feat(normal): lines textobject "il", "al" #39845

`al` to select the whole buffer linewise.
`il` to select the current line without surrounding whitespace.

test/functional/editor/textobject_spec.lua

@@ -0,0 +1,102 @@
+local t = require('test.testutil')
+local n = require('test.functional.testnvim')()
+
+local api = n.api
+local clear = n.clear
+local command = n.command
+local eq = t.eq
+local eval = n.eval
+local feed = n.feed
+local fn = n.fn
+
+local function set_lines(lines)
+  api.nvim_buf_set_lines(0, 0, -1, true, lines)
+end
+
+local function get_lines()
+  return api.nvim_buf_get_lines(0, 0, -1, true)
+end
+
+local function set_cursor(row, col)
+  api.nvim_win_set_cursor(0, { row, col })
+end
+
+describe('line textobject', function()
+  before_each(clear)
+
+  it('selects the current line without surrounding whitespace', function()
+    set_lines({ 'one', '  two words  ', 'three' })
+    set_cursor(2, 4)
+    feed('yil')
+    eq('two words', fn.getreg('"'))
+
+    set_cursor(2, 4)
+    feed('vily')
+    eq('two words', fn.getreg('"'))
+    eq('v', fn.visualmode())
+
+    set_cursor(2, 4)
+    feed('Vily')
+    eq('two words', fn.getreg('"'))
+    eq('v', fn.visualmode())
+
+    set_cursor(2, 0)
+    feed('0v$ily')
+    eq('two words', fn.getreg('"'))
+
+    set_cursor(1, 0)
+    feed('Vjily')
+    eq('two words', fn.getreg('"'))
+
+    command('set selection=exclusive')
+    set_cursor(2, 4)
+    feed('vily')
+    eq('two words', fn.getreg('"'))
+    command('set selection&')
+
+    set_cursor(2, 4)
+    feed('dil')
+    eq({ 'one', '    ', 'three' }, get_lines())
+
+    set_lines({ '  αβ  ', '  ', 'last' })
+    set_cursor(1, 2)
+    feed('yil')
+    eq('αβ', fn.getreg('"'))
+
+    command('set selection=exclusive')
+    set_cursor(1, 2)
+    feed('vily')
+    eq('αβ', fn.getreg('"'))
+    command('set selection&')
+
+    fn.setreg('"', 'unchanged')
+    set_cursor(2, 0)
+    eq(0, fn.assert_beeps('normal yil'))
+    eq('unchanged', fn.getreg('"'))
+
+    set_cursor(2, 0)
+    eq(0, fn.assert_beeps('normal vily'))
+    eq('unchanged', fn.getreg('"'))
+  end)
+
+  it('selects all lines without moving the cursor for yank', function()
+    set_lines({ '  αβ  ', '  ', 'last' })
+    command('let g:textobj_line_yank_pos = []')
+    command([[autocmd TextYankPost <buffer> ++once let g:textobj_line_yank_pos = getpos('.')]])
+
+    set_cursor(3, 0)
+    feed('yal')
+    eq('  αβ  \n  \nlast\n', fn.getreg('"'))
+    eq({ 0, 3, 1, 0 }, fn.getpos('.'))
+    eq({ 0, 3, 1, 0 }, eval('g:textobj_line_yank_pos'))
+
+    set_cursor(3, 0)
+    feed('valy')
+    eq('  αβ  \n  \nlast\n', fn.getreg('"'))
+    eq('V', fn.visualmode())
+
+    set_cursor(2, 0)
+    feed('dal')
+    eq({ '' }, get_lines())
+  end)
+end)