Function clippy_utils::is_direct_expn_of

pub fn is_direct_expn_of(span: Span, name: &str) -> Option<Span>

Returns the pre-expansion span if the span directly comes from an expansion of the macro name. The difference with is_expn_of is that in

foo!(bar!(42));

42 is considered expanded from foo! and bar! by is_expn_of but only from bar! by is_direct_expn_of.