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/api/vim_spec.lua

@@ -366,7 +366,6 @@ describe('API', function()
 
     it('displays messages when opts.output=false', function()
       local screen = Screen.new(40, 8)
-      screen:attach()
       api.nvim_exec2("echo 'hello'", { output = false })
       screen:expect {
         grid = [[
@@ -379,7 +378,6 @@ describe('API', function()
 
     it("doesn't display messages when output=true", function()
       local screen = Screen.new(40, 6)
-      screen:attach()
       api.nvim_exec2("echo 'hello'", { output = true })
       screen:expect {
         grid = [[
@@ -1278,7 +1276,6 @@ describe('API', function()
     end)
     it('pasting with empty last chunk in Cmdline mode', function()
       local screen = Screen.new(20, 4)
-      screen:attach()
       feed(':')
       api.nvim_paste('Foo', true, 1)
       api.nvim_paste('', true, 3)
@@ -1290,7 +1287,6 @@ describe('API', function()
     end)
     it('pasting text with control characters in Cmdline mode', function()
       local screen = Screen.new(20, 4)
-      screen:attach()
       feed(':')
       api.nvim_paste('normal! \023\022\006\027', true, -1)
       screen:expect([[
@@ -1675,7 +1671,6 @@ describe('API', function()
       eq({ 1, 5 }, api.nvim_win_get_cursor(0))
 
       local screen = Screen.new(60, 3)
-      screen:attach()
       eq(1, eval('v:hlsearch'))
       screen:expect {
         grid = [[
@@ -2130,7 +2125,6 @@ describe('API', function()
 
     it('does not complete ("interrupt") `d` #3732', function()
       local screen = Screen.new(20, 4)
-      screen:attach()
       command('set listchars=eol:$')
       command('set list')
       feed('ia<cr>b<cr>c<cr><Esc>kkk')
@@ -2391,7 +2385,6 @@ describe('API', function()
 
     before_each(function()
       screen = Screen.new(40, 8)
-      screen:attach()
     end)
 
     it('prints long messages correctly #20534', function()
@@ -2461,7 +2454,6 @@ describe('API', function()
 
     before_each(function()
       screen = Screen.new(40, 8)
-      screen:attach()
     end)
 
     it('can show one line', function()
@@ -2543,7 +2535,6 @@ describe('API', function()
 
     before_each(function()
       screen = Screen.new(40, 8)
-      screen:attach()
     end)
 
     it('shows only one return prompt after all lines are shown', function()
@@ -3100,8 +3091,7 @@ describe('API', function()
       eq({}, api.nvim_list_uis())
     end)
     it('returns attached UIs', function()
-      local screen = Screen.new(20, 4)
-      screen:attach({ override = true })
+      local screen = Screen.new(20, 4, { override = true })
       local expected = {
         {
           chan = 1,
@@ -3129,8 +3119,7 @@ describe('API', function()
       eq(expected, api.nvim_list_uis())
 
       screen:detach()
-      screen = Screen.new(44, 99)
-      screen:attach({ rgb = false })
+      screen = Screen.new(44, 99, { rgb = false }) -- luacheck: ignore
       expected[1].rgb = false
       expected[1].override = false
       expected[1].width = 44
@@ -3165,7 +3154,6 @@ describe('API', function()
       eq(1, api.nvim_get_current_buf())
 
       local screen = Screen.new(20, 4)
-      screen:attach()
       api.nvim_buf_set_lines(2, 0, -1, true, { 'some text' })
       api.nvim_set_current_buf(2)
       screen:expect(
@@ -3229,7 +3217,6 @@ describe('API', function()
       eq(1, api.nvim_get_current_buf())
 
       local screen = Screen.new(20, 4)
-      screen:attach()
 
       --
       -- Editing a scratch-buffer does NOT change its properties.
@@ -3591,7 +3578,6 @@ describe('API', function()
 
     before_each(function()
       screen = Screen.new(40, 8)
-      screen:attach()
       command('highlight Statement gui=bold guifg=Brown')
       command('highlight Special guifg=SlateBlue')
     end)
@@ -3654,7 +3640,6 @@ describe('API', function()
 
     before_each(function()
       screen = Screen.new(100, 35)
-      screen:attach()
       screen:add_extra_attr_ids {
         [100] = { background = tonumber('0xffff40'), bg_indexed = true },
         [101] = {
@@ -3933,7 +3918,6 @@ describe('API', function()
       command('set readonly')
       eq({ str = '[RO]', width = 4 }, api.nvim_eval_statusline('%r', { maxwidth = 5 }))
       local screen = Screen.new(80, 24)
-      screen:attach()
       command('set showcmd')
       feed('1234')
       screen:expect({ any = '1234' })
@@ -4591,7 +4575,6 @@ describe('API', function()
     end)
     it('does not interfere with printing line in Ex mode #19400', function()
       local screen = Screen.new(60, 7)
-      screen:attach()
       insert([[
         foo
         bar]])
@@ -5048,7 +5031,6 @@ describe('API', function()
 
     it("doesn't display messages when output=true", function()
       local screen = Screen.new(40, 6)
-      screen:attach()
       api.nvim_cmd({ cmd = 'echo', args = { [['hello']] } }, { output = true })
       screen:expect {
         grid = [[
@@ -5131,7 +5113,6 @@ describe('API', function()
 
   it('nvim__redraw', function()
     local screen = Screen.new(60, 5)
-    screen:attach()
     eq('at least one action required', pcall_err(api.nvim__redraw, {}))
     eq('at least one action required', pcall_err(api.nvim__redraw, { buf = 0 }))
     eq('at least one action required', pcall_err(api.nvim__redraw, { win = 0 }))