diff --git a/src/testdir/test_highlight.vim b/src/testdir/test_highlight.vim
index 78dbead..09f8067 100644
--- a/src/testdir/test_highlight.vim
+++ b/src/testdir/test_highlight.vim
@@ -578,12 +578,13 @@
     throw 'Skipped: cannot make screendumps'
   endif
 
-  call writefile([
-	\ 'set cursorline cursorcolumn rnu',
-	\ 'call setline(1, ["","1111111111","22222222222","3 here 3",""])',
-	\ 'set wincolor=Pmenu',
-	\ '/here',
-	\ ], 'Xtest_wincolor')
+  let lines =<< trim END
+	set cursorline cursorcolumn rnu
+	call setline(1, ["","1111111111","22222222222","3 here 3",""])
+	set wincolor=Pmenu
+	/here
+  END
+  call writefile(lines, 'Xtest_wincolor')
   let buf = RunVimInTerminal('-S Xtest_wincolor', {'rows': 8})
   call term_wait(buf)
   call term_sendkeys(buf, "2G5lvj")