Many formatters inserts ^M (\r, CR) at the end of each line on windows.

[jmwielandt]

Before proceeding
If you modified the configuration yourself, check that you tried options such as no_append or ignore_exitcode, and also, if you can, try to run the configuration in your shell.

Shell command and output (optional):

Which configuration? (at least:)
Type (custom or builtin): builtin
Filetype: markdown
Formatter: prettier

Configuration(s) (post all the variants you tried): no variants.

Expected behavior

Formatter respect my LF file on windows.

Actual behaviour

Formatter adds a ^M char at the end of each line.

Additional context
Add any other context about the problem here.

I don't remember which formatter was, but other than prettier on markdown did the same thing.

[jmwielandt]

update: gofmt + goimports do the same, but with null-ls didn't happened

[nmaillet]

Seems like it may be splitting lines via \n and keeping \r's in the lines (supposedly then being passed to stdin as \r\r\n). A workaround I found was to transform the input and trim \r's off the end of the lines, like so:

local formatter_prettierd = function()
    -- Call function to get defaults.
    local defaults = require('formatter.defaults.prettierd')();

    -- Add a transform function.
    defaults.transform = function(text)
        -- text is an array of lines, trim any carriage returns/new lines from the end of each.
        for key,value in pairs(text) do
            text[key] = string.gsub(value, '[\n\r]+$', '');
        end;
        return text;
    end;

    return defaults;
end;

require('formatter').setup({
    filetype = {
        javascript = { formatter_prettierd },
        javascriptreact = { formatter_prettierd },
        typescript = { formatter_prettierd  },
        typescriptreact = { formatter_prettierd },
        markdown = { formatter_prettierd },
    },
});

local group = vim.api.nvim_create_augroup('BufWritePreFormatter', {});
vim.api.nvim_create_autocmd('BufWritePre', {
    command = 'FormatWrite',
    group = group,
    pattern = { '*.js', '*.jsx', '*.ts', '*.tsx', '*.md' },
});

[igor-ribeiro]

@nmaillet Does it format for you using BufWritePre? For me most of the time I have to save twice to actually format.

[nmaillet]

@igor-ribeiro No actually, I did have issues with that. I believe I had moved everything over to BufWritePost. I've switched over to using conform.nvim though, so I can't tell you exactly how I had it working before switching.