--- a/src/main.c
+++ b/src/main.c
@@ -1966,7 +1966,7 @@ parse_command_name(mparm_T *parmp)
 #endif
     }
 
-    // Checking for "ex" here may catch some weir names, such as "vimex" or
+    // Checking for "ex" here may catch some weird names, such as "vimex" or
     // "viewex", we assume the user knows that.
     if (STRNICMP(initstr, "ex", 2) == 0)
     {

--- a/src/testdir/check.vim
+++ b/src/testdir/check.vim
@@ -133,3 +133,13 @@ func CheckNotRoot()
     throw 'Skipped: cannot run test as root'
   endif
 endfunc
+
+" Command to check that the current language is English
+command CheckEnglish call CheckEnglish()
+func CheckEnglish()
+  if v:lang != "C" && v:lang !~ '^[Ee]n'
+      throw 'Skipped: only works in English language environment'
+  endif
+endfunc
+
+" vim: shiftwidth=2 sts=2 expandtab

--- a/src/testdir/shared.vim
+++ b/src/testdir/shared.vim
@@ -337,3 +337,5 @@ func IsRoot()
   endif
   return v:false
 endfunc
+
+" vim: shiftwidth=2 sts=2 expandtab

--- a/src/testdir/term_util.vim
+++ b/src/testdir/term_util.vim
@@ -82,6 +82,8 @@ func RunVimInTerminal(arguments, options
     let cols = term_getsize(buf)[1]
   endif
 
+  call term_wait(buf)
+
   " Wait for "All" or "Top" of the ruler to be shown in the last line or in
   " the status line of the last window. This can be quite slow (e.g. when
   " using valgrind).
@@ -113,3 +115,5 @@ func StopVimInTerminal(buf)
   call WaitForAssert({-> assert_equal("finished", term_getstatus(a:buf))})
   only!
 endfunc
+
+" vim: shiftwidth=2 sts=2 expandtab

--- a/src/testdir/test_clientserver.vim
+++ b/src/testdir/test_clientserver.vim
@@ -6,11 +6,7 @@ CheckFeature clientserver
 
 source shared.vim
 
-func Test_client_server()
-  let cmd = GetVimCommand()
-  if cmd == ''
-    return
-  endif
+func Check_X11_Connection()
   if has('x11')
     if empty($DISPLAY)
       throw 'Skipped: $DISPLAY is not set'
@@ -19,11 +15,19 @@ func Test_client_server()
       call remote_send('xxx', '')
     catch
       if v:exception =~ 'E240:'
-	throw 'Skipped: no connection to the X server'
+        throw 'Skipped: no connection to the X server'
       endif
       " ignore other errors
     endtry
   endif
+endfunc
+
+func Test_client_server()
+  let cmd = GetVimCommand()
+  if cmd == ''
+    return
+  endif
+  call Check_X11_Connection()
 
   let name = 'XVIMTEST'
   let cmd .= ' --servername ' . name
@@ -72,6 +76,10 @@ func Test_client_server()
   endif
   let g:testvar = 'myself'
   call assert_equal('myself', remote_expr(v:servername, 'testvar'))
+  call remote_send(v:servername, ":let g:testvar2 = 75\<CR>")
+  call feedkeys('', 'x')
+  call assert_equal(75, g:testvar2)
+  call assert_fails('let v = remote_expr(v:servername, "/2")', 'E449:')
 
   call remote_send(name, ":call server2client(expand('<client>'), 'got it')\<CR>", 'g:myserverid')
   call assert_equal('got it', g:myserverid->remote_read(2))
@@ -92,6 +100,55 @@ func Test_client_server()
   call assert_equal('another', g:peek_result)
   call assert_equal('another', remote_read(g:myserverid, 2))
 
