vim-patch:8.2.0866: not enough tests for buffer writing

Problem:    Not enough tests for buffer writing.
Solution:   Add more tests. Use CheckRunVimInTerminal in more places.
            (Yegappan Lakshmanan, closes vim/vim#6167)

https://github.com/vim/vim/commit/494e9069cb32620f7688a7cb128a3feff827639e

12 files changed, 147 insertions, 42 deletions

diff --git a/src/nvim/testdir/test_arglist.vim b/src/nvim/testdir/test_arglist.vim
index 443a217143..cae71e10f3 100644
--- a/src/nvim/testdir/test_arglist.vim
+++ b/src/nvim/testdir/test_arglist.vim
@@ -1,5 +1,6 @@
 " Test argument list commands
 
+source check.vim
 source shared.vim
 source term_util.vim
 
@@ -552,9 +553,7 @@ endfunc
 
 " Test for quitting Vim with unedited files in the argument list
 func Test_quit_with_arglist()
-  if !CanRunVimInTerminal()
-    throw 'Skipped: cannot run vim in terminal'
-  endif
+  CheckRunVimInTerminal
   let buf = RunVimInTerminal('', {'rows': 6})
   call term_sendkeys(buf, ":set nomore\n")
   call term_sendkeys(buf, ":args a b c\n")
diff --git a/src/nvim/testdir/test_match.vim b/src/nvim/testdir/test_match.vim
index 352493de9c..29d087bc23 100644
--- a/src/nvim/testdir/test_match.vim
+++ b/src/nvim/testdir/test_match.vim
@@ -343,9 +343,7 @@ func Test_matchdelete_error()
 endfunc
 
 func Test_matchclear_other_window()
-  if !CanRunVimInTerminal()
-    throw 'Skipped: cannot make screendumps'
-  endif
+  CheckRunVimInTerminal
   let buf = OtherWindowCommon()
   call term_sendkeys(buf, ":call clearmatches(winid)\<CR>")
   call VerifyScreenDump(buf, 'Test_matchclear_1', {})
@@ -355,9 +353,7 @@ func Test_matchclear_other_window()
 endfunc
 
 func Test_matchadd_other_window()
-  if !CanRunVimInTerminal()
-    throw 'Skipped: cannot make screendumps'
-  endif
+  CheckRunVimInTerminal
   let buf = OtherWindowCommon()
   call term_sendkeys(buf, ":call matchadd('Search', 'Hello', 1, -1, #{window: winid})\<CR>")
   call term_sendkeys(buf, ":\<CR>")
diff --git a/src/nvim/testdir/test_search.vim b/src/nvim/testdir/test_search.vim
index d79910fbc1..cb35868b47 100644
--- a/src/nvim/testdir/test_search.vim
+++ b/src/nvim/testdir/test_search.vim
@@ -897,9 +897,7 @@ func Test_incsearch_cmdline_modifier()
 endfunc
 
 func Test_incsearch_scrolling()
-  if !CanRunVimInTerminal()
-    throw 'Skipped: cannot make screendumps'
-  endif
+  CheckRunVimInTerminal
   call assert_equal(0, &scrolloff)
   call writefile([
 	\ 'let dots = repeat(".", 120)',
diff --git a/src/nvim/testdir/test_signals.vim b/src/nvim/testdir/test_signals.vim
index 31b76919e1..c291c68e0d 100644
--- a/src/nvim/testdir/test_signals.vim
+++ b/src/nvim/testdir/test_signals.vim
@@ -81,6 +81,7 @@ endfunc
 
 " Test signal INT. Handler sets got_int. It should be like typing CTRL-C.
 func Test_signal_INT()
+  CheckRunVimInTerminal
   if !HasSignal('INT')
     throw 'Skipped: INT signal not supported'
   endif
@@ -92,9 +93,6 @@ func Test_signal_INT()
     throw 'Skipped: cannot test signal INT with valgrind'
   endif
 
-  if !CanRunVimInTerminal()
-    throw 'Skipped: cannot run vim in terminal'
-  endif
   let buf = RunVimInTerminal('', {'rows': 6})
   let pid_vim = term_getjob(buf)->job_info().process
 
@@ -121,9 +119,7 @@ func Test_deadly_signal_TERM()
   if !HasSignal('TERM')
     throw 'Skipped: TERM signal not supported'
   endif
-  if !CanRunVimInTerminal()
-    throw 'Skipped: cannot run vim in terminal'
-  endif
+  CheckRunVimInTerminal
   let cmd = GetVimCommand()
   if cmd =~ 'valgrind'
     throw 'Skipped: cannot test signal TERM with valgrind'
diff --git a/src/nvim/testdir/test_signs.vim b/src/nvim/testdir/test_signs.vim
index ff9ba3d8ed..aa43477c5f 100644
--- a/src/nvim/testdir/test_signs.vim
+++ b/src/nvim/testdir/test_signs.vim
@@ -1741,9 +1741,7 @@ endfunc
 
