Automagically formatting on save, with Neovim and Language Server Protocol (LSP)
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Moving to Neovim, one of the really key benefits of the move was the native Language Server Protocol (LSP) support.
After being quite used to the way that I could get my Java projects to autoformat on build, I did, however, want a little more from Neovim's configuration.
The Neovim docs actually highlight this:
autocmd BufWritePre <buffer> lua vim.lsp.buf.format()
" or
autocmd BufWritePre * lua vim.lsp.buf.format()
Or if you're using the Lua configuration:
vim.cmd [[autocmd BufWritePre <buffer> lua vim.lsp.buf.format()]]
-- or
vim.cmd [[autocmd BufWritePre * lua vim.lsp.buf.format()]]
Or if you want to write Lua, but haven't yet fully migrated to a Lua-only configuration, you'll want the following:
lua <<EOF
vim.cmd [[autocmd BufWritePre * lua vim.lsp.buf.format()]]
EOF
Then, every time you save your file(s), they'll attempt to format using the registered LSP, and if none exist, it'll be a no-op.