Check for DelphiObject = nil immediately in TPyDelphiObject.SetAttrO and TPyDelphiObject.GetAttrO

Author: pyscripter

Source/WrapDelphi.pas

@@ -1026,7 +1026,8 @@ implementation
  rs_ErrAttrGet = 'Error in getting property "%s".'#$A'Error: %s';
  rs_UnknownAttribute = 'Unknown attribute';
  rs_ErrIterSupport = 'Wrapper %s does not support iterators';
- rs_ErrAttrSetr = 'Error in setting property %s'#$A'Error: %s';
+ rs_ErrAttrSet = 'Error in setting property %s'#$A'Error: %s';
+ rs_ErrObjectDestroyed = 'Trying to access a destroyed pascal object';
  rs_IncompatibleClasses = 'Incompatible classes';
  rs_IncompatibleRecords = 'Incompatible record types';
  rs_IncompatibleInterfaces = 'Incompatible interfaces';
@@ -1550,7 +1551,7 @@ function TExposedGetSet.SetterWrapper(AObj, AValue: PPyObject; AContext: Pointer
  if Result <> 0 then
  with GetPythonEngine do
  PyErr_SetObject (PyExc_AttributeError^,
- PyUnicodeFromString(Format(rs_ErrAttrSetr, [FRttiMember.Name, ErrMsg])));
+ PyUnicodeFromString(Format(rs_ErrAttrSet, [FRttiMember.Name, ErrMsg])));
 end;
 
 { TExposedField }
@@ -1646,7 +1647,7 @@ function TExposedEvent.SetterWrapper(AObj, AValue: PPyObject; AContext: Pointer)
  if Result <> 0 then
  with GetPythonEngine do
  PyErr_SetObject (PyExc_AttributeError^,
- PyUnicodeFromString(Format(rs_ErrAttrSetr, [FRttiMember.Name, ErrMsg])));
+ PyUnicodeFromString(Format(rs_ErrAttrSet, [FRttiMember.Name, ErrMsg])));
 end;
 
 { TExposedIndexedProperty }
@@ -3434,7 +3435,7 @@ function TPyRttiObject.SetAttrO(key, value: PPyObject): Integer;
  if Result <> 0 then
  with GetPythonEngine do
  PyErr_SetObject(PyExc_AttributeError^, PyUnicodeFromString(
- Format(rs_ErrAttrSetr, [KeyName, ErrMsg])));
+ Format(rs_ErrAttrSet, [KeyName, ErrMsg])));
 end;
 
 function TPyRttiObject.SetProps(args, keywords: PPyObject): PPyObject;
@@ -3543,6 +3544,7 @@ function TPyDelphiObject.GetAttrO(key: PPyObject): PPyObject;
 var
  KeyName: string;
  ErrMsg : string;
+ PyEngine: TPythonEngine;
  {$IFNDEF EXTENDED_RTTI}
  {$IFNDEF FPC}
  Info: PMethodInfoHeader;
@@ -3554,16 +3556,24 @@ function TPyDelphiObject.GetAttrO(key: PPyObject): PPyObject;
  RttiType: TRttiStructuredType;
  {$ENDIF}
 begin
- Result := inherited GetAttrO(key);
- if GetPythonEngine.PyErr_Occurred = nil then Exit; // We found what we wanted
+ Result := nil;
+ PyEngine := GetPythonEngine;
 
- // should not happen
- if not (Assigned(DelphiObject) and
- CheckStrAttribute(Key, 'GetAttrO key parameter', KeyName))
- then
+ // If DelphiObject is nil Exit immediately with an error
+ if not Assigned(DelphiObject) then
+ begin
+ PyEngine.PyErr_SetObject(PyEngine.PyExc_AttributeError^,
+ PyEngine.PyUnicodeFromString(rs_ErrObjectDestroyed));
  Exit;
+ end;
+
+ if not CheckStrAttribute(Key, 'GetAttrO key parameter', KeyName) then
+ Exit; // should not happen
+
+ Result := inherited GetAttrO(key);
+ if PyEngine.PyErr_Occurred = nil then Exit; // We found what we wanted
 