 " Test for correct cursor position after the sign column appears or disappears.
 func Test_sign_cursor_position()
-  if !CanRunVimInTerminal()
-    throw 'Skipped: cannot make screendumps'
-  endif
+  CheckRunVimInTerminal
 
   let lines =<< trim END
 	call setline(1, [repeat('x', 75), 'mmmm', 'yyyy'])
diff --git a/src/nvim/testdir/test_startup.vim b/src/nvim/testdir/test_startup.vim
index b8aad1bc46..30bbd355df 100644
--- a/src/nvim/testdir/test_startup.vim
+++ b/src/nvim/testdir/test_startup.vim
@@ -809,9 +809,7 @@ func Test_issue_3969()
 endfunc
 
 func Test_start_with_tabs()
-  if !CanRunVimInTerminal()
-    return
-  endif
+  CheckRunVimInTerminal
 
   let buf = RunVimInTerminal('-p a b c', {})
   call VerifyScreenDump(buf, 'Test_start_with_tabs', {})
@@ -968,9 +966,7 @@ endfunc
 
 " Test for specifying a non-existing vimrc file using "-u"
 func Test_missing_vimrc()
-  if !CanRunVimInTerminal()
-    throw 'Skipped: cannot run vim in terminal'
-  endif
+  CheckRunVimInTerminal
   let after =<< trim [CODE]
     call assert_match('^E282:', v:errmsg)
     call writefile(v:errors, 'Xtestout')
diff --git a/src/nvim/testdir/test_startup_utf8.vim b/src/nvim/testdir/test_startup_utf8.vim
index bb4304396e..2ee6ecc41d 100644
--- a/src/nvim/testdir/test_startup_utf8.vim
+++ b/src/nvim/testdir/test_startup_utf8.vim
@@ -63,9 +63,7 @@ func Test_read_fifo_utf8()
 endfunc
 
 func Test_detect_ambiwidth()
-  if !CanRunVimInTerminal()
-    throw 'Skipped: cannot run Vim in a terminal window'
-  endif
+  CheckRunVimInTerminal
 
   " Use the title termcap entries to output the escape sequence.
   call writefile([
diff --git a/src/nvim/testdir/test_syntax.vim b/src/nvim/testdir/test_syntax.vim
index 9903b48dbe..29ebe141f7 100644
--- a/src/nvim/testdir/test_syntax.vim
+++ b/src/nvim/testdir/test_syntax.vim
@@ -631,9 +631,7 @@ endfunc
 
 " Check highlighting for a small piece of C code with a screen dump.
 func Test_syntax_c()
-  if !CanRunVimInTerminal()
-    throw 'Skipped: cannot make screendumps'
-  endif
+  CheckRunVimInTerminal
   call writefile([
 	\ '/* comment line at the top */',
 	\ 'int main(int argc, char **argv) { // another comment',
diff --git a/src/nvim/testdir/test_tabpage.vim b/src/nvim/testdir/test_tabpage.vim
index 4ada48d56c..b97aa409d8 100644
--- a/src/nvim/testdir/test_tabpage.vim
+++ b/src/nvim/testdir/test_tabpage.vim
@@ -591,9 +591,7 @@ func Test_tabs()
 endfunc
 
 func Test_tabpage_cmdheight()
-  if !CanRunVimInTerminal()
-    throw 'Skipped: cannot make screendumps'
-  endif
+  CheckRunVimInTerminal
   call writefile([
         \ 'set laststatus=2',
         \ 'set cmdheight=2',
diff --git a/src/nvim/testdir/test_timers.vim b/src/nvim/testdir/test_timers.vim
index 3a6abb3968..f94ee6c9f3 100644
--- a/src/nvim/testdir/test_timers.vim
+++ b/src/nvim/testdir/test_timers.vim
@@ -304,9 +304,7 @@ func Test_timer_ex_mode()
 endfunc
 
 func Test_timer_restore_count()
-  if !CanRunVimInTerminal()
-    throw 'Skipped: cannot run Vim in a terminal window'
-  endif
+  CheckRunVimInTerminal
   " Check that v:count is saved and restored, not changed by a timer.
   call writefile([
         \ 'nnoremap <expr><silent> L v:count ? v:count . "l" : "l"',
diff --git a/src/nvim/testdir/test_vimscript.vim b/src/nvim/testdir/test_vimscript.vim
index bd60dcb707..3a6baaf1f0 100644
--- a/src/nvim/testdir/test_vimscript.vim
+++ b/src/nvim/testdir/test_vimscript.vim
@@ -1707,9 +1707,7 @@ endfunc
 
