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

dot_vim/plugged/vimtex/test/test-completion-packages/Makefile

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+.PHONY: test
+
+MYVIM ?= nvim --clean --headless
+
+INMAKE := 1
+export INMAKE
+
+test:
+	@$(MYVIM) -u test.vim

dot_vim/plugged/vimtex/test/test-completion-packages/main.tex

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+\documentclass{minimal}
+\begin{document}
+
+\end{document}

dot_vim/plugged/vimtex/test/test-completion-packages/test.vim

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+set nocompatible
+let &rtp = '../..,' . &rtp
+filetype plugin on
+
+nnoremap q :qall!<cr>
+
+silent edit main.tex
+
+if empty($INMAKE) | finish | endif
+
+let s:candidates = vimtex#test#completion('\usepackage{', 'cleve')
+call assert_equal(s:candidates[0].word, 'cleveref')
+
+let s:candidates = vimtex#test#completion('\RequirePackage{', 'am')
+call assert_true(len(s:candidates) >= 1)
+
+let s:candidates = vimtex#test#completion('\PassOptionsToPackage{option}{', 'am')
+call assert_true(len(s:candidates) >= 1)
+
+call vimtex#test#finished()