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

dot_vim/plugged/vimtex/test/test-completion-bibtex/test_custom_bibs.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
+
+let g:vimtex_bibliography_commands = [
+      \ 'mybibliography',
+      \]
+
+silent edit test_custom_bibs.tex
+
+if empty($INMAKE) | finish | endif
+
+let s:candidates = vimtex#test#completion('\cite*{', '')
+call assert_true(len(s:candidates) > 0)
+
+call vimtex#test#finished()