patch 8.2.2873: not enough tests for writing buffers

Problem:    Not enough tests for writing buffers.
Solution:   Add a few more tests. (Yegappan Lakshmanan, closes #8229)
diff --git a/src/testdir/test_cmdline.vim b/src/testdir/test_cmdline.vim
index bba7e72..d167d4c 100644
--- a/src/testdir/test_cmdline.vim
+++ b/src/testdir/test_cmdline.vim
@@ -1309,13 +1309,22 @@
   call delete('XtestCmdlineClearTabenter')
 endfunc
 
-" Test for failure in expanding special keywords in cmdline
+" Test for expanding special keywords in cmdline
 func Test_cmdline_expand_special()
   %bwipe!
   call assert_fails('e #', 'E499:')
   call assert_fails('e <afile>', 'E495:')
   call assert_fails('e <abuf>', 'E496:')
   call assert_fails('e <amatch>', 'E497:')
+
+  call writefile([], 'Xfile.cpp')
+  call writefile([], 'Xfile.java')
+  new Xfile.cpp
+  call feedkeys(":e %:r\<C-A>\<C-B>\"\<CR>", 'xt')
+  call assert_equal('"e Xfile.cpp Xfile.java', @:)
+  close
+  call delete('Xfile.cpp')
+  call delete('Xfile.java')
 endfunc
 
 func Test_cmdwin_jump_to_win()
@@ -1823,5 +1832,24 @@
   augroup END
 endfunc
 
+" Test for the 'suffixes' option
+func Test_suffixes_opt()
+  call writefile([], 'Xfile')
+  call writefile([], 'Xfile.c')
+  call writefile([], 'Xfile.o')
+  set suffixes=
+  call feedkeys(":e Xfi*\<C-A>\<C-B>\"\<CR>", 'xt')
+  call assert_equal('"e Xfile Xfile.c Xfile.o', @:)
+  set suffixes=.c
+  call feedkeys(":e Xfi*\<C-A>\<C-B>\"\<CR>", 'xt')
+  call assert_equal('"e Xfile Xfile.o Xfile.c', @:)
+  set suffixes=,,
+  call feedkeys(":e Xfi*\<C-A>\<C-B>\"\<CR>", 'xt')
+  call assert_equal('"e Xfile.c Xfile.o Xfile', @:)
+  set suffixes&
+  call delete('Xfile')
+  call delete('Xfile.c')
+  call delete('Xfile.o')
+endfunc
 
 " vim: shiftwidth=2 sts=2 expandtab