Refine error messages

Author: liufengyun

compiler/src/dotty/tools/dotc/transform/init/Errors.scala

@@ -82,11 +82,11 @@ object Errors:
 
   case class AccessCold(field: Symbol, trace: Seq[Tree]) extends Error:
     def show(using Context): String =
-      "Access field on a value with an unknown initialization status." + stacktrace()
+      "Access field " + field.show +  " on a value with a cold object." + stacktrace()
 
   case class CallCold(meth: Symbol, trace: Seq[Tree]) extends Error:
     def show(using Context): String =
-      "Call method on a value with an unknown initialization." + stacktrace()
+      "Call method " + meth.show + " on a value with an cold object." + stacktrace()
 
   case class CallUnknown(meth: Symbol, trace: Seq[Tree]) extends Error:
     def show(using Context): String =

compiler/src/dotty/tools/dotc/transform/init/Semantic.scala

@@ -56,7 +56,8 @@ object Semantic:
       case ThisRef(klass) =>
         "ThisRef[" + klass.show + "]"
       case Warm(klass, outer, ctor, args) =>
-        "Warm[" + klass.show + "] { outer = " + outer.show + ", args = " + args.map(_.show).mkString("(", ", ", ")") + " }"
+        val argsText = if args.nonEmpty then ", args = " + args.map(_.show).mkString("(", ", ", ")") else ""
+        "Warm[" + klass.show + "] { outer = " + outer.show + argsText + " }"
       case Fun(expr, thisV, klass) =>
         "Fun { this = " + thisV.show + ", owner = " + klass.show + " }"
       case RefSet(values) =>
@@ -1080,7 +1081,7 @@ object Semantic:
                 eval(body, thisV, klass)
               }
               given Trace = Trace.empty.add(body)
-              res.promote("The function return value is not fully initialized.")
+              res.promote("The function return value is not fully initialized. Found = " + res.show + ". ")
             }
             if errors.nonEmpty then
               reporter.report(UnsafePromotion(msg, trace.toVector, errors.head))
@@ -1124,12 +1125,12 @@ object Semantic:
                 withTrace(Trace.empty) {
                   val args = member.info.paramInfoss.flatten.map(_ => ArgInfo(Hot, Trace.empty))
                   val res = warm.call(member, args, receiver = NoType, superType = NoType)
-                  res.promote("Cannot prove that the return value of " + member + " is fully initialized.")
+                  res.promote("Cannot prove that the return value of " + member.show + " is fully initialized. Found = " + res.show + ". ")
                 }
               else
                 withTrace(Trace.empty) {
                   val res = warm.select(member)
-                  res.promote("Cannot prove that the field " + member + " is fully initialized.")
+                  res.promote("Cannot prove that the field " + member.show + " is fully initialized. Found = " + res.show + ". ")
                 }
           end for
         end for
@@ -1230,7 +1231,7 @@ object Semantic:
   /** Utility definition used for better error-reporting of argument errors */
   case class ArgInfo(value: Value, trace: Trace):
     def promote: Contextual[Unit] = withTrace(trace) {
-      value.promote("Cannot prove the argument is fully initialized. Only fully initialized values are safe to leak.")
+      value.promote("Cannot prove the argument is fully initialized. Only fully initialized values are safe to leak. \nFound = " + value.show + ". ")
     }
 
   /** Evaluate an expression with the given value for `this` in a given class `klass`
@@ -1395,14 +1396,14 @@ object Semantic:
       case Match(selector, cases) =>
         val res = eval(selector, thisV, klass)
         extendTrace(selector) {
-          res.ensureHot("The value to be matched needs to be fully initialized.")
+          res.ensureHot("The value to be matched needs to be fully initialized. Found = " + res.show + ". ")
         }
         eval(cases.map(_.body), thisV, klass).join
 
       case Return(expr, from) =>
         val res = eval(expr, thisV, klass)
         extendTrace(expr) {
-          res.ensureHot("return expression must be fully initialized.")
+          res.ensureHot("return expression must be fully initialized. Found = " + res.show + ". ")
         }
 
       case WhileDo(cond, body) =>