PROC MACRO INPUT (PRETTY-PRINTED): struct M ( $crate :: S ) ;
PROC MACRO INPUT: TokenStream [
    Ident {
        ident: "struct",
        span: #2 bytes(LO..HI),
    },
    Ident {
        ident: "M",
        span: #2 bytes(LO..HI),
    },
    Group {
        delimiter: Parenthesis,
        stream: TokenStream [
            Ident {
                ident: "$crate",
                span: #2 bytes(LO..HI),
            },
            Punct {
                ch: ':',
                spacing: Joint,
                span: #2 bytes(LO..HI),
            },
            Punct {
                ch: ':',
                spacing: Alone,
                span: #2 bytes(LO..HI),
            },
            Ident {
                ident: "S",
                span: #2 bytes(LO..HI),
            },
        ],
        span: #2 bytes(LO..HI),
    },
    Punct {
        ch: ';',
        spacing: Alone,
        span: #2 bytes(LO..HI),
    },
]
ATTRIBUTE INPUT (PRETTY-PRINTED): struct A(crate::S);
ATTRIBUTE INPUT: TokenStream [
    Ident {
        ident: "struct",
        span: #2 bytes(LO..HI),
    },
    Ident {
        ident: "A",
        span: #2 bytes(LO..HI),
    },
    Group {
        delimiter: Parenthesis,
        stream: TokenStream [
            Ident {
                ident: "$crate",
                span: #2 bytes(LO..HI),
            },
            Punct {
                ch: ':',
                spacing: Joint,
                span: #2 bytes(LO..HI),
            },
            Punct {
                ch: ':',
                spacing: Alone,
                span: #2 bytes(LO..HI),
            },
            Ident {
                ident: "S",
                span: #2 bytes(LO..HI),
            },
        ],
        span: #2 bytes(LO..HI),
    },
    Punct {
        ch: ';',
        spacing: Alone,
        span: #2 bytes(LO..HI),
    },
]