neovim/test/functional/lua/command_line_completion_spec.lua

local helpers = require('test.functional.helpers')(after_each)

local clear = helpers.clear
local eq = helpers.eq
local exec_lua = helpers.exec_lua

local get_completions = function(input, env)
  return exec_lua("return {vim._expand_pat(...)}", '^' .. input, env)
end

local get_compl_parts = function(parts)
  return exec_lua("return {vim._expand_pat_get_parts(...)}", parts)
end

before_each(clear)

describe('nlua_expand_pat', function()
  it('should complete exact matches', function()
    eq({{'exact'}, 0}, get_completions('exact', { exact = true }))
  end)

  it('should return empty table when nothing matches', function()
    eq({{}, 0}, get_completions('foo', { bar = true }))
  end)

  it('should return nice completions with function call prefix', function()
    eq({{'FOO'}, 6}, get_completions('print(F', { FOO = true, bawr = true }))
  end)

  it('should return keys for nested dictionaries', function()
    eq(
      {{
        'nvim_buf_set_lines',
        'nvim_buf_set_option'
       }, 8
      },
      get_completions('vim.api.nvim_buf_', {
        vim = {
          api = {
            nvim_buf_set_lines = true,
            nvim_buf_set_option = true,
            nvim_win_doesnt_match = true,
          },
          other_key = true,
        }
      })
    )
  end)

  it('it should work with colons', function()
    eq(
      {{
        'bawr',
        'baz',
       }, 8
      },
      get_completions('MyClass:b', {
        MyClass = {
          baz = true,
          bawr = true,
          foo = false,
        }
      })
    )
  end)

  it('should return keys for string reffed dictionaries', function()
    eq(
      {{
        'nvim_buf_set_lines',
        'nvim_buf_set_option'
       }, 11
      },
      get_completions('vim["api"].nvim_buf_', {
        vim = {
          api = {
            nvim_buf_set_lines = true,
            nvim_buf_set_option = true,
            nvim_win_doesnt_match = true,
          },
          other_key = true,
        }
      })
    )
  end)

  it('should return keys for string reffed dictionaries', function()
    eq(
      {{
        'nvim_buf_set_lines',
        'nvim_buf_set_option'
       }, 21
      },
      get_completions('vim["nested"]["api"].nvim_buf_', {
        vim = {
          nested = {
            api = {
              nvim_buf_set_lines = true,
              nvim_buf_set_option = true,
              nvim_win_doesnt_match = true,
            },
          },
          other_key = true,
        }
      })
    )
  end)

  it('should be able to interpolate globals', function()
    eq(
      {{
        'nvim_buf_set_lines',
        'nvim_buf_set_option'
       }, 12
      },
      get_completions('vim[MY_VAR].nvim_buf_', {
        MY_VAR = "api",
        vim = {
          api = {
            nvim_buf_set_lines = true,
            nvim_buf_set_option = true,
            nvim_win_doesnt_match = true,
          },
          other_key = true,
        }
      })
    )
  end)

  it('should return everything if the input is of length 0', function()
    eq({{"other", "vim"}, 0}, get_completions('', { vim = true, other = true }))
  end)

  describe('get_parts', function()
    it('should return an empty list for no separators', function()
      eq({{}, 1}, get_compl_parts("vim"))
    end)

    it('just the first item before a period', function()
      eq({{"vim"}, 5}, get_compl_parts("vim.ap"))
    end)

    it('should return multiple parts just for period', function()
      eq({{"vim", "api"}, 9}, get_compl_parts("vim.api.nvim_buf"))
    end)

    it('should be OK with colons', function()
      eq({{"vim", "api"}, 9}, get_compl_parts("vim:api.nvim_buf"))
    end)

    it('should work for just one string ref', function()
      eq({{"vim", "api"}, 12}, get_compl_parts("vim['api'].nvim_buf"))
    end)

    it('should work for just one string ref, with double quote', function()
      eq({{"vim", "api"}, 12}, get_compl_parts('vim["api"].nvim_buf'))
    end)

    it('should allows back-to-back string ref', function()
      eq({{"vim", "nested", "api"}, 22}, get_compl_parts('vim["nested"]["api"].nvim_buf'))
    end)

    it('should allows back-to-back string ref with spaces before and after', function()
      eq({{"vim", "nested", "api"}, 25}, get_compl_parts('vim[ "nested"  ]["api"].nvim_buf'))
    end)

    it('should allow VAR style loolup', function()
      eq({{"vim", {"NESTED"}, "api"}, 20}, get_compl_parts('vim[NESTED]["api"].nvim_buf'))
    end)
  end)
end)