+  if !has('gui_running')
+    " In GUI vim, the following tests display a dialog box
+
+    let cmd = GetVimProg() .. ' --servername ' .. name
+
+    " Run a separate instance to send a command to the server
+    call remote_expr(name, 'execute("only")')
+    call system(cmd .. ' --remote-send ":new Xfile<CR>"')
+    call assert_equal('2', remote_expr(name, 'winnr("$")'))
+    call assert_equal('Xfile', remote_expr(name, 'winbufnr(1)->bufname()'))
+    call remote_expr(name, 'execute("only")')
+
+    " Invoke a remote-expr. On MS-Windows, the returned value has a carriage
+    " return.
+    let l = system(cmd .. ' --remote-expr "2 + 2"')
+    call assert_equal(['4'], split(l, "\n"))
+
+    " Edit multiple files using --remote
+    call system(cmd .. ' --remote Xfile1 Xfile2 Xfile3')
+    call assert_equal("Xfile1\nXfile2\nXfile3\n", remote_expr(name, 'argv()'))
+    eval name->remote_send(":%bw!\<CR>")
+
+    " Edit files in separate tab pages
+    call system(cmd .. ' --remote-tab Xfile1 Xfile2 Xfile3')
+    call assert_equal('3', remote_expr(name, 'tabpagenr("$")'))
+    call assert_equal('Xfile2', remote_expr(name, 'bufname(tabpagebuflist(2)[0])'))
+    eval name->remote_send(":%bw!\<CR>")
+
+    " Edit a file using --remote-wait
+    eval name->remote_send(":source $VIMRUNTIME/plugin/rrhelper.vim\<CR>")
+    call system(cmd .. ' --remote-wait +enew Xfile1')
+    call assert_equal("Xfile1", remote_expr(name, 'bufname("#")'))
+    eval name->remote_send(":%bw!\<CR>")
+
+    " Edit files using --remote-tab-wait
+    call system(cmd .. ' --remote-tabwait +tabonly\|enew Xfile1 Xfile2')
+    call assert_equal('1', remote_expr(name, 'tabpagenr("$")'))
+    eval name->remote_send(":%bw!\<CR>")
+
+    " Error cases
+    if v:lang == "C" || v:lang =~ '^[Ee]n'
+      let l = split(system(cmd .. ' --remote +pwd'), "\n")
+      call assert_equal("Argument missing after: \"+pwd\"", l[1])
+    endif
+    let l = system(cmd .. ' --remote-expr "abcd"')
+    call assert_match('^E449: ', l)
+  endif
+
+  eval name->remote_send(":%bw!\<CR>")
   eval name->remote_send(":qa!\<CR>")
   try
     call WaitForAssert({-> assert_equal("dead", job_status(job))})
@@ -102,8 +159,8 @@ func Test_client_server()
     endif
   endtry
 
-  call assert_fails("let x=remote_peek([])", 'E730:')
-  call assert_fails("let x=remote_read('vim10')", 'E277:')
+  call assert_fails("let x = remote_peek([])", 'E730:')
+  call assert_fails("let x = remote_read('vim10')", 'E277:')
 endfunc
 
 " Uncomment this line to get a debugging log

--- a/src/testdir/test_ex_mode.vim
+++ b/src/testdir/test_ex_mode.vim
@@ -146,9 +146,7 @@ endfunc
 " In Ex-mode, backslashes at the end of a command should be halved.
 func Test_Ex_echo_backslash()
   " This test works only when the language is English
-  if v:lang != "C" && v:lang !~ '^[Ee]n'
-    return
-  endif
+  CheckEnglish
   let bsl = '\\\\'
   let bsl2 = '\\\'
   call assert_fails('call feedkeys("Qecho " .. bsl .. "\nvisual\n", "xt")',

--- a/src/testdir/test_expand.vim
+++ b/src/testdir/test_expand.vim
@@ -84,6 +84,15 @@ func Test_expandcmd()
   let $FOO="blue\tsky"
   call setline(1, "$FOO")
   call assert_equal("grep pat blue\tsky", expandcmd('grep pat <cfile>'))
+
+  " Test for expression expansion `=
+  let $FOO= "blue"
+  call assert_equal("blue sky", expandcmd("`=$FOO .. ' sky'`"))
+
+  " Test for env variable with spaces
+  let $FOO= "foo bar baz"
+  call assert_equal("e foo bar baz", expandcmd("e $FOO"))
+
   unlet $FOO
   close!
 endfunc

--- a/src/testdir/test_functions.vim
+++ b/src/testdir/test_functions.vim
@@ -659,6 +659,7 @@ func Save_mode()
   return ''
 endfunc
 
