fix(tests): needing two calls to setup a screen is cringe

Before calling "attach" a screen object is just a dummy container for
(row, col) values whose purpose is to be sent as part of the "attach"
function call anyway.

Just create the screen in an attached state directly. Keep the complete
(row, col, options) config together. It is still completely valid to
later detach and re-attach as needed, including to another session.

test/functional/vimscript/api_functions_spec.lua

@@ -129,8 +129,6 @@ describe('eval-API', function()
   end)
 
   it('use buffer numbers and windows ids as handles', function()
-    local screen = Screen.new(40, 8)
-    screen:attach()
     local bnr = eval("bufnr('')")
     local bhnd = eval('nvim_get_current_buf()')
     local wid = eval('win_getid()')
@@ -192,7 +190,6 @@ describe('eval-API', function()
 
   it('are highlighted by vim.vim syntax file', function()
     local screen = Screen.new(40, 8)
-    screen:attach()
 
     command('set ft=vim')
     command('set rtp^=build/runtime/')

test/functional/vimscript/eval_spec.lua

@@ -189,7 +189,6 @@ describe('uncaught exception', function()
 
   it('multiline exception remains multiline #25350', function()
     local screen = Screen.new(80, 11)
-    screen:attach()
     exec_lua([[
       function _G.Oops()
         error("oops")
@@ -230,8 +229,7 @@ describe('listing functions using :function', function()
   end)
 
   it('does not crash if another function is deleted while listing', function()
-    local screen = Screen.new(80, 24)
-    screen:attach()
+    local _ = Screen.new(80, 24)
     matches(
       'Vim%(function%):E454: Function list was modified$',
       pcall_err(
@@ -264,8 +262,7 @@ describe('listing functions using :function', function()
   end)
 
   it('does not crash if the same function is deleted while listing', function()
-    local screen = Screen.new(80, 24)
-    screen:attach()
+    local _ = Screen.new(80, 24)
     matches(
       'Vim%(function%):E454: Function list was modified$',
       pcall_err(

test/functional/vimscript/execute_spec.lua

@@ -114,7 +114,6 @@ describe('execute()', function()
 
   it('does not corrupt the command display #5422', function()
     local screen = Screen.new(70, 7)
-    screen:attach()
     feed(':echo execute("hi ErrorMsg")<CR>')
     screen:expect(
       [[
@@ -136,7 +135,6 @@ describe('execute()', function()
 
   it('places cursor correctly #6035', function()
     local screen = Screen.new(40, 6)
-    screen:attach()
     source([=[
       " test 1: non-silenced output goes as usual
       function! Test1()
@@ -263,7 +261,6 @@ describe('execute()', function()
   describe('{silent} argument', function()
     it('captures & displays output for ""', function()
       local screen = Screen.new(40, 5)
-      screen:attach()
       command('let g:mes = execute("echon 42", "")')
       screen:expect([[
       ^                                        |
@@ -287,7 +284,6 @@ describe('execute()', function()
 
     it('captures but does not display output for "silent"', function()
       local screen = Screen.new(40, 5)
-      screen:attach()
       command('let g:mes = execute("echon 42")')
       screen:expect([[
       ^                                        |

test/functional/vimscript/has_spec.lua

@@ -4,6 +4,7 @@ local Screen = require('test.functional.ui.screen')
 
 local clear = n.clear
 local connect = n.connect
+local get_session = n.get_session
 local eq = t.eq
 local fn = n.fn
 local is_os = t.is_os
@@ -74,12 +75,12 @@ describe('has()', function()
 
   it('"gui_running"', function()
     eq(0, fn.has('gui_running'))
-    local tui = Screen.new(50, 15)
+    local tui_session = get_session()
     local gui_session = connect(fn.serverstart())
-    local gui = Screen.new(50, 15)
     eq(0, fn.has('gui_running'))
-    tui:attach({ ext_linegrid = true, rgb = true, stdin_tty = true, stdout_tty = true })
-    gui:attach({ ext_multigrid = true, rgb = true }, gui_session)
+    local tui = Screen.new(50, 5, { rgb = true, stdin_tty = true, stdout_tty = true }, tui_session)
+    eq(0, fn.has('gui_running'))
+    local gui = Screen.new(50, 15, { ext_multigrid = true, rgb = true }, gui_session)
     eq(1, fn.has('gui_running'))
     tui:detach()
     eq(1, fn.has('gui_running'))

test/functional/vimscript/input_spec.lua

@@ -17,7 +17,6 @@ local screen
 before_each(function()
   clear()
   screen = Screen.new(25, 5)
-  screen:attach()
   source([[
     hi Test ctermfg=Red guifg=Red term=bold
     function CustomCompl(...)

test/functional/vimscript/match_functions_spec.lua

@@ -174,7 +174,6 @@ describe('matchaddpos()', function()
   end)
   it('works with zero length', function()
     local screen = Screen.new(40, 5)
-    screen:attach()
     fn.setline(1, 'abcdef')
     command('hi PreProc guifg=Red')
     eq(4, fn.matchaddpos('PreProc', { { 1, 2, 0 } }, 3, 4))

test/functional/vimscript/system_spec.lua

@@ -132,7 +132,6 @@ describe('system()', function()
 
     before_each(function()
       screen = Screen.new()
-      screen:attach()
     end)
 
     if is_os('win') then
@@ -430,11 +429,6 @@ describe('systemlist()', function()
 
     before_each(function()
       screen = Screen.new()
-      screen:attach()
-    end)
-
-    after_each(function()
-      screen:detach()
     end)
 
     it('`echo` and waits for its return', function()
@@ -567,7 +561,6 @@ describe('shell :!', function()
 
   it(':{range}! with powershell filter/redirect #16271 #19250', function()
     local screen = Screen.new(500, 8)
-    screen:attach()
     local found = n.set_shell_powershell(true)
     insert([[
       3
@@ -598,7 +591,6 @@ describe('shell :!', function()
 
   it(':{range}! without redirecting to buffer', function()
     local screen = Screen.new(500, 10)
-    screen:attach()
     insert([[
       3
       1

test/functional/vimscript/timer_spec.lua

@@ -108,7 +108,6 @@ describe('timers', function()
 
   it('can invoke redraw in blocking getchar() call', function()
     local screen = Screen.new(40, 6)
-    screen:attach()
 
     api.nvim_buf_set_lines(0, 0, -1, true, { 'ITEM 1', 'ITEM 2' })
     source([[
@@ -225,7 +224,6 @@ describe('timers', function()
 
   it("doesn't mess up the cmdline", function()
     local screen = Screen.new(40, 6)
-    screen:attach()
     source([[
       let g:val = 0
       func! MyHandler(timer)
@@ -263,7 +261,6 @@ describe('timers', function()
 
   it('can be triggered after an empty string <expr> mapping #17257', function()
     local screen = Screen.new(40, 6)
-    screen:attach()
     command([=[imap <expr> <F2> [timer_start(0, { _ -> execute("throw 'x'", "") }), ''][-1]]=])
     feed('i<F2>')
     screen:expect({ any = 'E605: Exception not caught: x' })