comctl32/trackbar: Fix TBM_SETRANGEMAX handling when new limit is less than current min boundary.

dlls/comctl32/tests/trackbar.c

@@ -775,6 +775,32 @@ static void test_range(void)
     SendMessageA(hWndTrackbar, TBM_GETTHUMBRECT, 0, (LPARAM)&rect1);
     ok(EqualRect(&rect1, &rect2), "thumb rectangle not updated\n");
 
+    /* test position update on range change */
+
+    /* set to [20, 50], position at 30, reduce range to [20,25] */
+    SendMessageA(hWndTrackbar, TBM_SETRANGEMIN, FALSE, 20);
+    SendMessageA(hWndTrackbar, TBM_SETRANGEMAX, FALSE, 50);
+    SendMessageA(hWndTrackbar, TBM_SETPOS, FALSE, 30);
+    SendMessageA(hWndTrackbar, TBM_SETRANGEMAX, FALSE, 25);
+    r = SendMessageA(hWndTrackbar, TBM_GETPOS, 0, 0);
+    ok(r == 25, "Unexpected position %d\n", r);
+
+    /* set to [20, 50], position at 30, flip max to 10 */
+    SendMessageA(hWndTrackbar, TBM_SETRANGEMIN, FALSE, 20);
+    SendMessageA(hWndTrackbar, TBM_SETRANGEMAX, FALSE, 50);
+    SendMessageA(hWndTrackbar, TBM_SETPOS, FALSE, 30);
+    SendMessageA(hWndTrackbar, TBM_SETRANGEMAX, FALSE, 10);
+    r = SendMessageA(hWndTrackbar, TBM_GETPOS, 0, 0);
+    ok(r == 20, "Unexpected position %d\n", r);
+
+    /* set to [20, 50], position at 30, flip min to 70 */
+    SendMessageA(hWndTrackbar, TBM_SETRANGEMIN, FALSE, 20);
+    SendMessageA(hWndTrackbar, TBM_SETRANGEMAX, FALSE, 50);
+    SendMessageA(hWndTrackbar, TBM_SETPOS, FALSE, 30);
+    SendMessageA(hWndTrackbar, TBM_SETRANGEMIN, FALSE, 70);
+    r = SendMessageA(hWndTrackbar, TBM_GETPOS, 0, 0);
+    ok(r == 70, "Unexpected position %d\n", r);
+
     DestroyWindow(hWndTrackbar);
 }
 

dlls/comctl32/trackbar.c

@@ -1275,10 +1275,11 @@ static inline LRESULT
 TRACKBAR_SetRangeMax (TRACKBAR_INFO *infoPtr, BOOL redraw, LONG lMax)
 {
     BOOL changed = infoPtr->lRangeMax != lMax;
+    LONG rightmost = max(lMax, infoPtr->lRangeMin);
 
     infoPtr->lRangeMax = lMax;
-    if (infoPtr->lPos > infoPtr->lRangeMax) {
-        infoPtr->lPos = infoPtr->lRangeMax;
+    if (infoPtr->lPos > rightmost) {
+        infoPtr->lPos = rightmost;
         infoPtr->flags |= TB_THUMBPOSCHANGED;
     }