An option to fold every code on startup

[snowphone]

Feature description

Is there any way to do something like set foldlevelstart = 0? I guess foldlevelstart=0 does not work maybe due to internal implementation (Actually it works but whole code is folded on almost every edit).

Describe the solution you'd like

I need something like fold_on_startup = true.

Additional context

No response

[kevinhwang91]

Get and apply folds are asynchronous in ufo, you need to write down your script if you make sure what's provider you need for a buffer.

https://github.com/kevinhwang91/nvim-ufo/blob/0cd49e045553369e5e236d5ac1159ceca373b550/doc/example.lua#L105-L117

    local function applyFoldsAndThenCloseAllFolds(bufnr, providerName)
        require('async')(function()
            bufnr = bufnr or vim.api.nvim_get_current_buf()
            -- make sure buffer is attached
            require('ufo').attach(bufnr)
            -- getFolds return Promise if providerName == 'lsp'
            local ranges = await(require('ufo').getFolds(bufnr, providerName))
            local ok = require('ufo').applyFolds(bufnr, ranges)
            if ok then
                require('ufo').closeAllFolds()
            end
        end)
    end

    vim.api.nvim_create_autocmd('BufRead', {
        pattern = '*',
        callback = function(e)
            applyFoldsAndThenCloseAllFolds(e.buf, 'lsp')
        end
    })

[snowphone]

I put your script to my init.lua but it doesn't work. It throws 'UfoFallbackException'. Do you have any ideas why it happens?

[kevinhwang91]

Your buffer doesn't support lsp, need catch error.

local function applyFoldsAndThenCloseAllFolds(bufnr, providerName)
    require('async')(function()
        bufnr = bufnr or vim.api.nvim_get_current_buf()
        -- make sure buffer is attached
        require('ufo').attach(bufnr)
        -- getFolds return Promise if providerName == 'lsp'
        local ok, ranges = pcall(await, require('ufo').getFolds(bufnr, providerName))
        if ok and ranges then
            ok = require('ufo').applyFolds(bufnr, ranges)
            if ok then
                require('ufo').closeAllFolds()
            end
        end
    end)
end

[snowphone]

Well, as you said the exception is caught but code is not folded still. Did I miss something? Or what should I do to support lsp in my buffer? FYI, I use neovim 0.7.2 stable, coc-nvim, and your plugin.

p.s. it works on lua files (coc-sumneko-lua) but does not work on python (coc-pyright).

[kevinhwang91]

but code is not folded still.

if not ok then getFolds(bufnr, 'indent')

pyright doesn't support foldingrange, check out echo CocAction('hasProvider', 'foldingRange')

[snowphone]

Yeah, as you mentioned, pyright does not support foldingRange feature. So, there's no way to do it without an aid of foldingRange?

[kevinhwang91]

Yes, you can bypass lsp, and use treesitter and indent instead directly for python. getFolds(bufnr, 'lsp') return a promise object that means you can feel the new buffer redraw when the lines become folded. treesitter and indent are sync.

[snowphone]

Thanks a lot! It clearly works :)

For future readers, I just replaced applyFoldsAndThenCloseAllFolds(e.buf, 'lsp') with applyFoldsAndThenCloseAllFolds(e.buf, 'treesitter').

Get and apply folds are asynchronous in ufo, you need to write down your script if you make sure what's provider you need for a buffer.

https://github.com/kevinhwang91/nvim-ufo/blob/0cd49e045553369e5e236d5ac1159ceca373b550/doc/example.lua#L105-L117

    local function applyFoldsAndThenCloseAllFolds(bufnr, providerName)
        require('async')(function()
            bufnr = bufnr or vim.api.nvim_get_current_buf()
            -- make sure buffer is attached
            require('ufo').attach(bufnr)
            -- getFolds return Promise if providerName == 'lsp'
            local ranges = await(require('ufo').getFolds(bufnr, providerName))
            local ok = require('ufo').applyFolds(bufnr, ranges)
            if ok then
                require('ufo').closeAllFolds()
            end
        end)
    end

    vim.api.nvim_create_autocmd('BufRead', {
        pattern = '*',
        callback = function(e)
            applyFoldsAndThenCloseAllFolds(e.buf, 'lsp')
        end
    })

[kevinhwang91]

TBH, I'm not a fan of treesitter. indent for python is enough. The perf is lsp > indent > treesitter.

[mBaratta96]

Hello, tried to follow this issue, but still getting:

Error executing vim.schedule lua callback: UnhandledPromiseRejection with the reason:
...ck/packer/start/nvim-ufo/lua/ufo/provider/treesitter.lua:109: UfoFallbackException

This happens each time I open a new file. Here's my config:

vim.o.foldcolumn = "0" -- '0' is not bad
vim.o.foldlevel = 99   -- Using ufo provider need a large value, feel free to decrease the value
vim.o.foldlevelstart = 99
vim.o.foldenable = true

-- Using ufo provider need remap `zR` and `zM`. If Neovim is 0.6.1, remap yourself
vim.keymap.set("n", "zO", require("ufo").openAllFolds)
vim.keymap.set("n", "zC", require("ufo").closeAllFolds)

require("ufo").setup({
    provider_selector = function(bufnr, filetype, buftype)
        return { "treesitter", "indent" }
    end,
})

local function applyFoldsAndThenCloseAllFolds(bufnr, providerName)
    require("async")(function()
        bufnr = bufnr or vim.api.nvim_get_current_buf()
        -- make sure buffer is attached
        require("ufo").attach(bufnr)
        -- getFolds return Promise if providerName == 'lsp'
        local ranges = await(require("ufo").getFolds(bufnr, providerName))
        local ok = require("ufo").applyFolds(bufnr, ranges)
        if ok then
            require("ufo").closeAllFolds()
        end
    end)
end

vim.api.nvim_create_autocmd("BufRead", {
    pattern = "*",
    callback = function(e)
        applyFoldsAndThenCloseAllFolds(e.buf, "treesitter")
    end,
})

[kevinhwang91]

Read example.lua by yourself.

[mBaratta96]

Managed to figure this out, I switched to lsp and added a specific if else condition with indent fallback:

local function applyFoldsAndThenCloseAllFolds(bufnr, providerName)
    require("async")(function()
        bufnr = bufnr or vim.api.nvim_get_current_buf()
        -- make sure buffer is attached
        require("ufo").attach(bufnr)
        -- getFolds return Promise if providerName == 'lsp'
        local ok, ranges = pcall(await, require("ufo").getFolds(bufnr, providerName))
        if ok and ranges then
            ok = require("ufo").applyFolds(bufnr, ranges)
            if ok then
                require("ufo").closeAllFolds()
            end
        else
            local ranges = await(require("ufo").getFolds(bufnr, "indent"))
            local ok = require("ufo").applyFolds(bufnr, ranges)
            if ok then
                require("ufo").closeAllFolds()
            end
        end
    end)
end

vim.api.nvim_create_autocmd("BufRead", {
    pattern = "*",
    callback = function(e)
        applyFoldsAndThenCloseAllFolds(e.buf, "lsp")
    end,
})