Complete better structure to diagnostic messages

Author: felixmulder

src/dotty/tools/dotc/config/ScalaSettings.scala

@@ -23,7 +23,7 @@ class ScalaSettings extends Settings.SettingGroup {
   val migration = BooleanSetting("-migration", "Emit warning and location for migration issues from Scala 2.")
   val encoding = StringSetting("-encoding", "encoding", "Specify character encoding used by source files.", Properties.sourceEncoding)
   val explaintypes = BooleanSetting("-explaintypes", "Explain type errors in more detail.")
-  val explainerrors = BooleanSetting("-explain", "Explain errors in more detail.")
+  val explain = BooleanSetting("-explain", "Explain errors in more detail.")
   val feature = BooleanSetting("-feature", "Emit warning and location for usages of features that should be imported explicitly.")
   val g = ChoiceSetting("-g", "level", "Set level of generated debugging info.", List("none", "source", "line", "vars", "notailcalls"), "vars")
   val help = BooleanSetting("-help", "Print a synopsis of standard options")

src/dotty/tools/dotc/parsing/JavaParsers.scala

@@ -29,7 +29,7 @@ import scala.reflect.internal.util.Collections._
 object JavaParsers {
 
   import ast.untpd._
-  import reporting.ErrorMessages.Syntax._
+  import reporting.diagnostic.syntax._
 
   class JavaParser(source: SourceFile)(implicit ctx: Context) extends ParserCommon(source) {
 

src/dotty/tools/dotc/parsing/MarkupParsers.scala

@@ -32,7 +32,7 @@ import Utility._
 object MarkupParsers {
 
   import ast.untpd._
-  import reporting.ErrorMessages.Syntax._
+  import reporting.diagnostic.syntax._
 
   case object MissingEndTagControl extends ControlThrowable {
     override def getMessage = "start tag was here: "

src/dotty/tools/dotc/parsing/Parsers.scala

@@ -17,7 +17,6 @@ import ast.Trees._
 import Decorators._
 import StdNames._
 import util.Positions._
-import reporting.ErrorMessages._
 import Constants._
 import ScriptParsers._
 import scala.annotation.{tailrec, switch}
@@ -28,7 +27,9 @@ import Scanners.Comment
 object Parsers {
 
   import ast.untpd._
-  import reporting.ErrorMessages.Syntax._
+  import reporting.diagnostic.MessageCreator
+  import MessageCreator._
+  import reporting.diagnostic.syntax._
 
   case class OpInfo(operand: Tree, operator: Name, offset: Offset)
 
@@ -88,7 +89,7 @@ object Parsers {
     /** Issue an error at given offset if beyond last error offset
       *  and update lastErrorOffset.
       */
-    def syntaxError(expl: ErrorMessage, offset: Int = in.offset): Unit =
+    def syntaxError(expl: MessageCreator, offset: Int = in.offset): Unit =
       if (offset > lastErrorOffset) {
         syntaxError(expl, Position(offset))
         lastErrorOffset = in.offset
@@ -97,7 +98,7 @@ object Parsers {
     /** Unconditionally issue an error at given position, without
       *  updating lastErrorOffset.
       */
-    def syntaxError(expl: ErrorMessage, pos: Position): Unit =
+    def syntaxError(expl: MessageCreator, pos: Position): Unit =
       ctx.explainError(expl, source atPos pos)
 
   }
@@ -204,7 +205,7 @@ object Parsers {
       }
     }
 
-    def warning(msg: ErrorMessage, offset: Int = in.offset) =
+    def warning(msg: MessageCreator, offset: Int = in.offset) =
       ctx.explainWarning(msg, source atPos Position(offset))
 
     def deprecationWarning(msg: String, offset: Int = in.offset) =
@@ -1014,7 +1015,7 @@ object Parsers {
 
           handler match {
             case Block(Nil, EmptyTree) =>
-              syntaxError(EmptyCatchBlock(body), handler.pos)
+              syntaxError(new EmptyCatchBlock(body), handler.pos)
             case _ =>
           }
 

src/dotty/tools/dotc/reporting/ConsoleReporter.scala

@@ -9,7 +9,7 @@ import Reporter._
 import java.io.{ BufferedReader, IOException, PrintWriter }
 import scala.reflect.internal.util._
 import diagnostic.Message
-import diagnostic.basic._
+import diagnostic.messages._
 
 /**
  * This class implements a Reporter that displays messages on a text

src/dotty/tools/dotc/reporting/ErrorMessages.scala

@@ -10,9 +10,9 @@ import config.Printers
 import java.lang.System.currentTimeMillis
 import core.Mode
 import dotty.tools.dotc.core.Symbols.Symbol
-import diagnostic.Message
-import ErrorMessages._
-import diagnostic.basic._
+import diagnostic.messages._
+import diagnostic._
+import MessageCreator._
 
 object Reporter {
   /** Convert a SimpleReporter into a real Reporter */
@@ -75,10 +75,10 @@ trait Reporting { this: Context =>
   def warning(msg: => String, pos: SourcePosition = NoSourcePosition): Unit =
     reporter.report(new Warning(msg, pos))
 
