12)
+
+          val wdiagnosticCode = warning.diagnosticCode()
+          assert(wdiagnosticCode.isPresent() == true)
+          val wcode = wdiagnosticCode.get().code()
+          assert(wcode == "99")
+
+          val wpointer = warning.position().pointer()
+          assert(wpointer.isPresent() == true)
+          assert(wpointer.get() == 12)
+
+          assert(warning.position.offset.isPresent)
+
+          assert(warning.severity == Severity.Warn) // Only function types can be followed by _ but the current expression has type Int
+
+          //val actions = warning.actions()
+
+          //assert(actions.size == 1)
+
+          //val action = actions.head
+
+          //assert(action.title() == "wrong")
+
+        case somethingElse =>
+          assert(false, s"Only expected to have a single error and a single warning, but instead got: ${somethingElse.toString}")
+
+      }
     }).value
   )
 }