Extract helper functions for wxFontWeight <-> int conversions

Make these functions available for the upcoming reuse in wxFont.

This is almost a pure refactoring, except that assert checking for the
symbolic weight validity was corrected (it was always true before due to
wrong use of "||" instead of "&&", so split it in 2 asserts to ensure
that this doesn't happen any more).

src/common/fontcmn.cpp

@@ -136,6 +136,55 @@ wxEMPTY_HANDLERS_TABLE(wxFont)
 // implementation
 // ============================================================================
 
+// ----------------------------------------------------------------------------
+// Local helpers
+// ----------------------------------------------------------------------------
+
+namespace
+{
+
+// Convert to/from wxFontWeight enum elements and numeric weight values.
+
+// This function interprets wxNORMAL, wxLIGHT and wxBOLD values in addition to
+// the actual wxFontWeight enum element values for compatibility. It does check
+// that it gets either the one or the other.
+int GetNumericWeightOf(wxFontWeight weight)
+{
+    // deal with compatibility constants
+    if (weight >= 90 && weight <= 92)
+    {
+        if (weight == 90 /* wxNORMAL */)
+            weight = wxFONTWEIGHT_NORMAL;
+        else if (weight == 91 /* wxLIGHT */)
+            weight = wxFONTWEIGHT_LIGHT;
+        else if (weight == 92 /* wxBOLD */)
+            weight = wxFONTWEIGHT_BOLD;
+    }
+
+    wxASSERT(weight > wxFONTWEIGHT_INVALID);
+    wxASSERT(weight <= wxFONTWEIGHT_MAX);
+    wxASSERT(weight % 100 == 0);
+
+    return weight;
+}
+
+// As its name indicates, this function returns the closest wxFontWeight enum
+// element, even if its value doesn't correspond to the given weight exactly.
+wxFontWeight GetWeightClosestToNumericValue(int numWeight)
+{
+    // round to nearest hundredth = wxFONTWEIGHT_ constant
+    int weight = ((numWeight + 50) / 100) * 100;
+
+    if (weight < wxFONTWEIGHT_THIN)
+        weight = wxFONTWEIGHT_THIN;
+    if (weight > wxFONTWEIGHT_MAX)
+        weight = wxFONTWEIGHT_MAX;
+
+    return static_cast<wxFontWeight>(weight);
+}
+
+} // anonymous namespace
+
 // ----------------------------------------------------------------------------
 // wxFontBase
 // ----------------------------------------------------------------------------
@@ -1234,36 +1283,14 @@ bool wxNativeFontInfo::FromUserString(const wxString& s)
 
 wxFontWeight wxNativeFontInfo::GetWeight() const
 {
-    // round to nearest hundredth = wxFONTWEIGHT_ constant
+    return GetWeightClosestToNumericValue(GetNumericWeight());
-    int weight = ((GetNumericWeight() + 50) / 100) * 100;
-
-    if (weight < wxFONTWEIGHT_THIN)
-        weight = wxFONTWEIGHT_THIN;
-    if (weight > wxFONTWEIGHT_MAX)
-        weight = wxFONTWEIGHT_MAX;
-
-    return (wxFontWeight)weight;
 }
 
 void wxNativeFontInfo::SetWeight(wxFontWeight weight)
 {
-    // deal with compatibility constants
+    const int numWeight = GetNumericWeightOf(weight);
-    if (weight >= 90 && weight <= 92)
+    if ( numWeight != GetNumericWeight() )
-    {
+        SetNumericWeight(numWeight);
-        if (weight == 90 /* wxNORMAL */)
-            weight = wxFONTWEIGHT_NORMAL;
-        else if (weight == 91 /* wxLIGHT */)
-            weight = wxFONTWEIGHT_LIGHT;
-        else if (weight == 92 /* wxBOLD */)
-            weight = wxFONTWEIGHT_BOLD;
-    }
-
-    wxASSERT(weight > wxFONTWEIGHT_INVALID || weight <= wxFONTWEIGHT_MAX);
-    wxASSERT(weight % 100 == 0);
-
-    wxFontWeight formerWeight = GetWeight();
-    if (formerWeight != weight)
-        SetNumericWeight(weight);
 }
 
 // wxFont <-> wxString utilities, used by wxConfig