hg: lambda/lambda/langtools: 8012003: Method diagnostics resolution need to be simplified in some cases

[maurizio.cimadamore at oracle.com]

Changeset: 53cbb85eb634
Author:    mcimadamore
Date:      2013-04-11 19:26 +0100
URL:       http://hg.openjdk.java.net/lambda/lambda/langtools/rev/53cbb85eb634

8012003: Method diagnostics resolution need to be simplified in some cases

This patch adds a -Xdiags flag that can be set to either 'verbose' or 'compact' (latter being new default).
If 'compact' is chosen, javac will try to simplify complex method resolution diagnostics. Example:

Before:

Test.java:10: error: method m in class Test cannot be applied to given types;
        m(()->1);
        ^
  required: Runnable
  found: ()->1
  reason: argument mismatch; bad return type in lambda expression
      int cannot be converted to void

After:

Test.java:10: error: incompatible types: bad return type in lambda expression
        m(()->1);
              ^
    int cannot be converted to void

! src/share/classes/com/sun/tools/javac/comp/Attr.java
! src/share/classes/com/sun/tools/javac/comp/Resolve.java
! src/share/classes/com/sun/tools/javac/main/JavaCompiler.java
! src/share/classes/com/sun/tools/javac/main/Option.java
! src/share/classes/com/sun/tools/javac/resources/compiler.properties
! src/share/classes/com/sun/tools/javac/resources/javac.properties
! src/share/classes/com/sun/tools/javac/util/JCDiagnostic.java
! src/share/classes/com/sun/tools/javac/util/List.java
! src/share/classes/com/sun/tools/javac/util/Log.java
+ test/tools/javac/Diagnostics/compressed/T8012003a.java
+ test/tools/javac/Diagnostics/compressed/T8012003a.out
+ test/tools/javac/Diagnostics/compressed/T8012003b.java
+ test/tools/javac/Diagnostics/compressed/T8012003b.out
+ test/tools/javac/Diagnostics/compressed/T8012003c.java
+ test/tools/javac/Diagnostics/compressed/T8012003c.out
+ test/tools/javac/diags/examples/CompressedDiags.java
! test/tools/javac/diags/examples/KindnameConstructor.java
+ test/tools/javac/diags/examples/ProbFoundReqFragment.java
! test/tools/javac/lambda/TargetType66.out