Rip out reporting indirection from CompilationUnit

Inline the forwarders from CompilationUnit, which should not affect behavior.
Since all forwarders lead to global.reporter, don't first navigate
to a compilation unit, only to then forward back to global.reporter.

The cleanup in the previous commits revealed a ton of confusion
regarding how to report an error.

This was a mechanical search/replace, which has low potential for messing
things up, since the list of available methods are disjoint between
`reporter` and `currentRun.reporting`. The changes involving `typer.context`
were done previously.

Essentially, there are three ways to report:
  - via typer.context, so that reporting can be silenced (buffered)
  - via global.currentRun.reporting, which summarizes (e.g., deprecation)
  - via global.reporter, which is (mostly) stateless and straightforward.

Ideally, these should all just go through `global.currentRun.reporting`,
with the typing context changing that reporter to buffer where necessary.

After the refactor, these are the ways in which we report (outside of typer):
  - reporter.comment
  - reporter.echo
  - reporter.error
  - reporter.warning
  - currentRun.reporting.deprecationWarning
  - currentRun.reporting.incompleteHandled
  - currentRun.reporting.incompleteInputError
  - currentRun.reporting.inlinerWarning
  - currentRun.reporting.uncheckedWarning

Before:
  - c.cunit.error
  - c.enclosingUnit.deprecationWarning
  - context.unit.error
  - context.unit.warning
  - csymCompUnit.warning
  - cunit.error
  - cunit.warning
  - currentClass.cunit.warning
  - currentIClazz.cunit.inlinerWarning
  - currentRun.currentUnit.error
  - currentRun.reporting
  - currentUnit.deprecationWarning
  - currentUnit.error
  - currentUnit.warning
  - getContext.unit.warning
  - getCurrentCUnit.error
  - global.currentUnit.uncheckedWarning
  - global.currentUnit.warning
  - global.reporter
  - icls.cunit.warning
  - item.cunit.warning
  - reporter.comment
  - reporter.echo
  - reporter.error
  - reporter.warning
  - reporting.deprecationWarning
  - reporting.incompleteHandled
  - reporting.incompleteInputError
  - reporting.inlinerWarning
  - reporting.uncheckedWarning
  - typer.context.unit.warning
  - unit.deprecationWarning
  - unit.echo
  - unit.error
  - unit.incompleteHandled
  - unit.incompleteInputError
  - unit.uncheckedWarning
  - unit.warning
  - v1.cunit.warning

All these methods ended up calling a method on `global.reporter`
or on `global.currentRun.reporting` (their interfaces are disjoint).

Also clean up `TypeDiagnostics`: inline nearly-single-use private methods.

1 files changed, 3 insertions, 3 deletions

diff --git a/src/compiler/scala/tools/nsc/transform/patmat/PatternMatching.scala b/src/compiler/scala/tools/nsc/transform/patmat/PatternMatching.scala
index f6c960d089..ef50e083a1 100644
--- a/src/compiler/scala/tools/nsc/transform/patmat/PatternMatching.scala
+++ b/src/compiler/scala/tools/nsc/transform/patmat/PatternMatching.scala
@@ -65,7 +65,7 @@ trait PatternMatching extends Transform
         } catch {
           case x: (Types#TypeError) =>
             // TODO: this should never happen; error should've been reported during type checking
-            unit.error(tree.pos, "error during expansion of this match (this is a scalac bug).\nThe underlying error was: "+ x.msg)
+            reporter.error(tree.pos, "error during expansion of this match (this is a scalac bug).\nThe underlying error was: "+ x.msg)
             translated
         }
       case Try(block, catches, finalizer) =>
@@ -175,13 +175,13 @@ trait Interface extends ast.TreeDSL {
     val matchOwner = typer.context.owner
     def pureType(tp: Type): Type = tp
 
-    def reportUnreachable(pos: Position) = typer.context.unit.warning(pos, "unreachable code")
+    def reportUnreachable(pos: Position) = reporter.warning(pos, "unreachable code")
     def reportMissingCases(pos: Position, counterExamples: List[String]) = {
       val ceString =
         if (counterExamples.tail.isEmpty) "input: " + counterExamples.head
         else "inputs: " + counterExamples.mkString(", ")
 
-      typer.context.unit.warning(pos, "match may not be exhaustive.\nIt would fail on the following "+ ceString)
+      reporter.warning(pos, "match may not be exhaustive.\nIt would fail on the following "+ ceString)
     }
   }