processFont method
Implementation
FontExpression processFont() {
// Process all parts of the font expression.
FontExpression? fontSize;
FontExpression? fontFamily;
for (; _index < _exprs.expressions.length; _index++) {
// Order is font-size font-family
fontSize ??= processFontSize();
fontFamily ??= processFontFamily();
//TODO(terry): Handle font-weight, font-style, and font-variant. See
// https://github.com/dart-lang/csslib/issues/3
// https://github.com/dart-lang/csslib/issues/4
// https://github.com/dart-lang/csslib/issues/5
}
return FontExpression(_exprs.span,
size: fontSize!.font.size,
lineHeight: fontSize.font.lineHeight,
family: fontFamily!.font.family);
}