+" Test for the mode() function
 func Test_mode()
   new
   call append(0, ["Blue Ball Black", "Brown Band Bowl", ""])
@@ -782,6 +783,8 @@ func Test_mode()
   call assert_equal('c-c', g:current_modes)
   call feedkeys("gQecho \<C-R>=Save_mode()\<CR>\<CR>vi\<CR>", 'xt')
   call assert_equal('c-cv', g:current_modes)
+  call feedkeys("Qcall Save_mode()\<CR>vi\<CR>", 'xt')
+  call assert_equal('c-ce', g:current_modes)
   " How to test Ex mode?
 
   bwipe!
@@ -1284,6 +1287,19 @@ func Test_inputlist()
   call feedkeys(":let c = inputlist(['Select color:', '1. red', '2. green', '3. blue'])\<cr>3\<cr>", 'tx')
   call assert_equal(3, c)
 
+  " Use backspace to delete characters in the prompt
+  call feedkeys(":let c = inputlist(['Select color:', '1. red', '2. green', '3. blue'])\<cr>1\<BS>3\<BS>2\<cr>", 'tx')
+  call assert_equal(2, c)
+
+  " Use mouse to make a selection
+  call test_setmouse(&lines - 3, 2)
+  call feedkeys(":let c = inputlist(['Select color:', '1. red', '2. green', '3. blue'])\<cr>\<LeftMouse>", 'tx')
+  call assert_equal(1, c)
+  " Mouse click outside of the list
+  call test_setmouse(&lines - 6, 2)
+  call feedkeys(":let c = inputlist(['Select color:', '1. red', '2. green', '3. blue'])\<cr>\<LeftMouse>", 'tx')
+  call assert_equal(-2, c)
+
   call assert_fails('call inputlist("")', 'E686:')
 endfunc
 

--- a/src/testdir/test_options.vim
+++ b/src/testdir/test_options.vim
@@ -1,6 +1,7 @@
 " Test for options
 
 source check.vim
+source view_util.vim
 
 func Test_whichwrap()
   set whichwrap=b,s
@@ -707,4 +708,12 @@ func Test_rightleftcmd()
   set rightleft&
 endfunc
 
+" Test for the "debug" option
+func Test_debug_option()
+  set debug=beep
+  exe "normal \<C-c>"
+  call assert_equal('Beep!', Screenline(&lines))
+  set debug&
+endfunc
+
 " vim: shiftwidth=2 sts=2 expandtab

--- a/src/testdir/test_startup.vim
+++ b/src/testdir/test_startup.vim
@@ -2,6 +2,7 @@
 
 source shared.vim
 source screendump.vim
+source term_util.vim
 source check.vim
 
 " Check that loading startup.vim works.
@@ -10,6 +11,9 @@ func Test_startup_script()
   source $VIMRUNTIME/defaults.vim
 
   call assert_equal(0, &compatible)
+  " Restore some options, so that the following tests doesn't break
+  set nomore
+  set noshowmode
 endfunc
 
 " Verify the order in which plugins are loaded:
@@ -322,6 +326,10 @@ func Test_q_arg()
 	\             lines)
   endif
 
