Allow specifying arguments to launch DAP.

jrpotter/neovim/lua/init/dap.lua

@@ -1,13 +1,76 @@
 local M = {}
 
+local dap = require('dap')
+local dap_ui = require('dap.ui')
+local dap_ui_widgets = require('dap.ui.widgets')
+
+local function query_launch()
+  local command = vim.fn.input('Executable> ', vim.fn.getcwd() .. '/', 'file')
+  vim.api.nvim_echo({ { '', 'None' } }, false, {})
+
+  local parts = vim.split(command, '%s+', { trimempty = true })
+  if not parts[1] then
+    vim.api.nvim_err_writeln('Invalid command specification.')
+    return
+  end
+
+  return parts[1], {unpack(parts, 2, #parts)}
+end
+
+-- Adaptation of https://github.com/mfussenegger/nvim-dap/blob/e154fdb6d70b3765d71f296e718b29d8b7026a63/lua/dap.lua#L413.
+local function select_config_and_run()
+  local filetype = vim.api.nvim_buf_get_option(0, 'filetype')
+  local configs = dap.configurations[filetype] or {}
+  assert(
+    vim.tbl_islist(configs),
+    string.format(
+      '`dap.configurations.%s` must be a list of configurations, got %s',
+      filetype,
+      vim.inspect(configs)
+    )
+  )
+  if not configs[1] then
+    local msg = 'No configuration found for `%s`. You need to add configs ' ..
+        'to `dap.configurations.%s` (See `:h dap-configuration`)'
+    vim.api.nvim_err_writeln(string.format(msg, filetype, filetype))
+    return
+  end
+
+  local opts = {}
+  opts.filetype = opts.filetype or filetype
+
+  dap_ui.pick_if_many(
+    configs,
+    'Configuration: ',
+    function(c)  -- Label function
+      return c.name
+    end,
+    function(c)  -- Callback
+      if not c then
+        vim.api.nvim_err_writeln('No configuration selected.')
+        return
+      end
+      local copy = vim.deepcopy(c)
+      if copy.request == 'launch' then
+        local program, args = query_launch()
+        copy.program = program
+        copy.args = args
+      end
+      dap.run(copy, opts)
+    end
+  )
+end
+
 local function sidebar_new(widget)
-  return require('dap.ui.widgets').sidebar(widget, { width = 40 }, '')
+  return dap_ui_widgets.sidebar(widget, { width = 40 }, '')
 end
 
 local function sidebar_is_open(sidebar)
   return sidebar.win and vim.api.nvim_win_is_valid(sidebar.win)
 end
 
+-- Setup buffer-local DAP mappings. This function is expected to be called in
+-- a filetype plugin, e.g. `nvim/after/ftplugin/c.lua`.
 function M.buffer_map()
   local function set_nnoremap(key, func)
     vim.keymap.set(
@@ -18,9 +81,6 @@ function M.buffer_map()
     )
   end
 
-  local dap = require('dap')
-  local dap_ui_widgets = require('dap.ui.widgets')
-
   local sidebars = {
     expression = sidebar_new(dap_ui_widgets.expression),
     frames = sidebar_new(dap_ui_widgets.frames),
@@ -50,8 +110,15 @@ function M.buffer_map()
     end
   end
 
-  set_nnoremap('<localleader>', dap.continue)
+  set_nnoremap('<localleader>', select_config_and_run)
   set_nnoremap('b', dap.toggle_breakpoint)
+  set_nnoremap('c', function()
+    if dap.status() == '' then
+      vim.api.nvim_err_writeln('No active session.')
+      return
+    end
+    dap.continue()
+  end)
   set_nnoremap('d', dap.down)
   set_nnoremap('i', dap.step_into)
   set_nnoremap('n', dap.step_over)