Handle multiline messages in ConsoleReporter

5 files changed, 90 insertions, 75 deletions

diff --git a/src/dotty/tools/dotc/reporting/ConsoleReporter.scala b/src/dotty/tools/dotc/reporting/ConsoleReporter.scala
index 45933d954..d96ff48a4 100644
--- a/src/dotty/tools/dotc/reporting/ConsoleReporter.scala
+++ b/src/dotty/tools/dotc/reporting/ConsoleReporter.scala
@@ -32,24 +32,35 @@ class ConsoleReporter(
   def stripColor(str: String): String =
     str.replaceAll("\u001B\\[[;\\d]*m", "")
 
-  def sourceLine(pos: SourcePosition)(implicit ctx: Context): (String, Int) = {
-    val lineNum = s"${pos.line}:"
-    (lineNum + hl"${pos.lineContent.stripLineEnd}", lineNum.length)
-  }
+  def sourceLines(pos: SourcePosition)(implicit ctx: Context): (List[String], Int) = {
+    var maxLen = Int.MinValue
+    val lines = pos.lines
+      .map { lineNbr =>
+        val prefix = s"${lineNbr + 1} |"
+        maxLen = math.max(maxLen, prefix.length)
+        (prefix, pos.lineContent(lineNbr).stripLineEnd)
+      }
+      .map { case (prefix, line) =>
+        val lnum = Red(" " * math.max(0, maxLen - prefix.length) + prefix)
+        hl"$lnum$line"
+      }
 
-  def columnMarker(pos: SourcePosition, offset: Int)(implicit ctx: Context) =
-    if (pos.startLine == pos.endLine) {
-      val whitespace = " " * (pos.startColumn + offset)
-      val carets =
-        Red("^" * math.max(1, pos.endColumn - pos.startColumn))
+    (lines, maxLen)
+  }
 
-      whitespace + carets.show
-    } else {
-      Red(" " * (pos.column + offset) + "^").show
+  def columnMarker(pos: SourcePosition, offset: Int)(implicit ctx: Context) = {
+    val prefix = " " * (offset - 1)
+    val whitespace = " " * pos.startColumn
+    val carets = Red {
+      if (pos.startLine == pos.endLine)
+        "^" * math.max(1, pos.endColumn - pos.startColumn)
+      else "^"
     }
 
+    s"$prefix|$whitespace${carets.show}"
+  }
+
   def errorMsg(pos: SourcePosition, msg: String, offset: Int)(implicit ctx: Context) = {
-    var hasLongLines = false
     val leastWhitespace = msg.lines.foldLeft(Int.MaxValue) { (minPad, line) =>
       val lineLength = stripColor(line).length
       val padding =
@@ -59,9 +70,8 @@ class ConsoleReporter(
       else minPad
     }
 
-    msg
-      .lines
-      .map { line => " " * leastWhitespace + line }
+    msg.lines
+      .map { line => " " * (offset - 1) + "|" + (" " * (leastWhitespace - offset)) + line }
       .mkString(sys.props("line.separator"))
   }
 
@@ -85,11 +95,11 @@ class ConsoleReporter(
   def printMessageAndPos(msg: Message, pos: SourcePosition, diagnosticLevel: String)(implicit ctx: Context): Unit = {
     printMessage(posStr(pos, diagnosticLevel, msg))
     if (pos.exists) {
-      val (src, offset) = sourceLine(pos)
+      val (srcLines, offset) = sourceLines(pos)
       val marker = columnMarker(pos, offset)
       val err = errorMsg(pos, msg.msg, offset)
 
-      printMessage(List(src, marker, err).mkString("\n"))
+      printMessage((srcLines ::: marker :: err :: Nil).mkString("\n"))
     } else printMessage(msg.msg)
   }
 
diff --git a/src/dotty/tools/dotc/util/SourceFile.scala b/src/dotty/tools/dotc/util/SourceFile.scala
index 8bd0ecfd6..1d4c9c2ab 100644
--- a/src/dotty/tools/dotc/util/SourceFile.scala
+++ b/src/dotty/tools/dotc/util/SourceFile.scala
@@ -97,7 +97,7 @@ case class SourceFile(file: AbstractFile, content: Array[Char]) extends interfac
   private lazy val lineIndices: Array[Int] = calculateLineIndices(content)
 
   /** Map line to offset of first character in line */
-  def lineToOffset(index : Int): Int = lineIndices(index)
+  def lineToOffset(index: Int): Int = lineIndices(index)
 
   /** A cache to speed up offsetToLine searches to similar lines */
   private var lastLine = 0
diff --git a/src/dotty/tools/dotc/util/SourcePosition.scala b/src/dotty/tools/dotc/util/SourcePosition.scala
index 68a9b6403..d0f9cb887 100644
--- a/src/dotty/tools/dotc/util/SourcePosition.scala
+++ b/src/dotty/tools/dotc/util/SourcePosition.scala
@@ -14,6 +14,17 @@ extends interfaces.SourcePosition {
   def point: Int = pos.point
   /** The line of the position, starting at 0 */
   def line: Int = source.offsetToLine(point)
+
+  /** The lines of the position */
+  def lines: List[Int] =
+    List.range(source.offsetToLine(start), source.offsetToLine(end)) match {
+      case Nil => line :: Nil
+      case xs => xs
+    }
+
+  def lineContent(lineNumber: Int): String =
+    source.lineContent(source.lineToOffset(lineNumber))
+
   /** The column of the position, starting at 0 */
   def column: Int = source.column(point)
 