-  def explainWarning(err: => ErrorMessage, pos: SourcePosition = NoSourcePosition): Unit = {
-    reporter.report(new Warning(err.msg, pos, s"${err.kind} warning"))
-    if (this.shouldExplain(err))
-      reporter.report(new Info(err.explanation, NoSourcePosition))
+  def explainWarning(msg: => MessageCreator, pos: SourcePosition = NoSourcePosition): Unit = {
+    reporter.report(msg.warning(pos))
+    if (this.shouldExplain(msg))
+      reporter.report(new Info(msg.explanation, NoSourcePosition))
   }
 
   def strictWarning(msg: => String, pos: SourcePosition = NoSourcePosition): Unit =
@@ -90,10 +90,10 @@ trait Reporting { this: Context =>
     reporter.report(new Error(msg, pos))
   }
 
-  def explainError(err: => ErrorMessage, pos: SourcePosition = NoSourcePosition): Unit = {
-    reporter.report(new Error(err.msg, pos, s"${err.kind} error"))
-    if (this.shouldExplain(err))
-      reporter.report(new Info(err.explanation, NoSourcePosition))
+  def explainError(msg: => MessageCreator, pos: SourcePosition = NoSourcePosition): Unit = {
+    reporter.report(msg.error(pos))
+    if (this.shouldExplain(msg))
+      reporter.report(new Info(msg.explanation, NoSourcePosition))
   }
 
   def errorOrMigrationWarning(msg: => String, pos: SourcePosition = NoSourcePosition): Unit =

src/dotty/tools/dotc/reporting/Reporter.scala

@@ -6,7 +6,7 @@ import core.Contexts.Context
 import collection.mutable
 import config.Printers._
 import diagnostic.Message
-import diagnostic.basic._
+import diagnostic.messages._
 
 /**
  * This class implements a Reporter that stores all messages

src/dotty/tools/dotc/reporting/StoreReporter.scala

@@ -5,7 +5,7 @@ package reporting
 import core.Contexts.Context
 import collection.mutable
 import diagnostic.Message
-import diagnostic.basic.Error
+import diagnostic.messages.Error
 import Reporter._
 
 /**

src/dotty/tools/dotc/reporting/ThrowingReporter.scala

@@ -4,6 +4,7 @@ package reporting
 package diagnostic
 
 import util.SourcePosition
+import core.Contexts.Context
 
 import java.util.Optional
 
@@ -55,9 +56,3 @@ class Message(
   override def toString = s"$getClass at $pos: $message"
   override def getMessage() = message
 }
-
-object NoExplanation {
-  def unapply(m: Message): Option[Message] =
-    if (m.explanation == "") Some(m)
-    else None
-}

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

@@ -0,0 +1,63 @@
+package dotty.tools
+package dotc
+package reporting
+package diagnostic
+
+import util.{SourcePosition, NoSourcePosition}
+import core.Contexts.Context
+
+object MessageCreator {
+  implicit class DiagnosticContext(val c: Context) extends AnyVal {
+    def shouldExplain(msg: MessageCreator): Boolean = {
+      implicit val ctx: Context = c
+      msg match {
+        case NoExplanation(_) => false
+        case _ => ctx.settings.explain.value
+      }
+    }
+  }
+
+  implicit def toNoExplanation(str: String) =
+    new NoExplanation(str)
+}
+
+trait MessageCreator {
+  import messages._
+
+  val msgFn: String = msg
+  def msg: String
+  def kind: String
+  def explanation: String
+
+  def error(pos: SourcePosition) =
+    new Error(msgFn, pos, kind, explanation)
+
+  def warning(pos: SourcePosition) =
+    new Warning(msgFn, pos, kind, explanation)
+
+  def info(pos: SourcePosition) =
+    new Info(msgFn, pos, kind, explanation)
+
+  def featureWarnign(pos: SourcePosition) =
+    new FeatureWarning(msgFn, pos, kind, explanation)
+
+  def uncheckedWarning(pos: SourcePosition) =
+    new UncheckedWarning(msgFn, pos, kind, explanation)
+
+  def deprecationWarning(pos: SourcePosition) =
+    new DeprecationWarning(msgFn, pos, kind, explanation)
+
+  def migrationWarning(pos: SourcePosition) =
+    new MigrationWarning(msgFn, pos, kind, explanation)
+}
+
+class NoExplanation(val msg: String) extends MessageCreator {
+  val explanation = ""
+  val kind = ""
+}
+
+object NoExplanation {
+  def unapply(m: MessageCreator): Option[MessageCreator] =
+    if (m.explanation == "") Some(m)
+    else None
+}

src/dotty/tools/dotc/reporting/diagnostic/MessageCreator.scala

@@ -9,7 +9,7 @@ import util.{SourcePosition, NoSourcePosition}
 import config.Settings.Setting
 import interfaces.Diagnostic.{ERROR, WARNING, INFO}
 
-object basic {
+object messages {
 
   class Error(
     msgFn: => String,