[commit: ghc] ghc-8.4: Improve treatment of sectioned holes (da83722)

[git at git.haskell.org]

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

On branch  : ghc-8.4
Link       : http://ghc.haskell.org/trac/ghc/changeset/da83722c503a2f032bf21b386b8021c0794d4176/ghc

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

commit da83722c503a2f032bf21b386b8021c0794d4176
Author: Ryan Scott <ryan.gl.scott at gmail.com>
Date:   Wed Dec 20 19:25:53 2017 -0500

    Improve treatment of sectioned holes
    
    Previously, GHC was pretty-printing left-section holes
    incorrectly and not parsing right-sectioned holes at all. This patch
    fixes both problems.
    
    Test Plan: make test TEST=T14590
    
    Reviewers: bgamari, simonpj
    
    Reviewed By: simonpj
    
    Subscribers: simonpj, rwbarton, thomie, mpickering, carter
    
    GHC Trac Issues: #14590
    
    Differential Revision: https://phabricator.haskell.org/D4273
    
    (cherry picked from commit 4d41e9212d1fdf109f2d0174d204644446f5874c)


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da83722c503a2f032bf21b386b8021c0794d4176
 compiler/hsSyn/HsExpr.hs                           |   4 +
 compiler/parser/Parser.y                           |  10 +-
 testsuite/tests/typecheck/should_compile/T14590.hs |   7 +
 .../tests/typecheck/should_compile/T14590.stderr   | 264 +++++++++++++++++++++
 testsuite/tests/typecheck/should_compile/all.T     |   1 +
 5 files changed, 283 insertions(+), 3 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 da83722c503a2f032bf21b386b8021c0794d4176