 " Test for deep nesting of if/for/while/try statements              {{{1
 func Test_deep_nest()
-  if !CanRunVimInTerminal()
-    throw 'Skipped: cannot run vim in terminal'
-  endif
+  CheckRunVimInTerminal
 
   let lines =<< trim [SCRIPT]
     " Deep nesting of if ... endif
diff --git a/src/nvim/testdir/test_writefile.vim b/src/nvim/testdir/test_writefile.vim
index 7dfcaaedeb..59214d1aab 100644
--- a/src/nvim/testdir/test_writefile.vim
+++ b/src/nvim/testdir/test_writefile.vim
@@ -267,6 +267,138 @@ func Test_write_errors()
   " call writefile(v:_null_blob, 'Xfile')
   " call assert_false(filereadable('Xfile'))
   call assert_fails('call writefile([], "")', 'E482:')
+
+  " very long file name
+  let long_fname = repeat('n', 5000)
+  call assert_fails('exe "w " .. long_fname', 'E75:')
+  call assert_fails('call writefile([], long_fname)', 'E482:')
+endfunc
+
+" Test for writing to a file which is modified after Vim read it
+func Test_write_file_mtime()
+  CheckEnglish
+  CheckRunVimInTerminal
+
+  " First read the file into a buffer
+  call writefile(["Line1", "Line2"], 'Xfile')
+  let old_ftime = getftime('Xfile')
+  let buf = RunVimInTerminal('Xfile', #{rows : 10})
+  call term_wait(buf)
+  call term_sendkeys(buf, ":set noswapfile\<CR>")
+  call term_wait(buf)
+
+  " Modify the file directly.  Make sure the file modification time is
+  " different. Note that on Linux/Unix, the file is considered modified
+  " outside, only if the difference is 2 seconds or more
+  sleep 1
+  call writefile(["Line3", "Line4"], 'Xfile')
+  let new_ftime = getftime('Xfile')
+  while new_ftime - old_ftime < 2
+    sleep 100m
+    call writefile(["Line3", "Line4"], 'Xfile')
+    let new_ftime = getftime('Xfile')
+  endwhile
+
+  " Try to overwrite the file and check for the prompt
+  call term_sendkeys(buf, ":w\<CR>")
+  call term_wait(buf)
+  call WaitForAssert({-> assert_equal("WARNING: The file has been changed since reading it!!!", term_getline(buf, 9))})
+  call assert_equal("Do you really want to write to it (y/n)?",
+        \ term_getline(buf, 10))
+  call term_sendkeys(buf, "n\<CR>")
+  call term_wait(buf)
+  call assert_equal(new_ftime, getftime('Xfile'))
+  call term_sendkeys(buf, ":w\<CR>")
+  call term_wait(buf)
+  call term_sendkeys(buf, "y\<CR>")
+  call term_wait(buf)
+  call WaitForAssert({-> assert_equal('Line2', readfile('Xfile')[1])})
+
+  " clean up
+  call StopVimInTerminal(buf)
+  call delete('Xfile')
+endfunc
+
+" Test for an autocmd unloading a buffer during a write command
+func Test_write_autocmd_unloadbuf_lockmark()
+  augroup WriteTest
+    autocmd BufWritePre Xfile enew | write
+  augroup END
+  e Xfile
+  call assert_fails('lockmarks write', 'E203:')
+  augroup WriteTest
+    au!
+  augroup END
+  augroup! WriteTest
+endfunc
+
+" Test for writing a buffer with 'acwrite' but without autocmds
+func Test_write_acwrite_error()
+  new Xfile
+  call setline(1, ['line1', 'line2', 'line3'])
+  set buftype=acwrite
+  call assert_fails('write', 'E676:')
+  call assert_fails('1,2write!', 'E676:')
+  call assert_fails('w >>', 'E676:')
+  close!
+endfunc
+
+" Test for adding and removing lines from an autocmd when writing a buffer
+func Test_write_autocmd_add_remove_lines()
+  new Xfile
+  call setline(1, ['aaa', 'bbb', 'ccc', 'ddd'])
+
+  " Autocmd deleting lines from the file when writing a partial file
+  augroup WriteTest2
+    au!
+    autocmd FileWritePre Xfile 1,2d
+  augroup END
+  call assert_fails('2,3w!', 'E204:')
+
+  " Autocmd adding lines to a file when writing a partial file
+  augroup WriteTest2
+    au!
+    autocmd FileWritePre Xfile call append(0, ['xxx', 'yyy'])
+  augroup END
+  %d
+  call setline(1, ['aaa', 'bbb', 'ccc', 'ddd'])
+  1,2w!
+  call assert_equal(['xxx', 'yyy', 'aaa', 'bbb'], readfile('Xfile'))
+
+  " Autocmd deleting lines from the file when writing the whole file
+  augroup WriteTest2
+    au!
+    autocmd BufWritePre Xfile 1,2d
+  augroup END
+  %d
+  call setline(1, ['aaa', 'bbb', 'ccc', 'ddd'])
+  w
+  call assert_equal(['ccc', 'ddd'], readfile('Xfile'))
+
+  augroup WriteTest2
+    au!
+  augroup END
+  augroup! WriteTest2
+
+  close!
+  call delete('Xfile')
+endfunc
+
+" Test for writing to a readonly file
+func Test_write_readonly()
+  " In Cirrus-CI, the freebsd tests are run under a root account. So this test
+  " doesn't fail.
+  CheckNotBSD
+  call writefile([], 'Xfile')
+  call setfperm('Xfile', "r--------")
+  edit Xfile
+  set noreadonly
+  call assert_fails('write', 'E505:')
+  let save_cpo = &cpo
+  set cpo+=W
+  call assert_fails('write!', 'E504:')
+  let &cpo = save_cpo
+  call delete('Xfile')
 endfunc
 
 " Test for writing a file using invalid file encoding