1use std::hash::{Hash, Hasher};
2
3use proc_macro2::{Delimiter, TokenStream, TokenTree};
4
5pub struct TokenTreeHelper<'a>(pub &'a TokenTree);
6
7impl<'a> PartialEq for TokenTreeHelper<'a> {
8 fn eq(&self, other: &Self) -> bool {
9 use proc_macro2::Spacing;
10
11 match (self.0, other.0) {
12 (TokenTree::Group(g1), TokenTree::Group(g2)) => {
13 match (g1.delimiter(), g2.delimiter()) {
14 (Delimiter::Parenthesis, Delimiter::Parenthesis)
15 | (Delimiter::Brace, Delimiter::Brace)
16 | (Delimiter::Bracket, Delimiter::Bracket)
17 | (Delimiter::None, Delimiter::None) => {}
18 _ => return false,
19 }
20
21 let s1 = g1.stream().into_iter();
22 let mut s2 = g2.stream().into_iter();
23
24 for item1 in s1 {
25 let item2 = match s2.next() {
26 Some(item) => item,
27 None => return false,
28 };
29 if TokenTreeHelper(&item1) != TokenTreeHelper(&item2) {
30 return false;
31 }
32 }
33 s2.next().is_none()
34 }
35 (TokenTree::Punct(o1), TokenTree::Punct(o2)) => {
36 o1.as_char() == o2.as_char()
37 && match (o1.spacing(), o2.spacing()) {
38 (Spacing::Alone, Spacing::Alone) | (Spacing::Joint, Spacing::Joint) => true,
39 _ => false,
40 }
41 }
42 (TokenTree::Literal(l1), TokenTree::Literal(l2)) => l1.to_string() == l2.to_string(),
43 (TokenTree::Ident(s1), TokenTree::Ident(s2)) => s1 == s2,
44 _ => false,
45 }
46 }
47}
48
49impl<'a> Hash for TokenTreeHelper<'a> {
50 fn hash<H: Hasher>(&self, h: &mut H) {
51 use proc_macro2::Spacing;
52
53 match self.0 {
54 TokenTree::Group(g) => {
55 0u8.hash(h);
56 match g.delimiter() {
57 Delimiter::Parenthesis => 0u8.hash(h),
58 Delimiter::Brace => 1u8.hash(h),
59 Delimiter::Bracket => 2u8.hash(h),
60 Delimiter::None => 3u8.hash(h),
61 }
62
63 for item in g.stream() {
64 TokenTreeHelper(&item).hash(h);
65 }
66 0xffu8.hash(h); }
68 TokenTree::Punct(op) => {
69 1u8.hash(h);
70 op.as_char().hash(h);
71 match op.spacing() {
72 Spacing::Alone => 0u8.hash(h),
73 Spacing::Joint => 1u8.hash(h),
74 }
75 }
76 TokenTree::Literal(lit) => (2u8, lit.to_string()).hash(h),
77 TokenTree::Ident(word) => (3u8, word).hash(h),
78 }
79 }
80}
81
82pub struct TokenStreamHelper<'a>(pub &'a TokenStream);
83
84impl<'a> PartialEq for TokenStreamHelper<'a> {
85 fn eq(&self, other: &Self) -> bool {
86 let left = self.0.clone().into_iter().collect::<Vec<_>>();
87 let right = other.0.clone().into_iter().collect::<Vec<_>>();
88 if left.len() != right.len() {
89 return false;
90 }
91 for (a, b) in left.into_iter().zip(right) {
92 if TokenTreeHelper(&a) != TokenTreeHelper(&b) {
93 return false;
94 }
95 }
96 true
97 }
98}
99
100impl<'a> Hash for TokenStreamHelper<'a> {
101 fn hash<H: Hasher>(&self, state: &mut H) {
102 let tts = self.0.clone().into_iter().collect::<Vec<_>>();
103 tts.len().hash(state);
104 for tt in tts {
105 TokenTreeHelper(&tt).hash(state);
106 }
107 }
108}