Snacks Breakpoint Picker

[joshuaprimrose]

I'm using nvim-dap to list breakpoints in a picker. Not terribly familiar with Lua or the Neovim API so any suggestions would be helpful. Feel free to take whatever you want.

local M = {}

local trim = function(s)
   return (s:gsub("^%s*(.-)%s*$", "%1"))
end

local get_items = function()
    local bps = require('dap.breakpoints').get()

    local items = {}

    for bufnr, breakpoints in pairs(bps) do
        local filename = vim.api.nvim_buf_get_name(bufnr)

        for _, item in ipairs(breakpoints) do
            local text = vim.api.nvim_buf_get_lines(bufnr, item.line - 1, item.line, false)[1]

            table.insert(items, {
                bufnr = bufnr,
                file = filename,
                line_num = item.line,
                pos = {item.line, 0},
                text = trim(text),
            })
        end
    end

    return items
end

local treesitter_parse_text = function(bufnr, line_num)
    local line = vim.api.nvim_buf_get_lines(bufnr, line_num - 1, line_num, false)[1] or ""

    if line == "" then
        return { { line, 'SnacksPickerDir' } }
    end

    local ok = pcall(vim.treesitter.get_parser, bufnr)
    if not ok then
        local filetype = vim.api.nvim_get_option_value('filetype', { buf = bufnr })
        vim.notify(
            'No Treesitter parser installed for filetype ' .. filetype .. ' defaulting to plain text',
            vim.log.levels.ERROR
        )
        return {
            {
                trim(line),
                '@text',
            },
        }
    end

    local segments = {}
    local seg_start = 0
    local seg_hl = nil
    local len = #line

    for col = 0, len - 1 do
        local captures = vim.treesitter.get_captures_at_pos(bufnr, line_num - 1, col)

        local hl = nil

        if #captures > 0 then
            -- last entry = most specific/highest-priority capture at this column
            local cap = captures[#captures]
            hl = "@" .. cap.capture .. "." .. cap.lang
        end

        if hl ~= seg_hl then
            if col > seg_start then
                local text = line:sub(seg_start + 1, col)

                if seg_start == 0 and text:match("^%s*$") ~= nil then
                    text = ''
                end

                segments[#segments + 1] = seg_hl and { text, seg_hl } or { text }
            end

            seg_start = col
            seg_hl = hl
        end
    end

    -- flush final segment
    local text = line:sub(seg_start + 1, len)
    segments[#segments + 1] = seg_hl and { text, seg_hl } or { text }

    return segments
end

function M.show()
    Snacks.picker({
        confirm = function(picker, item)
            picker:close()

            if vim.api.nvim_buf_is_loaded(item.bufnr) then
                vim.api.nvim_set_current_buf(item.bufnr)
                local winid = vim.fn.bufwinid(item.bufnr)
                vim.api.nvim_win_set_cursor(winid, {item.line_num, 0})
            else
                vim.notify('Unable to locate buffer: ' .. item.bufnr, vim.log.levels.ERROR)
            end
        end,
        format = function(item, _)
            local filename = vim.fn.fnamemodify(item.file, ":t")
            local prefix = string.format("%s:%d ", filename, item.line_num)

            local segments = {
                {
                    ' ',
                    'DapBreakpoint',
                },
                {
                    prefix,
                    'SnacksPickerFile'
                }
            }

            vim.list_extend(segments, treesitter_parse_text(item.bufnr, item.line_num))

            return segments
        end,
        items = get_items(),
        layout = {
            preset = 'default',
        },
        preview = 'file',
        title = 'Breakpoint Picker',
    })
end

return M

[drowning-cat]

Sorry, I didn't look at the code carefully enough, and I'm a bit sleepy.

1. Use vim.trim.
2. Do you need to override the confirm action? Try confirm="jump" or confirm="drop".
3. Do you need treesitter_parse_text? I'd prefer Snacks.picker.highlight.get_highlights.
4. You can also use finder = function() end instead of items(), but it's not necessary.
5. You can follow the noice.nvim approach for defining picker sources: 1 and 2.
6. You could also move the discussion to "Show and Tell".

[joshuaprimrose]

@drowning-cat Thanks for the tips very much appreciated! Apologies, didn't see the Show and Tell.