Function unexpand_into_body_span_with_expn_kind

pub(crate) fn unexpand_into_body_span_with_expn_kind(
    original_span: Span,
    body_span: Span,
) -> Option<(Span, Option<ExpnKind>)>

Walks through the expansion ancestors of original_span to find a span that is contained in body_span and has the same [syntax context] as body_span.

If the returned span represents a bang-macro invocation (e.g. foo!(..)), the returned symbol will be the name of that macro (e.g. foo).