QMessageBox: Move enum static assertions to cpp file

Move static assertions for StandardButton and ButtonRole enums from
header to cpp file.

Use qToUnderlying instead of casting and assert types where possible.

Amends 773f9ab0189bbb439c3066695c947b11a20c484f.

Found in API-Review.

Change-Id: Ia52886e6e33a3b94b327d17d1453e18febe6dd50
Found-by: Giuseppe D'Angelo <giuseppe.dangelo@kdab.com>
Task-number: QTBUG-119952
Pick-to: 6.7 6.6 6.5
Reviewed-by: Marc Mutz <marc.mutz@qt.io>

2 files changed, 14 insertions, 7 deletions

diff --git a/src/widgets/dialogs/qmessagebox.cpp b/src/widgets/dialogs/qmessagebox.cpp
index 9277c5e42a..ded02a756a 100644
--- a/src/widgets/dialogs/qmessagebox.cpp
+++ b/src/widgets/dialogs/qmessagebox.cpp
@@ -56,6 +56,20 @@ HMENU qt_getWindowsSystemMenu(const QWidget *w)
 }
 #endif
 
+static_assert(qToUnderlying(QMessageBox::ButtonRole::NRoles) ==
+              qToUnderlying(QDialogButtonBox::ButtonRole::NRoles),
+              "QMessageBox::ButtonRole and QDialogButtonBox::ButtonRole out of sync!");
+
+static_assert(std::is_same_v<std::underlying_type_t<QMessageBox::ButtonRole>,
+                             std::underlying_type_t<QDialogButtonBox::ButtonRole>>);
+
+// StandardButton enums have different underlying types
+// => qToUnderlying and std::is_same_v won't work
+// ### Qt 7: make them have the same underlying type
+static_assert(static_cast<int>(QMessageBox::StandardButton::LastButton) ==
+              static_cast<int>(QDialogButtonBox::StandardButton::LastButton),
+              "QMessageBox::StandardButton and QDialogButtonBox::StandardButton out of sync!");
+
 enum Button { Old_Ok = 1, Old_Cancel = 2, Old_Yes = 3, Old_No = 4, Old_Abort = 5, Old_Retry = 6,
               Old_Ignore = 7, Old_YesAll = 8, Old_NoAll = 9, Old_ButtonMask = 0xFF,
               NewButtonMask = 0xFFFFFC00 };
diff --git a/src/widgets/dialogs/qmessagebox.h b/src/widgets/dialogs/qmessagebox.h
index 5db4f6e67e..897f02c5fc 100644
--- a/src/widgets/dialogs/qmessagebox.h
+++ b/src/widgets/dialogs/qmessagebox.h
@@ -66,9 +66,6 @@ public:
         NRoles
     };
     Q_ENUM(ButtonRole)
-    static_assert(static_cast<int>(ButtonRole::NRoles) ==
-                  static_cast<int>(QDialogButtonBox::ButtonRole::NRoles),
-                  "QMessageBox::ButtonRole and QDialogButtonBox::ButtonRole out of sync!");
 
     enum StandardButton {
         // keep this in sync with QDialogButtonBox::StandardButton and QPlatformDialogHelper::StandardButton
@@ -104,10 +101,6 @@ public:
         ButtonMask         = ~FlagMask          // obsolete
     };
     Q_ENUM(StandardButton);
-    static_assert(static_cast<int>(StandardButton::LastButton) ==
-                  static_cast<int>(QDialogButtonBox::StandardButton::LastButton),
-                  "QMessageBox::StandardButton and QDialogButtonBox::StandardButton out of sync!");
-
 
 #if QT_VERSION < QT_VERSION_CHECK(7, 0, 0)
     typedef StandardButton Button;