neovim/test/functional/ui/mouse_spec.lua

local helpers = require('test.functional.helpers')
local Screen = require('test.functional.ui.screen')
local clear, feed, nvim = helpers.clear, helpers.feed, helpers.nvim

describe('Mouse input', function()
  local screen, hlgroup_colors

  setup(function()
    hlgroup_colors = {
      Visual = nvim('name_to_color', 'LightGrey'),
    }
  end)

  before_each(function()
    clear()
    nvim('set_option', 'mouse', 'a')
    -- set mouset to very high value to ensure that even in valgrind/travis,
    -- nvim will still pick multiple clicks
    nvim('set_option', 'mouset', 5000)
    screen = Screen.new(25, 5)
    screen:attach()
    screen:set_default_attr_ids({
      [1] = {background = hlgroup_colors.Visual}
    })
    feed('itesting<cr>mouse<cr>support and selection<esc>')
    screen:expect([[
      testing                  |
      mouse                    |
      support and selectio^    |
      ~                        |
                               |
    ]])
  end)

  after_each(function()
    screen:detach()
  end)

  it('left click moves cursor', function()
    feed('<LeftMouse><2,1>')
    screen:expect([[
      testing                  |
      mo^se                    |
      support and selection    |
      ~                        |
                               |
    ]])
    feed('<LeftMouse><0,0>')
    screen:expect([[
      ^esting                  |
      mouse                    |
      support and selection    |
      ~                        |
                               |
    ]])
  end)

  it('left drag changes visual selection', function()
    -- drag events must be preceded by a click
    feed('<LeftMouse><2,1>')
    screen:expect([[
      testing                  |
      mo^se                    |
      support and selection    |
      ~                        |
                               |
    ]])
    feed('<LeftDrag><4,1>')
    screen:expect([[
      testing                  |
      mo{1:us}^                    |
      support and selection    |
      ~                        |
      -- VISUAL --             |
    ]])
    feed('<LeftDrag><2,2>')
    screen:expect([[
      testing                  |
      mo{1:use }                   |
      {1:su}^port and selection    |
      ~                        |
      -- VISUAL --             |
    ]])
    feed('<LeftDrag><0,0>')
    screen:expect([[
      ^{1:esting }                 |
      {1:mou}se                    |
      support and selection    |
      ~                        |
      -- VISUAL --             |
    ]])
  end)

  it('two clicks will select the word and enter VISUAL', function()
    feed('<LeftMouse><2,2><LeftMouse><2,2>')
    screen:expect([[
      testing                  |
      mouse                    |
      {1:suppor}^ and selection    |
      ~                        |
      -- VISUAL --             |
    ]])
  end)

  it('three clicks will select the line and enter VISUAL LINE', function()
    feed('<LeftMouse><2,2><LeftMouse><2,2><LeftMouse><2,2>')
    screen:expect([[
      testing                  |
      mouse                    |
      {1:su}^{1:port and selection }   |
      ~                        |
      -- VISUAL LINE --        |
    ]])
  end)

  it('four clicks will enter VISUAL BLOCK', function()
    feed('<LeftMouse><2,2><LeftMouse><2,2><LeftMouse><2,2><LeftMouse><2,2>')
    screen:expect([[
      testing                  |
      mouse                    |
      su^port and selection    |
      ~                        |
      -- VISUAL BLOCK --       |
    ]])
  end)

  it('right click extends visual selection to the clicked location', function()
    feed('<LeftMouse><0,0>')
    screen:expect([[
      ^esting                  |
      mouse                    |
      support and selection    |
      ~                        |
                               |
    ]])
    feed('<RightMouse><2,2>')
    screen:expect([[
      {1:testing }                 |
      {1:mouse }                   |
      {1:su}^port and selection    |
      ~                        |
      -- VISUAL --             |
    ]])
  end)

  it('ctrl + left click will search for a tag', function()
    feed('<C-LeftMouse><0,0>')
    screen:expect([[
      E433: No tags file       |
      E426: tag not found: test|
      ing                      |
      Press ENTER or type comma|
      nd to continue^          |
    ]])
    feed('<cr>')
  end)
end)