Don't allow wxSpinCtrl range to include negative values if base != 10 (wxGTK)

Hexadecimal numbers are always unsigned in the native wxSpinCtrl
implementation under wxMSW so for the sake of consistency we need
to prevent:
- Setting a range including negative values if base == 16.
- Setting base != 10 if current range includes negative values.

See #18805.

interface/wx/spinctrl.h

@@ -149,8 +149,8 @@ public:
         the numbers in the specified base when they are changed using the spin
         control arrows.
 
-        @note Under wxMSW setting a base to 16 is allowed only if current range
+        @note Under wxMSW and wxGTK setting a base to 16 is allowed only if
-        does not include negative values.
+        current range does not include negative values.
 
         @param base
             Numeric base, currently only 10 and 16 are supported.
@@ -171,8 +171,8 @@ public:
         it is less than it now. However no @c wxEVT_SPINCTRL
         event is generated, even if it the value does change.
 
-        @note Under wxMSW setting a range including negative values is silently
+        @note Under wxMSW and wxGTK setting a range including negative values
-        ignored if current base is set to 16.
+        is silently ignored if current base is set to 16.
     */
     void SetRange(int minVal, int maxVal);
 

src/gtk/spinctrl.cpp

@@ -270,6 +270,12 @@ void wxSpinCtrlGTKBase::DoSetRange(double minVal, double maxVal)
 {
     wxCHECK_RET( (m_widget != NULL), wxT("invalid spin button") );
 
+    // Negative values in the range are allowed only if base == 10
+    if ( !wxSpinCtrlImpl::IsBaseCompatibleWithRange(minVal, maxVal, GetBase()) )
+    {
+        return;
+    }
+
     wxSpinCtrlEventDisabler disable(this);
     gtk_spin_button_set_range( GTK_SPIN_BUTTON(m_widget), minVal, maxVal);
 
@@ -447,6 +453,10 @@ bool wxSpinCtrl::SetBase(int base)
     if ( base == m_base )
         return true;
 
+    // For negative values in the range only base == 10 is allowed
+    if ( !wxSpinCtrlImpl::IsBaseCompatibleWithRange(static_cast<int>(DoGetMin()), static_cast<int>(DoGetMax()), base) )
+        return false;
+
     m_base = base;
 
     // We need to be able to enter letters for any base greater than 10.