+  " Test with a non-existing error file (exits with value 3)
+  let out = system(GetVimCommand() .. ' -q xyz.err')
+  call assert_equal(3, v:shell_error)
+
   call delete('Xtestout')
   call delete('Xerrors')
 endfunc
@@ -687,3 +695,268 @@ func Test_v_argv()
   call assert_true(idx > 2)
   call assert_equal(['arg1', '--cmd', 'echo v:argv', '--cmd', 'q'']'], list[idx:])
 endfunc
+
+" Test for the "-r" recovery mode option
+func Test_r_arg()
+  " Can't catch the output of gvim.
+  CheckNotGui
+  CheckUnix
+  CheckEnglish
+  let cmd = GetVimCommand()
+  " There can be swap files anywhere, only check for the headers.
+  let expected =<< trim END
+    Swap files found:.*
+    In current directory:.*
+    In directory \~/tmp:.*
+    In directory /var/tmp:.*
+    In directory /tmp:.*
+  END
+  call assert_match(join(expected, ""), system(cmd .. " -r")->substitute("[\r\n]\\+", '', ''))
+endfunc
+
+" Test for the '-t' option to jump to a tag
+func Test_t_arg()
+  let before =<< trim [CODE]
+    set tags=Xtags
+  [CODE]
+  let after =<< trim [CODE]
+    let s = bufname('') .. ':L' .. line('.') .. 'C' .. col('.')
+    call writefile([s], "Xtestout")
+    qall
+  [CODE]
+
+  call writefile(["!_TAG_FILE_ENCODING\tutf-8\t//",
+        \ "first\tXfile1\t/^    \\zsfirst$/",
+        \ "second\tXfile1\t/^    \\zssecond$/",
+        \ "third\tXfile1\t/^    \\zsthird$/"],
+        \ 'Xtags')
+  call writefile(['    first', '    second', '    third'], 'Xfile1')
+
+  if RunVim(before, after, '-t second')
+    call assert_equal(['Xfile1:L2C5'], readfile('Xtestout'))
+    call delete('Xtestout')
+  endif
+
+  call delete('Xtags')
+  call delete('Xfile1')
+endfunc
+
+" Test for entering the insert mode on startup
+func Test_start_insertmode()
+  let before =<< trim [CODE]
+    set insertmode
+  [CODE]
+  let after =<< trim [CODE]
+    call writefile(['insertmode=' .. &insertmode], 'Xtestout')
+    qall
+  [CODE]
+  if RunVim(before, after, '')
+    call assert_equal(['insertmode=1'], readfile('Xtestout'))
+    call delete('Xtestout')
+  endif
+endfunc
+
+" Test for enabling the binary mode on startup
+func Test_b_arg()
+  let after =<< trim [CODE]
+    call writefile(['binary=' .. &binary], 'Xtestout')
+    qall
+  [CODE]
+  if RunVim([], after, '-b')
+    call assert_equal(['binary=1'], readfile('Xtestout'))
+    call delete('Xtestout')
+  endif
+endfunc
+
+" Test for enabling the lisp mode on startup
+func Test_l_arg()
+  let after =<< trim [CODE]
+    let s = 'lisp=' .. &lisp .. ', showmatch=' .. &showmatch
+    call writefile([s], 'Xtestout')
+    qall
+  [CODE]
+  if RunVim([], after, '-l')
+    call assert_equal(['lisp=1, showmatch=1'], readfile('Xtestout'))
+    call delete('Xtestout')
+  endif
+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
+  let after =<< trim [CODE]
+    call assert_match('^E282:', v:errmsg)
+    call writefile(v:errors, 'Xtestout')
+  [CODE]
+  call writefile(after, 'Xafter')
+
+  let cmd = GetVimCommandCleanTerm() . ' -u Xvimrc_missing -S Xafter'
+  let buf = term_start(cmd, {'term_rows' : 10})
+  call WaitForAssert({-> assert_equal("running", term_getstatus(buf))})
+  call term_wait(buf)
+  call term_sendkeys(buf, "\n:")
+  call term_wait(buf)
+  call WaitForAssert({-> assert_match(':', term_getline(buf, 10))})
+  call StopVimInTerminal(buf)
+  call assert_equal([], readfile('Xtestout'))
+  call delete('Xafter')
+  call delete('Xtestout')
+endfunc
+
+" Test for using the $VIMINIT environment variable
+func Test_VIMINIT()
+  let after =<< trim [CODE]
+    call assert_equal(1, exists('viminit_found'))
+    call assert_equal('yes', viminit_found)
+    call writefile(v:errors, 'Xtestout')
+    qall
+  [CODE]
+  call writefile(after, 'Xafter')
+  let cmd = GetVimProg() . ' --not-a-term -S Xafter --cmd "set enc=utf8"'
+  call setenv('VIMINIT', 'let viminit_found="yes"')
+  exe "silent !" . cmd
+  call assert_equal([], readfile('Xtestout'))
+  call delete('Xtestout')
+  call delete('Xafter')
+endfunc
+
+" Test for using the $EXINIT environment variable
+func Test_EXINIT()
+  let after =<< trim [CODE]
