/usr/share/vim/addons/syntax/snippet.vim is in vim-snipmate 0.87-3.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 | " Syntax highlighting for .snippet files (used for snipMate.vim)
" Hopefully this should make snippets a bit nicer to write!
syn match placeHolder '\${\d\+\(:.\{-}\)\=}' contains=snipCommand
syn match tabStop '\$\d\+'
syn match snipEscape '\\\\\|\\`'
syn match snipCommand '\%(\\\@<!\%(\\\\\)*\)\@<=`.\{-}\%(\\\@<!\%(\\\\\)*\)\@<=`'
hi link placeHolder Special
hi link tabStop Special
hi link snipEscape SpecialChar
hi link snipCommand String
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