bjoernager/rust
bjoernager/rust
1
Fork 0
Code Issues Pull requests Activity

rustc_span: Provide a reserved identifier check for a specific edition

Browse source 
Edition evaluation is kept lazy because it may be expensive.
This commit is contained in:
Vadim Petrochenkov 2020-12-21 21:59:57 +03:00
parent 11c94a1977
commit 00ff7fe6bd
1 changed files with 32 additions and 11 deletions
Download patch file Download diff file Expand all files Collapse all files

43
compiler/rustc_span/src/symbol.rs
View file

@ -13,7 +13,7 @@ use std::fmt;
use std::hash::{Hash, Hasher}; use std::hash::{Hash, Hasher};
use std::str; use std::str;
use crate::{Span, DUMMY_SP, SESSION_GLOBALS}; use crate::{Edition, Span, DUMMY_SP, SESSION_GLOBALS};
#[cfg(test)] #[cfg(test)]
mod tests; mod tests;
@ -1609,12 +1609,32 @@ pub mod sym {
} }
impl Symbol { impl Symbol {
fn is_used_keyword_2018(self) -> bool { fn is_special(self) -> bool {
self >= kw::Async && self <= kw::Dyn self <= kw::Underscore
} }
fn is_unused_keyword_2018(self) -> bool { fn is_used_keyword_always(self) -> bool {
self == kw::Try self >= kw::As && self <= kw::While
}
fn is_used_keyword_conditional(self, edition: impl FnOnce() -> Edition) -> bool {
(self >= kw::Async && self <= kw::Dyn) && edition() >= Edition::Edition2018
}
fn is_unused_keyword_always(self) -> bool {
self >= kw::Abstract && self <= kw::Yield
}
fn is_unused_keyword_conditional(self, edition: impl FnOnce() -> Edition) -> bool {
self == kw::Try && edition() >= Edition::Edition2018
}
pub fn is_reserved(self, edition: impl Copy + FnOnce() -> Edition) -> bool {
self.is_special()
|| self.is_used_keyword_always()
|| self.is_unused_keyword_always()
|| self.is_used_keyword_conditional(edition)
|| self.is_unused_keyword_conditional(edition)
} }
/// A keyword or reserved identifier that can be used as a path segment. /// A keyword or reserved identifier that can be used as a path segment.
@ -1642,26 +1662,27 @@ impl Ident {
// Returns `true` for reserved identifiers used internally for elided lifetimes, // Returns `true` for reserved identifiers used internally for elided lifetimes,
// unnamed method parameters, crate root module, error recovery etc. // unnamed method parameters, crate root module, error recovery etc.
pub fn is_special(self) -> bool { pub fn is_special(self) -> bool {
self.name <= kw::Underscore self.name.is_special()
} }
/// Returns `true` if the token is a keyword used in the language. /// Returns `true` if the token is a keyword used in the language.
pub fn is_used_keyword(self) -> bool { pub fn is_used_keyword(self) -> bool {
// Note: `span.edition()` is relatively expensive, don't call it unless necessary. // Note: `span.edition()` is relatively expensive, don't call it unless necessary.
self.name >= kw::As && self.name <= kw::While self.name.is_used_keyword_always()
|| self.name.is_used_keyword_2018() && self.span.rust_2018() || self.name.is_used_keyword_conditional(|| self.span.edition())
} }
/// Returns `true` if the token is a keyword reserved for possible future use. /// Returns `true` if the token is a keyword reserved for possible future use.
pub fn is_unused_keyword(self) -> bool { pub fn is_unused_keyword(self) -> bool {
// Note: `span.edition()` is relatively expensive, don't call it unless necessary. // Note: `span.edition()` is relatively expensive, don't call it unless necessary.
self.name >= kw::Abstract && self.name <= kw::Yield self.name.is_unused_keyword_always()
|| self.name.is_unused_keyword_2018() && self.span.rust_2018() || self.name.is_unused_keyword_conditional(|| self.span.edition())
} }
/// Returns `true` if the token is either a special identifier or a keyword. /// Returns `true` if the token is either a special identifier or a keyword.
pub fn is_reserved(self) -> bool { pub fn is_reserved(self) -> bool {
self.is_special() || self.is_used_keyword() || self.is_unused_keyword() // Note: `span.edition()` is relatively expensive, don't call it unless necessary.
self.name.is_reserved(|| self.span.edition())
} }
/// A keyword or reserved identifier that can be used as a path segment. /// A keyword or reserved identifier that can be used as a path segment.