Use precise consume reason

Author: Linyxus

compiler/src/dotty/tools/dotc/cc/SepCheck.scala

@@ -461,10 +461,7 @@ class SepCheck(checker: CheckCaptures.CheckerAPI) extends tpd.TreeTraverser:
    */
   def consumeError(ref: Capability, loc: (SrcPos, TypeRole), pos: SrcPos)(using Context): Unit =
     val (locPos, role) = loc
-    report.error(
-      em"""Separation failure: Illegal access to $ref, which was ${role.howConsumed}
-          |on line ${locPos.line + 1} and therefore is no longer available.""",
-      pos)
+    report.error(reporting.UseAfterConsume(ref, locPos.sourcePos, pos.sourcePos, role.howConsumed), pos)
 
   /** Report a failure where a capability is consumed in a loop.
    *  @param ref     the capability

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

@@ -3742,11 +3742,10 @@ final class EncodedPackageName(name: Name)(using Context) extends SyntaxMsg(Enco
        |
        |In this case, the name `$name` is encoded as `${name.encode}`."""
 
-class UseAfterConsume(ref: cc.Capabilities.Capability, consumedLoc: SourcePosition, useLoc: SourcePosition)(using Context)
+class UseAfterConsume(ref: cc.Capabilities.Capability, consumedLoc: SourcePosition, useLoc: SourcePosition, howConsumed: => String)(using Context)
 extends TypeMsg(NoExplanationID):
   protected def msg(using Context): String =
-    i"""Separation failure: Illegal access to $ref, which was passed to a
-       |consume parameter or was used as a prefix to a consume method
+    i"""Separation failure: Illegal access to $ref, which was $howConsumed
        |and therefore is no longer available."""
 
   protected def explain(using Context): String = ""

tests/neg-custom-args/captures/consume-twice-same-line.check

@@ -1,6 +1,5 @@
 -- Type Error: tests/neg-custom-args/captures/consume-twice-same-line.scala:5:16 ---------------------------------------
-Separation failure: Illegal access to (x : Object^), which was passed to a
-consume parameter or was used as a prefix to a consume method
+Separation failure: Illegal access to (x : Object^), which was passed as a consume parameter to method send
 and therefore is no longer available.
 
 where:    ^ refers to a fresh root capability in the type of parameter x
@@ -10,8 +9,7 @@ where:    ^ refers to a fresh root capability in the type of parameter x
   |       The capability was consumed here.
 
 -- Type Error: tests/neg-custom-args/captures/consume-twice-same-line.scala:8:16 ---------------------------------------
-Separation failure: Illegal access to (x : Object^), which was passed to a
-consume parameter or was used as a prefix to a consume method
+Separation failure: Illegal access to (x : Object^), which was passed as a consume parameter to method send
 and therefore is no longer available.
 
 where:    ^ refers to a fresh root capability in the type of parameter x
@@ -21,8 +19,7 @@ where:    ^ refers to a fresh root capability in the type of parameter x
   |       The capability was consumed here.
 
 -- Type Error: tests/neg-custom-args/captures/consume-twice-same-line.scala:8:25 ---------------------------------------
-Separation failure: Illegal access to (x : Object^), which was passed to a
-consume parameter or was used as a prefix to a consume method
+Separation failure: Illegal access to (x : Object^), which was passed as a consume parameter to method send
 and therefore is no longer available.
 
 where:    ^ refers to a fresh root capability in the type of parameter x

tests/neg-custom-args/captures/consume-twice.check

@@ -1,6 +1,5 @@
 -- Type Error: tests/neg-custom-args/captures/consume-twice.scala:6:7 --------------------------------------------------
-Separation failure: Illegal access to (x : Object^), which was passed to a
-consume parameter or was used as a prefix to a consume method
+Separation failure: Illegal access to (x : Object^), which was passed as a consume parameter to method send
 and therefore is no longer available.
 
 where:    ^ refers to a fresh root capability in the type of parameter x