- GetPythonEngine.PyErr_Clear;
+ PyEngine.PyErr_Clear;
 {$IFDEF EXTENDED_RTTI}
  // Use RTTI
  if Assigned(DelphiObject) then begin
@@ -3620,17 +3630,17 @@ function TPyDelphiObject.GetAttrO(key: PPyObject): PPyObject;
  {$ELSE FPC}
  if GetTypeData(PropInfo^.PropType^)^.BaseType^ = TypeInfo(Boolean) then
  {$ENDIF FPC}
- Result := GetPythonEngine.VariantAsPyObject(Boolean(GetOrdProp(Self.DelphiObject, PropInfo)))
+ Result := PyEngine.VariantAsPyObject(Boolean(GetOrdProp(Self.DelphiObject, PropInfo)))
  else
  {$IFDEF FPC}
- Result := GetPythonEngine.PyUnicodeFromString(GetEnumName(PropInfo^.PropType,
+ Result := PyEngine.PyUnicodeFromString(GetEnumName(PropInfo^.PropType,
  {$ELSE FPC}
- Result := GetPythonEngine.PyUnicodeFromString(GetEnumName(PropInfo^.PropType^,
+ Result := PyEngine.PyUnicodeFromString(GetEnumName(PropInfo^.PropType^,
  {$ENDIF FPC}
  GetOrdProp(Self.DelphiObject, PropInfo)));
  end
  end else
- Result := GetPythonEngine.VariantAsPyObject(GetPropValue(DelphiObject, PropInfo));
+ Result := PyEngine.VariantAsPyObject(GetPropValue(DelphiObject, PropInfo));
  end;
  except
  on E: Exception do begin
@@ -3640,9 +3650,8 @@ function TPyDelphiObject.GetAttrO(key: PPyObject): PPyObject;
  end;
 {$ENDIF}
  if not Assigned(Result) then
- with GetPythonEngine do
- PyErr_SetObject (PyExc_AttributeError^,
- PyUnicodeFromString(Format(rs_ErrAttrGet,[KeyName, ErrMsg])));
+ PyEngine.PyErr_SetObject (PyEngine.PyExc_AttributeError^,
+ PyEngine.PyUnicodeFromString(Format(rs_ErrAttrGet,[KeyName, ErrMsg])));
 end;
 
 function TPyDelphiObject.GetContainerAccess: TContainerAccess;
@@ -3944,11 +3953,16 @@ function TPyDelphiObject.SetAttrO(key, value: PPyObject): Integer;
  Result := -1;
  PyEngine := GetPythonEngine;
 
- // should not happen
- if not (Assigned(DelphiObject) and
- CheckStrAttribute(Key, 'SetAttrO key parameter', KeyName))
- then
+ // If DelphiObject is nil Exit immediately with an error
+ if not Assigned(DelphiObject) then
+ begin
+ PyEngine.PyErr_SetObject(PyEngine.PyExc_AttributeError^,
+ PyEngine.PyUnicodeFromString(rs_ErrObjectDestroyed));
  Exit;
+ end;
+
+ if not CheckStrAttribute(Key, 'SetAttrO key parameter', KeyName) then
+ Exit; // should not happen
 
  // Only call the inherited method at this stage if the attribute exists
  PyObj := PyEngine.PyObject_GenericGetAttr(GetSelf, key);
@@ -3989,8 +4003,8 @@ function TPyDelphiObject.SetAttrO(key, value: PPyObject): Integer;
  Result := inherited SetAttrO(key, value);
  if Result <> 0 then
  with PyEngine do
- PyErr_SetObject(PyEngine.PyExc_AttributeError^, PyUnicodeFromString(
- Format(rs_ErrAttrSetr, [KeyName, ErrMsg])));
+ PyErr_SetObject(PyExc_AttributeError^, PyUnicodeFromString(
+ Format(rs_ErrAttrSet, [KeyName, ErrMsg])));
 end;
 
 procedure TPyDelphiObject.SetDelphiObject(const Value: TObject);