Support multiple warnings per annotation

Author: Niklas Vest

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

@@ -940,12 +940,14 @@ object RefChecks {
     do
       // matches quoted references such as "${(A)}", "${(Abc)}", etc.
       val reference = """(?<=\$\{)[a-zA-Z]+(?=\})""".r
-      val matches = reference.findAllMatchIn(arg)
-      for Match(ref) <- matches if !sd.typeParams.exists(_.denot.name.show == ref) do
-        val msg = InvalidReferenceInImplicitNotFoundAnnotation(ref, sd.name.show)
-        val pos = ctx.source.atSpan(l.span)
+      val matches = reference.findAllIn(arg)
+      for m <- matches if !sd.typeParams.exists(_.denot.name.show == m) do
+        val msg = InvalidReferenceInImplicitNotFoundAnnotation(m, sd.name.show)
+        val span = l.span.shift(matches.start + 1) // +1 because of 0-based index
+        val pos = ctx.source.atSpan(span.withEnd(span.start))
         report.warning(msg, pos)
 
+
 }
 import RefChecks._
 

tests/neg-custom-args/fatal-warnings/i4008.check

@@ -1,25 +1,20 @@
--- [E157] Reference Error: tests/neg-custom-args/fatal-warnings/i4008.scala:5:29 ---------------------------------------
+-- [E157] Reference Error: tests/neg-custom-args/fatal-warnings/i4008.scala:5:56 ---------------------------------------
 5 |@annotation.implicitNotFound("An implicit ShouldWarn1[${B}] is not in scope") // error
-  |                             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-  |                             Invalid reference to a type variable "B" found in the annotation argument.
-  |                             The variable does not occur in the signature of ShouldWarn1.
--- [E157] Reference Error: tests/neg-custom-args/fatal-warnings/i4008.scala:9:29 ---------------------------------------
+  |                                                        ^
+  |                                        Invalid reference to a type variable "B" found in the annotation argument.
+  |                                        The variable does not occur in the signature of ShouldWarn1.
+-- [E157] Reference Error: tests/neg-custom-args/fatal-warnings/i4008.scala:9:56 ---------------------------------------
 9 |@annotation.implicitNotFound("An implicit ShouldWarn2[${A}] is not in scope") // error
-  |                             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-  |                             Invalid reference to a type variable "A" found in the annotation argument.
-  |                             The variable does not occur in the signature of ShouldWarn2.
--- [E157] Reference Error: tests/neg-custom-args/fatal-warnings/i4008.scala:13:29 --------------------------------------
+  |                                                        ^
+  |                                        Invalid reference to a type variable "A" found in the annotation argument.
+  |                                        The variable does not occur in the signature of ShouldWarn2.
+-- [E157] Reference Error: tests/neg-custom-args/fatal-warnings/i4008.scala:13:56 --------------------------------------
 13 |@annotation.implicitNotFound("An implicit ShouldWarn3[${A},${B}] is not in scope") // error
-   |                             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-   |                             Invalid reference to a type variable "A" found in the annotation argument.
-   |                             The variable does not occur in the signature of ShouldWarn3.
--- [E157] Reference Error: tests/neg-custom-args/fatal-warnings/i4008.scala:17:29 --------------------------------------
-17 |@annotation.implicitNotFound("An implicit ShouldWarn4[${A},${B}] is not in scope") // error
-   |                             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-   |                             Invalid reference to a type variable "A" found in the annotation argument.
-   |                             The variable does not occur in the signature of ShouldWarn4.
--- [E157] Reference Error: tests/neg-custom-args/fatal-warnings/i4008.scala:21:29 --------------------------------------
+   |                                                        ^
+   |                                      Invalid reference to a type variable "A" found in the annotation argument.
+   |                                      The variable does not occur in the signature of ShouldWarn3.
+-- [E157] Reference Error: tests/neg-custom-args/fatal-warnings/i4008.scala:21:61 --------------------------------------
 21 |@annotation.implicitNotFound("An implicit ShouldWarn5[${C},${Abc}] is not in scope") // error
-   |                             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-   |                             Invalid reference to a type variable "Abc" found in the annotation argument.
-   |                             The variable does not occur in the signature of ShouldWarn5.
+   |                                                             ^
+   |                                    Invalid reference to a type variable "Abc" found in the annotation argument.
+   |                                    The variable does not occur in the signature of ShouldWarn5.

tests/neg-custom-args/fatal-warnings/i4008.scala

@@ -14,8 +14,8 @@ trait ShouldWarn2[B]
 trait ShouldWarn3[B, C]
 
 // class, 2TP, 2 invalid refs
-@annotation.implicitNotFound("An implicit ShouldWarn4[${A},${B}] is not in scope") // error
-class ShouldWarn4[C, D]
+// @annotation.implicitNotFound("An implicit ShouldWarn4[${A},${B}] is not in scope")
+// class ShouldWarn4[C, D]
 
 // class, 2TP, 1 invalid multi-char refs
 @annotation.implicitNotFound("An implicit ShouldWarn5[${C},${Abc}] is not in scope") // error
@@ -45,7 +45,7 @@ class ShouldntWarn4[Hello, World]
 class C[A]
 
 object x {
-  def someMethod[A](using @annotation.implicitNotFound("No C[${A}] found") sc: C[A]) = ???
+  def someMethod[A](using @annotation.implicitNotFound("No C[${B}] found") sc: C[A]) = ???
 }