vim-patch:8.2.0407: no early check if :find and :sfind have an argument

Problem:    No early check if :find and :sfind have an argument.
Solution:   Add EX_NEEDARG.
https://github.com/vim/vim/commit/2d10cd478047df8ba144d4b0fcc46480993af57f

Cherry-pick Test_find_cmd() from patch v8.2.0270.
Use "exe 'cd ' . save_dir" pattern
because patches v8.1.1291, v8.1.2278 are not ported yet.
Cherry-pick modeline from patch v8.1.1432.

3 files changed, 49 insertions, 6 deletions

diff --git a/src/nvim/ex_cmds.lua b/src/nvim/ex_cmds.lua
index dd2ad647f7..069d5d461b 100644
--- a/src/nvim/ex_cmds.lua
+++ b/src/nvim/ex_cmds.lua
@@ -971,7 +971,7 @@ module.cmds = {
   },
   {
     command='find',
-    flags=bit.bor(RANGE, BANG, FILE1, CMDARG, ARGOPT, TRLBAR),
+    flags=bit.bor(RANGE, BANG, FILE1, CMDARG, ARGOPT, TRLBAR, NEEDARG),
     addr_type='ADDR_OTHER',
     func='ex_find',
   },
@@ -2425,7 +2425,7 @@ module.cmds = {
   },
   {
     command='sfind',
-    flags=bit.bor(BANG, FILE1, RANGE, CMDARG, ARGOPT, TRLBAR),
+    flags=bit.bor(BANG, FILE1, RANGE, CMDARG, ARGOPT, TRLBAR, NEEDARG),
     addr_type='ADDR_OTHER',
     func='ex_splitview',
   },
diff --git a/src/nvim/testdir/test_find_complete.vim b/src/nvim/testdir/test_find_complete.vim
index a7bc135d47..0a00d9432f 100644
--- a/src/nvim/testdir/test_find_complete.vim
+++ b/src/nvim/testdir/test_find_complete.vim
@@ -15,22 +15,22 @@ func Test_find_complete()
 
   new
   set path=
-  call assert_fails('call feedkeys(":find\t\n", "xt")', 'E345:')
+  call assert_fails('call feedkeys(":find \t\n", "xt")', 'E471:')
   close
 
   new
   set path=.
-  call assert_fails('call feedkeys(":find\t\n", "xt")', 'E32:')
+  call assert_fails('call feedkeys(":find \t\n", "xt")', 'E471:')
   close
 
   new
   set path=.,,
-  call assert_fails('call feedkeys(":find\t\n", "xt")', 'E32:')
+  call assert_fails('call feedkeys(":find \t\n", "xt")', 'E471:')
   close
 
   new
   set path=./**
-  call assert_fails('call feedkeys(":find\t\n", "xt")', 'E32:')
+  call assert_fails('call feedkeys(":find \t\n", "xt")', 'E471:')
   close
 
   " We shouldn't find any file till this point
diff --git a/src/nvim/testdir/test_findfile.vim b/src/nvim/testdir/test_findfile.vim
index f5488a6a27..2195bf527e 100644
--- a/src/nvim/testdir/test_findfile.vim
+++ b/src/nvim/testdir/test_findfile.vim
@@ -184,3 +184,46 @@ func Test_finddir_error()
   call assert_fails('call finddir("x", "**x")', 'E343:')
   call assert_fails('call finddir("x", repeat("x", 5000))', 'E854:')
 endfunc
+
+" Test for the :find, :sfind and :tabfind commands
+func Test_find_cmd()
+  new
+  let save_path = &path
+  let save_dir = getcwd()
+  set path=.,./**/*
+  call CreateFiles()
+  cd Xdir1
+  " Test for :find
+  find foo
+  call assert_equal('foo', expand('%:.'))
+  2find foo
+  call assert_equal('Xdir2/foo', expand('%:.'))
+  call assert_fails('3find foo', 'E347:')
+  " Test for :sfind
+  enew
+  sfind barfoo
+  call assert_equal('Xdir2/Xdir3/barfoo', expand('%:.'))
+  call assert_equal(3, winnr('$'))
+  close
+  call assert_fails('sfind baz', 'E345:')
+  call assert_equal(2, winnr('$'))
+  " Test for :tabfind
+  enew
+  tabfind foobar
+  call assert_equal('Xdir2/foobar', expand('%:.'))
+  call assert_equal(2, tabpagenr('$'))
+  tabclose
+  call assert_fails('tabfind baz', 'E345:')
+  call assert_equal(1, tabpagenr('$'))
+  " call chdir(save_dir)
+  exe 'cd ' . save_dir
+  call CleanFiles()
+  let &path = save_path
+  close
+
+  call assert_fails('find', 'E471:')
+  call assert_fails('sfind', 'E471:')
+  call assert_fails('tabfind', 'E471:')
+endfunc
+
+" vim: shiftwidth=2 sts=2 expandtab