[commit: ghc] master: Add caret diagnostics (158530a)

[git at git.haskell.org]

Repository : ssh://git@git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/158530a5450b27eb5ae2d75b7895fd1662dde13b/ghc

>---------------------------------------------------------------

commit 158530a5450b27eb5ae2d75b7895fd1662dde13b
Author: Phil Ruffwind <rf at rufflewind.com>
Date:   Thu Dec 22 17:06:51 2016 -0500

    Add caret diagnostics
    
    This is controlled by -f[no-]diagnostics-show-caret.
    
    Example of what it looks like:
    ```
        |
     42 |     x = 1 + ()
        |         ^^^^^^
    ```
    This is appended to each diagnostic message.
    
    Test Plan:
    testsuite/tests/warnings/should_fail/CaretDiagnostics1
    testsuite/tests/warnings/should_fail/CaretDiagnostics2
    
    Reviewers: simonpj, austin, bgamari
    
    Reviewed By: simonpj, bgamari
    
    Subscribers: joehillen, mpickering, Phyx, simonpj, alanz, thomie
    
    Differential Revision: https://phabricator.haskell.org/D2718
    
    GHC Trac Issues: #8809


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158530a5450b27eb5ae2d75b7895fd1662dde13b
 .arc-linters/check-binaries.py                     |  4 +-
 .arc-linters/check-cpp.py                          |  4 +-
 compiler/main/DynFlags.hs                          | 16 +++-
 compiler/main/ErrUtils.hs                          | 97 ++++++++++++++++++++--
 compiler/main/ErrUtils.hs-boot                     |  1 +
 docs/users_guide/using.rst                         |  6 ++
 testsuite/mk/test.mk                               |  1 +
 testsuite/tests/ghci/scripts/T9293.stdout          |  4 +
 testsuite/tests/ghci/scripts/ghci024.stdout        |  1 +
 testsuite/tests/ghci/scripts/ghci057.stdout        |  4 +
 .../warnings/should_fail/CaretDiagnostics1.hs      | 17 ++++
 .../warnings/should_fail/CaretDiagnostics1.stderr  | 72 ++++++++++++++++
 .../warnings/should_fail/CaretDiagnostics2.hs      |  3 +
 .../warnings/should_fail/CaretDiagnostics2.stderr  |  6 ++
 testsuite/tests/warnings/should_fail/all.T         |  2 +
 utils/mkUserGuidePart/Options/Verbosity.hs         |  4 +
 16 files changed, 228 insertions(+), 14 deletions(-)

Diff suppressed because of size. To see it, use:

    git diff-tree --root --patch-with-stat --no-color --find-copies-harder --ignore-space-at-eol --cc 158530a5450b27eb5ae2d75b7895fd1662dde13b