test: update tests for auto-closing :term buffers

The terminal buffer closes automatically when using `:terminal` and the
command exits without an error. This messes up some tests that expect
the terminal buffer to still be open. We can force the buffer not to
close by passing an argument to `:terminal`. This can be anything, since
the shell-test stub simply prints whatever argument it's given.

test/functional/autocmd/termxx_spec.lua

@@ -103,12 +103,13 @@ describe('autocmd TermClose', function()
 
   it('reports the correct <abuf>', function()
     command('set hidden')
+    command('set shellcmdflag=EXE')
     command('autocmd TermClose * let g:abuf = expand("<abuf>")')
     command('edit foo')
     command('edit bar')
     eq(2, eval('bufnr("%")'))
 
-    command('terminal')
+    command('terminal ls')
     retry(nil, nil, function() eq(3, eval('bufnr("%")')) end)
 
     command('buffer 1')

test/functional/terminal/ex_terminal_spec.lua

@@ -137,23 +137,29 @@ describe(':terminal (with fake shell)', function()
     -- shell-test.c is a fake shell that prints its arguments and exits.
     nvim('set_option_value', 'shell', testprg('shell-test'), {})
     nvim('set_option_value', 'shellcmdflag', 'EXE', {})
+    nvim('set_option_value', 'shellxquote', '', {})
   end)
 
   -- Invokes `:terminal {cmd}` using a fake shell (shell-test.c) which prints
-  -- the {cmd} and exits immediately .
+  -- the {cmd} and exits immediately.
+  -- When no argument is given and the exit code is zero, the terminal buffer
+  -- closes automatically.
   local function terminal_with_fake_shell(cmd)
     feed_command("terminal "..(cmd and cmd or ""))
   end
 
   it('with no argument, acts like termopen()', function()
     skip(is_os('win'))
-    terminal_with_fake_shell()
+    -- Use the EXIT subcommand to end the process with a non-zero exit code to
+    -- prevent the buffer from closing automatically
+    nvim('set_option_value', 'shellcmdflag', 'EXIT', {})
+    terminal_with_fake_shell(1)
     retry(nil, 4 * screen.timeout, function()
     screen:expect([[
-      ^ready $                                           |
-      [Process exited 0]                                |
+      ^                                                  |
+      [Process exited 1]                                |
                                                         |
-      :terminal                                         |
+      :terminal 1                                       |
     ]])
     end)
   end)
@@ -245,12 +251,13 @@ describe(':terminal (with fake shell)', function()
 
   it('works with :find', function()
     skip(is_os('win'))
-    terminal_with_fake_shell()
+    nvim('set_option_value', 'shellcmdflag', 'EXIT', {})
+    terminal_with_fake_shell(1)
     screen:expect([[
-      ^ready $                                           |
-      [Process exited 0]                                |
+      ^                                                  |
+      [Process exited 1]                                |
                                                         |
-      :terminal                                         |
+      :terminal 1                                       |
     ]])
     eq('term://', string.match(eval('bufname("%")'), "^term://"))
     feed([[<C-\><C-N>]])

test/functional/terminal/scrollback_spec.lua

@@ -514,7 +514,9 @@ describe("'scrollback' option", function()
 
     -- _Global_ scrollback=-1 defaults :terminal to 10_000.
     command('setglobal scrollback=-1')
-    command('terminal')
+    -- Pass a command to prevent the terminal buffer from automatically
+    -- closing. The ':' command is just a no-op.
+    command('terminal :')
     eq(10000, meths.get_option_value('scrollback', {}))
 
     -- _Local_ scrollback=-1 in :terminal forces the _maximum_.

test/functional/terminal/tui_spec.lua

@@ -2075,26 +2075,26 @@ describe('TUI FocusGained/FocusLost', function()
   end)
 
   it('in terminal-mode', function()
-    feed_data(':set shell='..testprg('shell-test')..'\n')
+    feed_data(':set shell='..testprg('shell-test')..' shellcmdflag=EXE\n')
     feed_data(':set noshowmode laststatus=0\n')
 
-    feed_data(':terminal\n')
+    feed_data(':terminal zia\n')
     -- Wait for terminal to be ready.
     screen:expect{grid=[[
-      {1:r}eady $                                           |
+      {1:r}eady $ zia                                       |
+                                                        |
       [Process exited 0]                                |
                                                         |
                                                         |
-                                                        |
-      :terminal                                         |
+      :terminal zia                                     |
       {3:-- TERMINAL --}                                    |
     ]]}
 
     feed_data('\027[I')
     screen:expect{grid=[[
-      {1:r}eady $                                           |
-      [Process exited 0]                                |
+      {1:r}eady $ zia                                       |
                                                         |
+      [Process exited 0]                                |
                                                         |
                                                         |
       gained                                            |
@@ -2103,9 +2103,9 @@ describe('TUI FocusGained/FocusLost', function()
 
     feed_data('\027[O')
     screen:expect([[
-      {1:r}eady $                                           |
-      [Process exited 0]                                |
+      {1:r}eady $ zia                                       |
                                                         |
+      [Process exited 0]                                |
                                                         |
                                                         |
       lost                                              |