blob: b2bdd4d8c958afb3bba83a3c0476db734ee9c50e [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0
use proc_macro::{token_stream, Group, TokenTree};
pub(crate) fn try_ident(it: &mut token_stream::IntoIter) -> Option<String> {
if let Some(TokenTree::Ident(ident)) = it.next() {
Some(ident.to_string())
} else {
None
}
}
pub(crate) fn try_literal(it: &mut token_stream::IntoIter) -> Option<String> {
if let Some(TokenTree::Literal(literal)) = it.next() {
Some(literal.to_string())
} else {
None
}
}
pub(crate) fn try_string(it: &mut token_stream::IntoIter) -> Option<String> {
try_literal(it).and_then(|string| {
if string.starts_with('\"') && string.ends_with('\"') {
let content = &string[1..string.len() - 1];
if content.contains('\\') {
panic!("Escape sequences in string literals not yet handled");
}
Some(content.to_string())
} else if string.starts_with("r\"") {
panic!("Raw string literals are not yet handled");
} else {
None
}
})
}
pub(crate) fn expect_ident(it: &mut token_stream::IntoIter) -> String {
try_ident(it).expect("Expected Ident")
}
pub(crate) fn expect_punct(it: &mut token_stream::IntoIter) -> char {
if let TokenTree::Punct(punct) = it.next().expect("Reached end of token stream for Punct") {
punct.as_char()
} else {
panic!("Expected Punct");
}
}
pub(crate) fn expect_string(it: &mut token_stream::IntoIter) -> String {
try_string(it).expect("Expected string")
}
pub(crate) fn expect_string_ascii(it: &mut token_stream::IntoIter) -> String {
let string = try_string(it).expect("Expected string");
assert!(string.is_ascii(), "Expected ASCII string");
string
}
pub(crate) fn expect_group(it: &mut token_stream::IntoIter) -> Group {
if let TokenTree::Group(group) = it.next().expect("Reached end of token stream for Group") {
group
} else {
panic!("Expected Group");
}
}
pub(crate) fn expect_end(it: &mut token_stream::IntoIter) {
if it.next().is_some() {
panic!("Expected end");
}
}