From f12f948849408881e2c4ea5a24b064b085c96fe0 Mon Sep 17 00:00:00 2001
From: Nikolay Sivov <bunglehead@gmail.com>
Date: Sun, 11 Oct 2009 18:23:16 +0400
Subject: [PATCH] comctl32/datetime: It isn't allowed to change DTS_SHOWNONE
 after creation.

---
 dlls/comctl32/datetime.c       | 20 ++++++++++++++++++++
 dlls/comctl32/tests/datetime.c | 22 ++++++++++++++++++++++
 2 files changed, 42 insertions(+)

diff --git a/dlls/comctl32/datetime.c b/dlls/comctl32/datetime.c
index 65f700505e8..2b3d64b713e 100644
--- a/dlls/comctl32/datetime.c
+++ b/dlls/comctl32/datetime.c
@@ -1251,6 +1251,23 @@ DATETIME_Size (DATETIME_INFO *infoPtr, INT width, INT height)
     return 0;
 }
 
+static LRESULT
+DATETIME_StyleChanging(DATETIME_INFO *infoPtr, WPARAM wStyleType, STYLESTRUCT *lpss)
+{
+    TRACE("(styletype=%lx, styleOld=0x%08x, styleNew=0x%08x)\n",
+          wStyleType, lpss->styleOld, lpss->styleNew);
+
+    /* block DTS_SHOWNONE change */
+    if ((lpss->styleNew ^ lpss->styleOld) & DTS_SHOWNONE)
+    {
+        if (lpss->styleOld & DTS_SHOWNONE)
+            lpss->styleNew |= DTS_SHOWNONE;
+        else
+            lpss->styleNew &= ~DTS_SHOWNONE;
+    }
+
+    return 0;
+}
 
 static LRESULT 
 DATETIME_StyleChanged(DATETIME_INFO *infoPtr, WPARAM wStyleType, const STYLESTRUCT *lpss)
@@ -1449,6 +1466,9 @@ DATETIME_WindowProc (HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lParam)
     case WM_COMMAND:
         return DATETIME_Command (infoPtr, wParam, lParam);
 
+    case WM_STYLECHANGING:
+        return DATETIME_StyleChanging(infoPtr, wParam, (LPSTYLESTRUCT)lParam);
+
     case WM_STYLECHANGED:
         return DATETIME_StyleChanged(infoPtr, wParam, (LPSTYLESTRUCT)lParam);
 
diff --git a/dlls/comctl32/tests/datetime.c b/dlls/comctl32/tests/datetime.c
index 973d41128e3..8a3ad031348 100644
--- a/dlls/comctl32/tests/datetime.c
+++ b/dlls/comctl32/tests/datetime.c
@@ -677,6 +677,27 @@ static void test_wm_set_get_text(void)
     DestroyWindow(hWnd);
 }
 
+static void test_dts_shownone(void)
+{
+    HWND hwnd;
+    DWORD style;
+
+    /* it isn't allowed to change DTS_SHOWNONE after creation */
+    hwnd = create_datetime_control(0);
+    style = GetWindowLong(hwnd, GWL_STYLE);
+    SetWindowLong(hwnd, GWL_STYLE, style | DTS_SHOWNONE);
+    style = GetWindowLong(hwnd, GWL_STYLE);
+    ok(!(style & DTS_SHOWNONE), "Expected DTS_SHOWNONE not to be set\n");
+    DestroyWindow(hwnd);
+
+    hwnd = create_datetime_control(DTS_SHOWNONE);
+    style = GetWindowLong(hwnd, GWL_STYLE);
+    SetWindowLong(hwnd, GWL_STYLE, style & ~DTS_SHOWNONE);
+    style = GetWindowLong(hwnd, GWL_STYLE);
+    ok(style & DTS_SHOWNONE, "Expected DTS_SHOWNONE to be set\n");
+    DestroyWindow(hwnd);
+}
+
 START_TEST(datetime)
 {
     HMODULE hComctl32;
@@ -704,4 +725,5 @@ START_TEST(datetime)
     test_dtm_set_range_swap_min_max();
     test_dtm_set_and_get_system_time();
     test_wm_set_get_text();
+    test_dts_shownone();
 }