diff --git a/tests/repl/errmsgs.check b/tests/repl/errmsgs.check
index b8cff5ba2..2a65fd949 100644
--- a/tests/repl/errmsgs.check
+++ b/tests/repl/errmsgs.check
@@ -2,46 +2,46 @@ scala> class Inv[T](x: T)
 defined class Inv
 scala> val x: List[String] = List(1)
 -- [E006] Type Mismatch Error: <console> -------------------------------------------------------------------------------
-3:val x: List[String] = List(1)
-                             ^
-                             found:    Int(1)
-                             required: String
-                             
+4 |val x: List[String] = List(1)
+  |                           ^
+  |                           found:    Int(1)
+  |                           required: String
+  |                           
 scala> val y: List[List[String]] = List(List(1))
 -- [E006] Type Mismatch Error: <console> -------------------------------------------------------------------------------
-3:val y: List[List[String]] = List(List(1))
-                                        ^
-                                        found:    Int(1)
-                                        required: String
-                                        
+4 |val y: List[List[String]] = List(List(1))
+  |                                      ^
+  |                                      found:    Int(1)
+  |                                      required: String
+  |                                      
 scala> val z: (List[String], List[Int]) = (List(1), List("a"))
 -- [E006] Type Mismatch Error: <console> -------------------------------------------------------------------------------
-3:val z: (List[String], List[Int]) = (List(1), List("a"))
-                                           ^
-                                           found:    Int(1)
-                                           required: String
-                                           
+4 |val z: (List[String], List[Int]) = (List(1), List("a"))
+  |                                         ^
+  |                                         found:    Int(1)
+  |                                         required: String
+  |                                         
 -- [E006] Type Mismatch Error: <console> -------------------------------------------------------------------------------
-3:val z: (List[String], List[Int]) = (List(1), List("a"))
-                                                    ^^^
-                                                    found:    String("a")
-                                                    required: Int
-                                                    
+4 |val z: (List[String], List[Int]) = (List(1), List("a"))
+  |                                                  ^^^
+  |                                                  found:    String("a")
+  |                                                  required: Int
+  |                                                  
 scala> val a: Inv[String] = new Inv(new Inv(1))
 -- [E006] Type Mismatch Error: <console> -------------------------------------------------------------------------------
-4:val a: Inv[String] = new Inv(new Inv(1))
-                                   ^^^^^
-                                   found:    Inv[T]
-                                   required: String
-                                   
-                                   where:    T is a type variable with constraint >: Int(1)
+5 |val a: Inv[String] = new Inv(new Inv(1))
+  |                                 ^^^^^
+  |                                 found:    Inv[T]
+  |                                 required: String
+  |                                 
+  |                                 where:    T is a type variable with constraint >: Int(1)
 scala> val b: Inv[String] = new Inv(1)
 -- [E006] Type Mismatch Error: <console> -------------------------------------------------------------------------------
-4:val b: Inv[String] = new Inv(1)
-                               ^
-                               found:    Int(1)
-                               required: String
-                               
+5 |val b: Inv[String] = new Inv(1)
+  |                             ^
+  |                             found:    Int(1)
+  |                             required: String
+  |                             
 scala> abstract class C {
            type T
            val x: T
@@ -58,19 +58,19 @@ scala> abstract class C {
            }
          }
 -- [E006] Type Mismatch Error: <console> -------------------------------------------------------------------------------
-8:      var y: T = x
-                   ^
-                   found:    C.this.T(C.this.x)
-                   required: T'
-                   
-                   where:    T  is a type in class C
-                             T' is a type in the initalizer of value s which is an alias of String
+9 |      var y: T = x
+  |                 ^
+  |                 found:    C.this.T(C.this.x)
+  |                 required: T'
+  |                 
+  |                 where:    T  is a type in class C
+  |                           T' is a type in the initalizer of value s which is an alias of String
 -- [E006] Type Mismatch Error: <console> -------------------------------------------------------------------------------
-12:          val z: T = y
-                        ^
-                        found:    T(y)
-                        required: T'
-                        
-                        where:    T  is a type in the initalizer of value s which is an alias of String
-                                  T' is a type in method f which is an alias of Int
+13 |          val z: T = y
+   |                     ^
+   |                     found:    T(y)
+   |                     required: T'
+   |                     
+   |                     where:    T  is a type in the initalizer of value s which is an alias of String
+   |                               T' is a type in method f which is an alias of Int
 scala> :quit
diff --git a/tests/repl/imports.check b/tests/repl/imports.check
index 2e8d5dcf9..9743d2b94 100644
--- a/tests/repl/imports.check
+++ b/tests/repl/imports.check
@@ -8,17 +8,11 @@ scala> import o._
 import o._
 scala> buf += xs
 -- [E006] Type Mismatch Error: <console> -------------------------------------------------------------------------------
-10:buf += xs
-          ^^
-          found:    scala.collection.immutable.List[Int](o.xs)
-          required: String
-          
--- [E006] Type Mismatch Error: <console> -------------------------------------------------------------------------------
-10:buf += xs
-   ^^^^^^^^^
-   found:    String
-   required: scala.collection.mutable.ListBuffer[Int]
-   
+11 |buf += xs
+   |       ^^
+   |       found:    scala.collection.immutable.List[Int](o.xs)
+   |       required: String
+   |       
 scala> buf ++= xs
 res1: scala.collection.mutable.ListBuffer[Int] = ListBuffer(1, 2, 3)
 scala> :quit