+    call assert_equal(1, exists('exinit_found'))
+    call assert_equal('yes', exinit_found)
+    call writefile(v:errors, 'Xtestout')
+    qall
+  [CODE]
+  call writefile(after, 'Xafter')
+  let cmd = GetVimProg() . ' --not-a-term -S Xafter --cmd "set enc=utf8"'
+  call setenv('EXINIT', 'let exinit_found="yes"')
+  exe "silent !" . cmd
+  call assert_equal([], readfile('Xtestout'))
+  call delete('Xtestout')
+  call delete('Xafter')
+endfunc
+
+" Test for using the 'exrc' option
+func Test_exrc()
+  let after =<< trim [CODE]
+    call assert_equal(1, &exrc)
+    call assert_equal(1, &secure)
+    call assert_equal(37, exrc_found)
+    call writefile(v:errors, 'Xtestout')
+    qall
+  [CODE]
+  call mkdir('Xdir')
+  call writefile(['let exrc_found=37'], 'Xdir/.exrc')
+  call writefile(after, 'Xdir/Xafter')
+  let cmd = GetVimProg() . ' --not-a-term -S Xafter --cmd "cd Xdir" --cmd "set enc=utf8 exrc secure"'
+  exe "silent !" . cmd
+  call assert_equal([], readfile('Xdir/Xtestout'))
+  call delete('Xdir', 'rf')
+endfunc
+
+" Test for starting Vim with a non-terminal as input/output
+func Test_io_not_a_terminal()
+  " Can't catch the output of gvim.
+  CheckNotGui
+  CheckUnix
+  CheckEnglish
+  let l = systemlist(GetVimProg() .. ' --ttyfail')
+  call assert_equal(['Vim: Warning: Output is not to a terminal',
+        \ 'Vim: Warning: Input is not from a terminal'], l)
+endfunc
+
+" Test for the "-w scriptout" argument
+func Test_w_arg()
+  " Can't catch the output of gvim.
+  CheckNotGui
+  call writefile(["iVim Editor\<Esc>:q!\<CR>"], 'Xscriptin', 'b')
+  if RunVim([], [], '-s Xscriptin -w Xscriptout')
+    call assert_equal(["iVim Editor\e:q!\r"], readfile('Xscriptout'))
+    call delete('Xscriptout')
+  endif
+  call delete('Xscriptin')
+
+  " Test for failing to open the script output file. This test works only when
+  " the language is English.
+  if v:lang == "C" || v:lang =~ '^[Ee]n'
+    call mkdir("Xdir")
+    let m = system(GetVimCommand() .. " -w Xdir")
+    call assert_equal("Cannot open for script output: \"Xdir\"\n", m)
+    call delete("Xdir", 'rf')
+  endif
+endfunc
+
+" Test for the "-s scriptin" argument
+func Test_s_arg()
+  " Can't catch the output of gvim.
+  CheckNotGui
+  CheckEnglish
+  " Test for failing to open the script input file.
+  let m = system(GetVimCommand() .. " -s abcxyz")
+  call assert_equal("Cannot open for reading: \"abcxyz\"\n", m)
+
+  call writefile([], 'Xinput')
+  let m = system(GetVimCommand() .. " -s Xinput -s Xinput")
+  call assert_equal("Attempt to open script file again: \"-s Xinput\"\n", m)
+  call delete('Xinput')
+endfunc
+
+" Test for the "-n" (no swap file) argument
+func Test_n_arg()
+  let after =<< trim [CODE]
+    call assert_equal(0, &updatecount)
+    call writefile(v:errors, 'Xtestout')
+    qall
+  [CODE]
+  if RunVim([], after, '-n')
+    call assert_equal([], readfile('Xtestout'))
+    call delete('Xtestout')
+  endif
+  call delete('Xafter')
+endfunc
+
+" Test for the "-h" (help) argument
+func Test_h_arg()
+  " Can't catch the output of gvim.
+  CheckNotGui
+  let l = systemlist(GetVimProg() .. ' -h')
+  call assert_match('^VIM - Vi IMproved', l[0])
+  let l = systemlist(GetVimProg() .. ' -?')
+  call assert_match('^VIM - Vi IMproved', l[0])
+endfunc
+
+" Test for the "-F" (farsi) argument
+func Test_F_arg()
+  " Can't catch the output of gvim.
+  CheckNotGui
+  let l = systemlist(GetVimProg() .. ' -F')
+  call assert_match('^E27:', l[0])
+endfunc
+
+" Test for the "-E" (improved Ex mode) argument
+func Test_E_arg()
+  let after =<< trim [CODE]
+    call assert_equal('cv', mode(1))
+    call writefile(v:errors, 'Xtestout')
+    qall
+  [CODE]
+  if RunVim([], after, '-E')
+    call assert_equal([], readfile('Xtestout'))
+    call delete('Xtestout')
+  endif
+  call delete('Xafter')
+endfunc
+
+" Test for too many edit argument errors
+func Test_too_many_edit_args()
+  " Can't catch the output of gvim.
+  CheckNotGui
+  CheckEnglish
+  let l = systemlist(GetVimProg() .. ' - -')
+  call assert_match('^Too many edit arguments: "-"', l[1])
+endfunc
+
+" vim: shiftwidth=2 sts=2 expandtab

