Refine error message

Author: liufengyun

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

@@ -673,6 +673,8 @@ object Semantic:
             if obj.hasField(target) then
               obj.field(target)
             else if ref.isInstanceOf[Warm] then
+              if !target.exists then
+                println("obj.klass = " + obj.klass.show + ", field = " + field.show)
               assert(obj.klass.isSubClass(target.owner))
               if target.is(Flags.ParamAccessor) then
                 // possible for trait parameters
@@ -1231,7 +1233,7 @@ 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.\nFound = " + value.show + ". ")
+      value.promote("Cannot prove the method 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`