diff --git a/dlls/riched32/tests/editor.c b/dlls/riched32/tests/editor.c
index 6fe40055992..7751d2b4028 100644
--- a/dlls/riched32/tests/editor.c
+++ b/dlls/riched32/tests/editor.c
@@ -104,7 +104,7 @@ static void test_WM_SETTEXT(void)
    * for line breaking (only \n adds a line break)
    */
 
-  for (i = 0; i < sizeof(testitems)/sizeof(testitems[0]); i++) {
+  for (i = 0; i < ARRAY_SIZE(testitems); i++) {
 
     char buf[1024] = {0};
     LRESULT result;
@@ -410,7 +410,7 @@ static void test_EM_GETLINE(void)
   }
 
   memset(origdest, 0xBB, nBuf);
-  for (i = 0; i < sizeof(gl)/sizeof(struct getline_s); i++)
+  for (i = 0; i < ARRAY_SIZE(gl); i++)
   {
     int nCopied, expected_nCopied, expected_bytes_written;
     char gl_text[1024];
@@ -504,7 +504,7 @@ static void test_EM_LINELENGTH(void)
   }
   ok(result == 9, "Incorrect line count of %ld\n", result);
 
-  for (i = 0; i < sizeof(offset_test)/sizeof(offset_test[0]); i++) {
+  for (i = 0; i < ARRAY_SIZE(offset_test); i++) {
     result = SendMessageA(hwndRichEdit, EM_LINELENGTH, offset_test[i][0], 0);
     ok(result == offset_test[i][1], "Length of line at offset %d is %ld, expected %d\n",
        offset_test[i][0], result, offset_test[i][1]);
@@ -525,7 +525,7 @@ static void test_EM_LINELENGTH(void)
            {16, 4}, /* Line 3: |wine */
     };
     SendMessageA(hwndRichEdit, WM_SETTEXT, 0, (LPARAM)text1);
-    for (i = 0; i < sizeof(offset_test1)/sizeof(offset_test1[0]); i++) {
+    for (i = 0; i < ARRAY_SIZE(offset_test1); i++) {
       result = SendMessageA(hwndRichEdit, EM_LINELENGTH, offset_test1[i][0], 0);
       todo_wine_if (offset_test1[i][2])
           ok(result == offset_test1[i][1], "Length of line at offset %d is %ld, expected %d\n",
@@ -781,20 +781,17 @@ static void test_EM_FINDTEXT(void)
   HWND hwndRichEdit = new_richedit(NULL);
 
   /* Empty rich edit control */
-  run_tests_EM_FINDTEXT(hwndRichEdit, "1", find_tests,
-      sizeof(find_tests)/sizeof(struct find_s));
+  run_tests_EM_FINDTEXT(hwndRichEdit, "1", find_tests, ARRAY_SIZE(find_tests));
 
   SendMessageA(hwndRichEdit, WM_SETTEXT, 0, (LPARAM)haystack);
 
   /* Haystack text */
-  run_tests_EM_FINDTEXT(hwndRichEdit, "2", find_tests2,
-      sizeof(find_tests2)/sizeof(struct find_s));
+  run_tests_EM_FINDTEXT(hwndRichEdit, "2", find_tests2, ARRAY_SIZE(find_tests2));
 
   SendMessageA(hwndRichEdit, WM_SETTEXT, 0, (LPARAM)haystack2);
 
   /* Haystack text 2 (with EOL characters) */
-  run_tests_EM_FINDTEXT(hwndRichEdit, "3", find_tests3,
-      sizeof(find_tests3)/sizeof(struct find_s));
+  run_tests_EM_FINDTEXT(hwndRichEdit, "3", find_tests3, ARRAY_SIZE(find_tests3));
 
   DestroyWindow(hwndRichEdit);
 }
@@ -1178,7 +1175,7 @@ static void test_enter(void)
   HWND hwndRichEdit = new_richedit(NULL);
   UINT i,j;
 
-  for (i = 0; i < sizeof(testenteritems)/sizeof(testenteritems[0]); i++) {
+  for (i = 0; i < ARRAY_SIZE(testenteritems); i++) {
 
     char buf[1024] = {0};
     LRESULT result;
@@ -1321,7 +1318,7 @@ static void test_EM_EXSETSEL(void)
 {
     HWND hwndRichEdit = new_richedit(NULL);
     int i;
-    const int num_tests = sizeof(exsetsel_tests)/sizeof(struct exsetsel_s);
+    const int num_tests = ARRAY_SIZE(exsetsel_tests);
 
     /* sending some text to the window */
     SendMessageA(hwndRichEdit, WM_SETTEXT, 0, (LPARAM)"testing selection");
@@ -1378,7 +1375,7 @@ static void test_EM_SETSEL(void)
     char buffA[32] = {0};
     HWND hwndRichEdit = new_richedit(NULL);
     int i;
-    const int num_tests = sizeof(exsetsel_tests)/sizeof(struct exsetsel_s);
+    const int num_tests = ARRAY_SIZE(exsetsel_tests);
 
     /* sending some text to the window */
     SendMessageA(hwndRichEdit, WM_SETTEXT, 0, (LPARAM)"testing selection");