I broke up with neovim....vim is my best friend now

dot_vim/plugged/vimtex/test/test-completion-bibtex/test_backend.vim

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+set nocompatible
+let &rtp = '../..,' . &rtp
+filetype plugin on
+
+nnoremap q :qall!<cr>
+
+let g:vimtex_cache_root = '.'
+let g:vimtex_cache_persistent = 0
+
+if !empty($BACKEND)
+  let g:vimtex_parser_bib_backend = $BACKEND
+endif
+
+silent edit test_backend.tex
+
+if empty($INMAKE) | finish | endif
+
+" Simplify test on basic systems
+if empty(vimtex#kpsewhich#find('biblatex-examples.bib'))
+  let s:candidates = vimtex#test#completion('\cite{', '')
+  call assert_true(len(s:candidates) >= 1)
+  call vimtex#test#finished()
+  quit!
+endif
+
+let s:candidates = vimtex#test#completion('\cite{', '')
+call assert_equal(94, len(s:candidates))
+
+let s:candidates = vimtex#test#completion('\citet{', '.*ocal')
+call assert_equal(2, len(s:candidates))
+
+let s:candidates = vimtex#test#completion(
+      \ '\parencite[see][5--10]{', 'Arist.*1929')
+call assert_equal(1, len(s:candidates))
+call assert_equal('aristotle:physics', s:candidates[0].word)
+
+let g:vimtex_complete_bib.simple = 1
+let s:candidates = vimtex#test#completion('\textcite[5--10]{', 'aristotle:p')
+call assert_equal(2, len(s:candidates))
+call assert_equal('aristotle:physics', s:candidates[0].word)
+
+call vimtex#test#finished()