diff options
Diffstat (limited to 'third_party/rust/proc-macro2/src/wrapper.rs')
-rw-r--r-- | third_party/rust/proc-macro2/src/wrapper.rs | 911 |
1 files changed, 911 insertions, 0 deletions
diff --git a/third_party/rust/proc-macro2/src/wrapper.rs b/third_party/rust/proc-macro2/src/wrapper.rs new file mode 100644 index 0000000000..a5d49b5e7e --- /dev/null +++ b/third_party/rust/proc-macro2/src/wrapper.rs @@ -0,0 +1,911 @@ +use crate::detection::inside_proc_macro; +#[cfg(span_locations)] +use crate::location::LineColumn; +use crate::{fallback, Delimiter, Punct, Spacing, TokenTree}; +use core::fmt::{self, Debug, Display}; +use core::ops::RangeBounds; +use core::str::FromStr; +use std::panic; +#[cfg(super_unstable)] +use std::path::PathBuf; + +#[derive(Clone)] +pub(crate) enum TokenStream { + Compiler(DeferredTokenStream), + Fallback(fallback::TokenStream), +} + +// Work around https://github.com/rust-lang/rust/issues/65080. +// In `impl Extend<TokenTree> for TokenStream` which is used heavily by quote, +// we hold on to the appended tokens and do proc_macro::TokenStream::extend as +// late as possible to batch together consecutive uses of the Extend impl. +#[derive(Clone)] +pub(crate) struct DeferredTokenStream { + stream: proc_macro::TokenStream, + extra: Vec<proc_macro::TokenTree>, +} + +pub(crate) enum LexError { + Compiler(proc_macro::LexError), + Fallback(fallback::LexError), +} + +impl LexError { + fn call_site() -> Self { + LexError::Fallback(fallback::LexError { + span: fallback::Span::call_site(), + }) + } +} + +fn mismatch() -> ! { + panic!("compiler/fallback mismatch") +} + +impl DeferredTokenStream { + fn new(stream: proc_macro::TokenStream) -> Self { + DeferredTokenStream { + stream, + extra: Vec::new(), + } + } + + fn is_empty(&self) -> bool { + self.stream.is_empty() && self.extra.is_empty() + } + + fn evaluate_now(&mut self) { + // If-check provides a fast short circuit for the common case of `extra` + // being empty, which saves a round trip over the proc macro bridge. + // Improves macro expansion time in winrt by 6% in debug mode. + if !self.extra.is_empty() { + self.stream.extend(self.extra.drain(..)); + } + } + + fn into_token_stream(mut self) -> proc_macro::TokenStream { + self.evaluate_now(); + self.stream + } +} + +impl TokenStream { + pub fn new() -> Self { + if inside_proc_macro() { + TokenStream::Compiler(DeferredTokenStream::new(proc_macro::TokenStream::new())) + } else { + TokenStream::Fallback(fallback::TokenStream::new()) + } + } + + pub fn is_empty(&self) -> bool { + match self { + TokenStream::Compiler(tts) => tts.is_empty(), + TokenStream::Fallback(tts) => tts.is_empty(), + } + } + + fn unwrap_nightly(self) -> proc_macro::TokenStream { + match self { + TokenStream::Compiler(s) => s.into_token_stream(), + TokenStream::Fallback(_) => mismatch(), + } + } + + fn unwrap_stable(self) -> fallback::TokenStream { + match self { + TokenStream::Compiler(_) => mismatch(), + TokenStream::Fallback(s) => s, + } + } +} + +impl FromStr for TokenStream { + type Err = LexError; + + fn from_str(src: &str) -> Result<TokenStream, LexError> { + if inside_proc_macro() { + Ok(TokenStream::Compiler(DeferredTokenStream::new( + proc_macro_parse(src)?, + ))) + } else { + Ok(TokenStream::Fallback(src.parse()?)) + } + } +} + +// Work around https://github.com/rust-lang/rust/issues/58736. +fn