diff --git a/src/testdir/test_syntax.vim b/src/testdir/test_syntax.vim
index 7f1e5f0..73573ff 100644
--- a/src/testdir/test_syntax.vim
+++ b/src/testdir/test_syntax.vim
@@ -652,7 +652,7 @@
 	\ "\t}",
 	\ "\tNote: asdf",
 	\ '}',
-	\ ], 'Xtest.c')
+	\ ], 'Xtest.c', 'D')
 
   " This makes the default for 'background' use "dark", check that the
   " response to t_RB corrects it to "light".
@@ -670,7 +670,6 @@
   call StopVimInTerminal(buf)
 
   let $COLORFGBG = ''
-  call delete('Xtest.c')
 endfun
 
 " Test \z(...) along with \z1
@@ -704,10 +703,10 @@
 endfunc
 
 func Test_syntax_after_bufdo()
-  call writefile(['/* aaa comment */'], 'Xaaa.c')
-  call writefile(['/* bbb comment */'], 'Xbbb.c')
-  call writefile(['/* ccc comment */'], 'Xccc.c')
-  call writefile(['/* ddd comment */'], 'Xddd.c')
+  call writefile(['/* aaa comment */'], 'Xaaa.c', 'D')
+  call writefile(['/* bbb comment */'], 'Xbbb.c', 'D')
+  call writefile(['/* ccc comment */'], 'Xccc.c', 'D')
+  call writefile(['/* ddd comment */'], 'Xddd.c', 'D')
 
   let bnr = bufnr('%')
   new Xaaa.c
@@ -735,10 +734,6 @@
   bwipe! Xccc.c
   bwipe! Xddd.c
   syntax off
-  call delete('Xaaa.c')
-  call delete('Xbbb.c')
-  call delete('Xccc.c')
-  call delete('Xddd.c')
 endfunc
 
 func Test_syntax_foldlevel()