SI-7319 Clear error buffer during Typer reset.

Contexts share error/warning buffers with their
children, and this also applies ot the shared
`startContext`.

That context flushes the buffers in `startContext`
in `resetContexts`.

It also removes `typerReportAnyContextErrors`, which
appears to be an elaborate no-op. It is only ever passed
a context `c` which is a direct child of `this.context`.
So taking a buffered error out of `c` and reissuing it
into `this.context` merely re-inserts into into the same
error buffer. Consrast this with `silent`, which uses
a child context with a fresh error buffer.

SI-7319 Flush error buffer in typerReportAnyContextErrors.

After this change, we no longer rely on the backstop in resetContexts
introduced in the previous commit.

1 files changed, 12 insertions, 18 deletions

diff --git a/src/compiler/scala/tools/nsc/typechecker/Typers.scala b/src/compiler/scala/tools/nsc/typechecker/Typers.scala
index d1d6feae97..d3e9192066 100644
--- a/src/compiler/scala/tools/nsc/typechecker/Typers.scala
+++ b/src/compiler/scala/tools/nsc/typechecker/Typers.scala
@@ -507,10 +507,7 @@ trait Typers extends Modes with Adaptations with Tags {
 
     @inline
     final def typerReportAnyContextErrors[T](c: Context)(f: Typer => T): T = {
-      val res = f(newTyper(c))
-      if (c.hasErrors)
-        context.issue(c.errBuffer.head)
-      res
+      f(newTyper(c))
     }
 
     @inline
@@ -1747,9 +1744,7 @@ trait Typers extends Modes with Adaptations with Tags {
       assert(clazz != NoSymbol, cdef)
       reenterTypeParams(cdef.tparams)
       val tparams1 = cdef.tparams mapConserve (typedTypeDef)
-      val impl1 = typerReportAnyContextErrors(context.make(cdef.impl, clazz, newScope)) {
-        _.typedTemplate(cdef.impl, parentTypes(cdef.impl))
-      }
+      val impl1 = newTyper(context.make(cdef.impl, clazz, newScope)).typedTemplate(cdef.impl, parentTypes(cdef.impl))
       val impl2 = finishMethodSynthesis(impl1, clazz, context)
       if (clazz.isTrait && clazz.info.parents.nonEmpty && clazz.info.firstParent.typeSymbol == AnyClass)
         checkEphemeral(clazz, impl2.body)
@@ -1790,17 +1785,16 @@ trait Typers extends Modes with Adaptations with Tags {
         || !linkedClass.isSerializable
         || clazz.isSerializable
       )
-      val impl1 = typerReportAnyContextErrors(context.make(mdef.impl, clazz, newScope)) {
-        _.typedTemplate(mdef.impl, {
-          parentTypes(mdef.impl) ++ (
-            if (noSerializable) Nil
-            else {
-              clazz.makeSerializable()
-              List(TypeTree(SerializableClass.tpe) setPos clazz.pos.focus)
-            }
-          )
-        })
-      }
+      val impl1 = newTyper(context.make(mdef.impl, clazz, newScope)).typedTemplate(mdef.impl, {
+        parentTypes(mdef.impl) ++ (
+          if (noSerializable) Nil
+          else {
+            clazz.makeSerializable()
+            List(TypeTree(SerializableClass.tpe) setPos clazz.pos.focus)
+          }
+        )
+      })
+
       val impl2  = finishMethodSynthesis(impl1, clazz, context)
 
       // SI-5954. On second compile of a companion class contained in a package object we end up