1 files changed, 169 insertions, 2 deletions
diff --git a/test/functional/lua/command_line_completion_spec.lua b/test/functional/lua/command_line_completion_spec.lua
index 2ba432133b..f8786a45bb 100644
--- a/test/functional/lua/command_line_completion_spec.lua
+++ b/test/functional/lua/command_line_completion_spec.lua
@@ -5,12 +5,14 @@ local clear = n.clear
 local eq = t.eq
 local exec_lua = n.exec_lua
 
+--- @return { [1]: string[], [2]: integer }
 local get_completions = function(input, env)
-  return exec_lua('return {vim._expand_pat(...)}', input, env)
+  return exec_lua('return { vim._expand_pat(...) }', input, env)
 end
 
+--- @return { [1]: string[], [2]: integer }
 local get_compl_parts = function(parts)
-  return exec_lua('return {vim._expand_pat_get_parts(...)}', parts)
+  return exec_lua('return { vim._expand_pat_get_parts(...) }', parts)
 end
 
 before_each(clear)
@@ -123,6 +125,171 @@ describe('nlua_expand_pat', function()
     )
   end)
 
+  describe('should complete vim.fn', function()
+    it('correctly works for simple completion', function()
+      local actual = get_completions('vim.fn.did')
+      local expected = {
+        { 'did_filetype' },
+        #'vim.fn.',
+      }
+      eq(expected, actual)
+    end)
+    it('should not suggest items with #', function()
+      exec_lua [[
+        -- ensure remote#host#... functions exist
+        vim.cmd [=[
+          runtime! autoload/remote/host.vim
+        ]=]
+        -- make a dummy call to ensure vim.fn contains an entry: remote#host#...
+        vim.fn['remote#host#IsRunning']('python3')
+      ]]
+      local actual = get_completions('vim.fn.remo')
+      local expected = {
+        { 'remove' }, -- there should be no completion "remote#host#..."
+        #'vim.fn.',
+      }
+      eq(expected, actual)
+    end)
+  end)
+
+  describe('should complete for variable accessors for', function()
+    it('vim.v', function()
+      local actual = get_completions('vim.v.t_')
+      local expected = {
+        { 't_blob', 't_bool', 't_dict', 't_float', 't_func', 't_list', 't_number', 't_string' },
+        #'vim.v.',
+      }
+      eq(expected, actual)
+    end)
+
+    it('vim.g', function()
+      exec_lua [[
+        vim.cmd [=[
+          let g:nlua_foo = 'completion'
+          let g:nlua_foo_bar = 'completion'
+          let g:nlua_foo#bar = 'nocompletion'  " should be excluded from lua completion
+        ]=]
+      ]]
+      local actual = get_completions('vim.g.nlua')
+      local expected = {
+        { 'nlua_foo', 'nlua_foo_bar' },
+        #'vim.g.',
+      }
+      eq(expected, actual)
+    end)
+
+    it('vim.b', function()
+      exec_lua [[
+        vim.b.nlua_foo_buf = 'bar'
+        vim.b.some_other_vars = 'bar'
+      ]]
+      local actual = get_completions('vim.b.nlua')
+      local expected = {
+        { 'nlua_foo_buf' },
+        #'vim.b.',
+      }
+      eq(expected, actual)
+    end)
+
+    it('vim.w', function()
+      exec_lua [[
+        vim.w.nlua_win_var = 42
+      ]]
+      local actual = get_completions('vim.w.nlua')
+      local expected = {
+        { 'nlua_win_var' },
+        #'vim.w.',
+      }
+      eq(expected, actual)
+    end)
+
+    it('vim.t', function()
+      exec_lua [[
+        vim.t.nlua_tab_var = 42
+      ]]
+      local actual = get_completions('vim.t.')
+      local expected = {
+        { 'nlua_tab_var' },
+        #'vim.t.',
+      }
+      eq(expected, actual)
+    end)
+  end)
+
+  describe('should complete for option accessors for', function()
+    -- for { vim.o, vim.go, vim.opt, vim.opt_local, vim.opt_global }
+    local test_opt = function(accessor)
+      do
+        local actual = get_completions(accessor .. '.file')
+        local expected = {
+          'fileencoding',
+          'fileencodings',
+          'fileformat',
+          'fileformats',
+          'fileignorecase',
+          'filetype',
+        }
+        eq({ expected, #accessor + 1 }, actual, accessor .. '.file')
+      end
+      do
+        local actual = get_completions(accessor .. '.winh')
+        local expected = {
+          'winheight',
+          'winhighlight',
+        }
+        eq({ expected, #accessor + 1 }, actual, accessor .. '.winh')
+      end
+    end
+
+    test_opt('vim.o')
+    test_opt('vim.go')
+    test_opt('vim.opt')
+    test_opt('vim.opt_local')
+    test_opt('vim.opt_global')
+
+    it('vim.o, suggesting all the known options', function()
+      local completions = get_completions('vim.o.')[1] ---@type string[]
+      eq(
+        exec_lua [[
+        return vim.tbl_count(vim.api.nvim_get_all_options_info())
+      ]],
+        #completions
+      )
+    end)
+
+    it('vim.bo', function()
+      do
+        local actual = get_completions('vim.bo.file')
+        local compls = {
+          -- should contain buffer options only
+          'fileencoding',
+          'fileformat',
+          'filetype',
+        }
+        eq({ compls, #'vim.bo.' }, actual)
+      end
+      do
+        local actual = get_completions('vim.bo.winh')
+        local compls = {}
+        eq({ compls, #'vim.bo.' }, actual)
+      end
+    end)
+
+    it('vim.wo', function()
+      do
+        local actual = get_completions('vim.wo.file')
+        local compls = {}
+        eq({ compls, #'vim.wo.' }, actual)
+      end
+      do
+        local actual = get_completions('vim.wo.winh')
+        -- should contain window options only
+        local compls = { 'winhighlight' }
+        eq({ compls, #'vim.wo.' }, actual)
+      end
+    end)
+  end)
+
   it('should return everything if the input is of length 0', function()
     eq({ { 'other', 'vim' }, 0 }, get_completions('', { vim = true, other = true }))
   end)