Commit: Runtime: Add nixInherit matcher in nix.vim syntax

[Christian Brabandt]

Runtime: Add nixInherit matcher in nix.vim syntax

Commit: https://github.com/vim/vim/commit/72904d5fda0a1bc78f4bc9080c158226e6e90d5c
Author: James Fleming <ja...@electronic-quill.net>
Date: Sat Jul 29 12:01:18 2023 +0200

Runtime: Add nixInherit matcher in nix.vim syntax

Perform the lookahead in `nixInheritAttributeScope`, then hand over to a
new region called `nixInheritAttributeSubExpr`, which sets the match
start to one char after the opening bracket to avoid a double-match.

Finally, only do a lookahead to `)` in `nixInheritAttributeSubExpr` (and
thus make sure the region is closed to not get a match of `nixParen`
here) and let `nixInheritAttributeScope` close the bracket.

Signed-off-by: Christian Brabandt <c...@256bit.org>

diff --git a/runtime/syntax/nix.vim b/runtime/syntax/nix.vim
index c07676a4a..671b269c0 100644
--- a/runtime/syntax/nix.vim
+++ b/runtime/syntax/nix.vim
@@ -1,11 +1,12 @@
" Vim syntax file
" Language: Nix
-" Maintainer: James Fleming <ja...@electronic-quill.net>
+" Maintainer: James Fleming <ja...@electronic-quill.net>
+" (Github username: equill)
" Original Author: Daiderd Jordan <dai...@gmail.com>
" Acknowledgement: Based on vim-nix maintained by Daiderd Jordan <dai...@gmail.com>
" https://github.com/LnL7/vim-nix
" License: MIT
-" Last Change: 2022 Dec 06
+" Last Change: 2023 Aug 19

if exists("b:current_syntax")
finish
@@ -68,7 +69,8 @@ syn match nixAttribute "[a-zA-Z_][a-zA-Z0-9_'-]*\ze\%([^a-zA-Z0-9_'.-]\|$\)" con
syn region nixAttributeAssignment start="=" end="\ze;" contained contains=@nixExpr
syn region nixAttributeDefinition start=/\ze[a-zA-Z_"$]/ end=";" contained contains=nixComment,nixAttribute,nixInterpolation,nixSimpleString,nixAttributeDot,nixAttributeAssignment

-syn region nixInheritAttributeScope start="(" end="\ze)" contained contains=@nixExpr
+syn region nixInheritAttributeSubExpr start="("ms=e+1 end="\ze)" contained contains=nixAttributeDot,@nixExpr
+syn region nixInheritAttributeScope start="\ze(" end=")" contained contains=nixInheritAttributeSubExpr
syn region nixAttributeDefinition matchgroup=nixInherit start="\<inherit\>" end=";" contained contains=nixComment,nixInheritAttributeScope,nixAttribute

syn region nixAttributeSet start="{" end="}" contains=nixComment,nixAttributeDefinition