1 // SPDX-License-Identifier: GPL-2.0
2
3 use proc_macro::{token_stream, Group, Ident, TokenStream, TokenTree};
4
try_ident(it: &mut token_stream::IntoIter) -> Option<String>5 pub(crate) fn try_ident(it: &mut token_stream::IntoIter) -> Option<String> {
6 if let Some(TokenTree::Ident(ident)) = it.next() {
7 Some(ident.to_string())
8 } else {
9 None
10 }
11 }
12
try_sign(it: &mut token_stream::IntoIter) -> Option<char>13 pub(crate) fn try_sign(it: &mut token_stream::IntoIter) -> Option<char> {
14 let peek = it.clone().next();
15 match peek {
16 Some(TokenTree::Punct(punct)) if punct.as_char() == '-' => {
17 let _ = it.next();
18 Some(punct.as_char())
19 }
20 _ => None,
21 }
22 }
23
try_literal(it: &mut token_stream::IntoIter) -> Option<String>24 pub(crate) fn try_literal(it: &mut token_stream::IntoIter) -> Option<String> {
25 if let Some(TokenTree::Literal(literal)) = it.next() {
26 Some(literal.to_string())
27 } else {
28 None
29 }
30 }
31
try_string(it: &mut token_stream::IntoIter) -> Option<String>32 pub(crate) fn try_string(it: &mut token_stream::IntoIter) -> Option<String> {
33 try_literal(it).and_then(|string| {
34 if string.starts_with('\"') && string.ends_with('\"') {
35 let content = &string[1..string.len() - 1];
36 if content.contains('\\') {
37 panic!("Escape sequences in string literals not yet handled");
38 }
39 Some(content.to_string())
40 } else if string.starts_with("r\"") {
41 panic!("Raw string literals are not yet handled");
42 } else {
43 None
44 }
45 })
46 }
47
expect_ident(it: &mut token_stream::IntoIter) -> String48 pub(crate) fn expect_ident(it: &mut token_stream::IntoIter) -> String {
49 try_ident(it).expect("Expected Ident")
50 }
51
expect_punct(it: &mut token_stream::IntoIter) -> char52 pub(crate) fn expect_punct(it: &mut token_stream::IntoIter) -> char {
53 if let TokenTree::Punct(punct) = it.next().expect("Reached end of token stream for Punct") {
54 punct.as_char()
55 } else {
56 panic!("Expected Punct");
57 }
58 }
59
expect_string(it: &mut token_stream::IntoIter) -> String60 pub(crate) fn expect_string(it: &mut token_stream::IntoIter) -> String {
61 try_string(it).expect("Expected string")
62 }
63
expect_string_ascii(it: &mut token_stream::IntoIter) -> String64 pub(crate) fn expect_string_ascii(it: &mut token_stream::IntoIter) -> String {
65 let string = try_string(it).expect("Expected string");
66 assert!(string.is_ascii(), "Expected ASCII string");
67 string
68 }
69
expect_group(it: &mut token_stream::IntoIter) -> Group70 pub(crate) fn expect_group(it: &mut token_stream::IntoIter) -> Group {
71 if let TokenTree::Group(group) = it.next().expect("Reached end of token stream for Group") {
72 group
73 } else {
74 panic!("Expected Group");
75 }
76 }
77
expect_end(it: &mut token_stream::IntoIter)78 pub(crate) fn expect_end(it: &mut token_stream::IntoIter) {
79 if it.next().is_some() {
80 panic!("Expected end");
81 }
82 }
83
84 /// Given a function declaration, finds the name of the function.
function_name(input: TokenStream) -> Option<Ident>85 pub(crate) fn function_name(input: TokenStream) -> Option<Ident> {
86 let mut input = input.into_iter();
87 while let Some(token) = input.next() {
88 match token {
89 TokenTree::Ident(i) if i.to_string() == "fn" => {
90 if let Some(TokenTree::Ident(i)) = input.next() {
91 return Some(i);
92 }
93 return None;
94 }
95 _ => continue,
96 }
97 }
98 None
99 }
100
file() -> String101 pub(crate) fn file() -> String {
102 #[cfg(not(CONFIG_RUSTC_HAS_SPAN_FILE))]
103 {
104 proc_macro::Span::call_site()
105 .source_file()
106 .path()
107 .to_string_lossy()
108 .into_owned()
109 }
110
111 #[cfg(CONFIG_RUSTC_HAS_SPAN_FILE)]
112 #[allow(clippy::incompatible_msrv)]
113 {
114 proc_macro::Span::call_site().file()
115 }
116 }
117
118 /// Parse a token stream of the form `expected_name: "value",` and return the
119 /// string in the position of "value".
120 ///
121 /// # Panics
122 ///
123 /// - On parse error.
expect_string_field(it: &mut token_stream::IntoIter, expected_name: &str) -> String124 pub(crate) fn expect_string_field(it: &mut token_stream::IntoIter, expected_name: &str) -> String {
125 assert_eq!(expect_ident(it), expected_name);
126 assert_eq!(expect_punct(it), ':');
127 let string = expect_string(it);
128 assert_eq!(expect_punct(it), ',');
129 string
130 }
131