--- a/src/testdir/test_textformat.vim
+++ b/src/testdir/test_textformat.vim
@@ -1026,6 +1026,41 @@ func Test_comment_nested()
   %bw!
 endfunc
 
+" Test for a space character in 'comments' setting
+func Test_comment_space()
+  new
+  setlocal comments=b:\ > fo+=ro
+  exe "normal i> B\nD\<C-C>ggOA\<C-C>joC"
+  exe "normal Go > F\nH\<C-C>kOE\<C-C>joG"
+  let expected =<< trim END
+    A
+    > B
+    C
+    D
+     > E
+     > F
+     > G
+     > H
+  END
+  call assert_equal(expected, getline(1, '$'))
+  %bw!
+endfunc
+
+" Test for the 'O' flag in 'comments'
+func Test_comment_O()
+  new
+  setlocal comments=Ob:* fo+=ro
+  exe "normal i* B\nD\<C-C>kOA\<C-C>joC"
+  let expected =<< trim END
+    A
+    * B
+    * C
+    * D
+  END
+  call assert_equal(expected, getline(1, '$'))
+  %bw!
+endfunc
+
 " Test for 'a' and 'w' flags in 'formatoptions'
 func Test_fo_a_w()
   new
@@ -1035,4 +1070,23 @@ func Test_fo_a_w()
   %bw!
 endfunc
 
+" Test for 'j' flag in 'formatoptions'
+func Test_fo_j()
+  new
+  setlocal fo+=j comments=://
+  call setline(1, ['i++; // comment1', '           // comment2'])
+  normal J
+  call assert_equal('i++; // comment1 comment2', getline(1))
+  setlocal fo-=j
+  call setline(1, ['i++; // comment1', '           // comment2'])
+  normal J
+  call assert_equal('i++; // comment1 // comment2', getline(1))
+  " Test with nested comments
+  setlocal fo+=j comments=n:>,n:)
+  call setline(1, ['i++; > ) > ) comment1', '           > ) comment2'])
+  normal J
+  call assert_equal('i++; > ) > ) comment1 comment2', getline(1))
+  %bw!
+endfunc
+
 " vim: shiftwidth=2 sts=2 expandtab

--- a/src/testdir/test_trycatch.vim
+++ b/src/testdir/test_trycatch.vim
@@ -2012,9 +2012,7 @@ endfunc
 " Test for verbose messages with :try :catch, and :finally                 {{{1
 func Test_try_catch_verbose()
   " This test works only when the language is English
-  if v:lang != "C" && v:lang !~ '^[Ee]n'
-    return
-  endif
+  CheckEnglish
 
   set verbose=14
 

--- a/src/testdir/test_viminfo.vim
+++ b/src/testdir/test_viminfo.vim
@@ -760,6 +760,11 @@ func Test_viminfo_perm()
   call setfperm('Xviminfo', '--x------')
   call assert_fails('rviminfo Xviminfo', 'E195:')
   call delete('Xviminfo')
+
+  " Try to write the viminfo to a directory
+  call mkdir('Xdir')
+  call assert_fails('wviminfo Xdir', 'E886:')
+  call delete('Xdir', 'rf')
 endfunc
 
 " Test for writing to an existing viminfo file merges the file marks

--- a/src/version.c
+++ b/src/version.c
@@ -739,6 +739,8 @@ static char *(features[]) =
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    509,
+/**/
     508,
 /**/
     507,