[commit: ghc] master: Fix parsing of And chains in BoolFormula (4ad3620)

[git at git.haskell.org]

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

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/4ad36206285a84bfc3c9f7d41c55bba83bfdffef/ghc

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commit 4ad36206285a84bfc3c9f7d41c55bba83bfdffef
Author: Dmitry Ivanov <ethercrow at gmail.com>
Date:   Thu Feb 23 18:02:23 2017 -0500

    Fix parsing of And chains in BoolFormula
    
    Parse `foo, bar, baz` into `And [foo, bar, baz]`
    instead of `And [foo, And [bar, baz]]`.
    
    Fixes #11024.
    
    Test Plan: read and think
    
    Reviewers: austin, bgamari, mpickering
    
    Reviewed By: bgamari, mpickering
    
    Subscribers: ezyang, thomie, alanz
    
    Differential Revision: https://phabricator.haskell.org/D3139


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4ad36206285a84bfc3c9f7d41c55bba83bfdffef
 compiler/parser/Parser.y | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/compiler/parser/Parser.y b/compiler/parser/Parser.y
index 175cfbb..fcc3707 100644
--- a/compiler/parser/Parser.y
+++ b/compiler/parser/Parser.y
@@ -2959,9 +2959,13 @@ name_boolformula :: { LBooleanFormula (Located RdrName) }
                               >> return (sLL $1 $> (Or [$1,$3])) }
 
 name_boolformula_and :: { LBooleanFormula (Located RdrName) }
-        : name_boolformula_atom                             { $1 }
-        | name_boolformula_atom ',' name_boolformula_and
-                  {% aa $1 (AnnComma,$2) >> return (sLL $1 $> (And [$1,$3])) }
+        : name_boolformula_and_list
+                  { sLL (head $1) (last $1) (And ($1)) }
+
+name_boolformula_and_list :: { [LBooleanFormula (Located RdrName)] }
+        : name_boolformula_atom                               { [$1] }
+        | name_boolformula_atom ',' name_boolformula_and_list
+            {% aa $1 (AnnComma, $2) >> return ($1 : $3) }
 
 name_boolformula_atom :: { LBooleanFormula (Located RdrName) }
         : '(' name_boolformula ')'  {% ams (sLL $1 $> (Parens $2)) [mop $1,mcp $3] }