I think type is right here. theType is assigned from type and it has not been assigned at the point this exception is thrown. The whole block looks like:

                        } else if (type.isCoercibleTo(PDataType.DATE)) {
                            if (foundDate) {
                                throwTypeMismatch(node, type);
                            }
                            theType = type;
                            foundDate = true;
                        }