proc_macro_parse(src: &str) -> Result<proc_macro::TokenStream, LexError> { + let result = panic::catch_unwind(|| src.parse().map_err(LexError::Compiler)); + result.unwrap_or_else(|_| Err(LexError::call_site())) +} + +impl Display for TokenStream { + fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { + match self { + TokenStream::Compiler(tts) => Display::fmt(&tts.clone().into_token_stream(), f), + TokenStream::Fallback(tts) => Display::fmt(tts, f), + } + } +} + +impl From<proc_macro::TokenStream> for TokenStream { + fn from(inner: proc_macro::TokenStream) -> Self { + TokenStream::Compiler(DeferredTokenStream::new(inner)) + } +} + +impl From<TokenStream> for proc_macro::TokenStream { + fn from(inner: TokenStream) -> Self { + match inner { + TokenStream::Compiler(inner) => inner.into_token_stream(), + TokenStream::Fallback(inner) => inner.to_string().parse().unwrap(), + } + } +} + +impl From<fallback::TokenStream> for TokenStream { + fn from(inner: fallback::TokenStream) -> Self { + TokenStream::Fallback(inner) + } +} + +// Assumes inside_proc_macro(). +fn into_compiler_token(token: TokenTree) -> proc_macro::TokenTree { + match token { + TokenTree::Group(tt) => tt.inner.unwrap_nightly().into(), + TokenTree::Punct(tt) => { + let spacing = match tt.spacing() { + Spacing::Joint => proc_macro::Spacing::Joint, + Spacing::Alone => proc_macro::Spacing::Alone, + }; + let mut punct = proc_macro::Punct::new(tt.as_char(), spacing); + punct.set_span(tt.span().inner.unwrap_nightly()); + punct.into() + } + TokenTree::Ident(tt) => tt.inner.unwrap_nightly().into(), + TokenTree::Literal(tt) => tt.inner.unwrap_nightly().into(), + } +} + +impl From<TokenTree> for TokenStream { + fn from(token: TokenTree) -> Self { + if inside_proc_macro() { + TokenStream::Compiler(DeferredTokenStream::new(into_compiler_token(token).into())) + } else { + TokenStream::Fallback(token.into()) + } + } +} + +impl FromIterator<TokenTree> for TokenStream { + fn from_iter<I: IntoIterator<Item = TokenTree>>(trees: I) -> Self { + if inside_proc_macro() { + TokenStream::Compiler(DeferredTokenStream::new( + trees.into_iter().map(into_compiler_token).collect(), + )) + } else { + TokenStream::Fallback(trees.into_iter().collect()) + } + } +} + +impl FromIterator<TokenStream> for TokenStream { + fn from_iter<I: IntoIterator<Item = TokenStream>>(streams: I) -> Self { + let mut streams = streams.into_iter(); + match streams.next() { + Some(TokenStream::Compiler(mut first)) => { + first.evaluate_now(); + first.stream.extend(streams.map(|s| match s { + TokenStream::Compiler(s) => s.into_token_stream(), + TokenStream::Fallback(_) => mismatch(), + })); + TokenStream::Compiler(first) + } + Some(TokenStream::Fallback(mut first)) => { + first.extend(streams.map(|s| match s { + TokenStream::Fallback(s) => s, + TokenStream::Compiler(_) => mismatch(), + })); + TokenStream::Fallback(first) + } + None => TokenStream::new(), + } + } +} + +impl Extend<TokenTree> for TokenStream { + fn extend<I: IntoIterator<Item = TokenTree>>(&mut self, stream: I) { + match self { + TokenStream::Compiler(tts) => { + // Here is the reason for DeferredTokenStream. + for token in stream { + tts.extra.push(into_compiler_token(token)); + } + } + TokenStream::Fallback(tts) => tts.extend(stream), + } + } +} + +impl Extend<TokenStream> for TokenStream { + fn extend<I: IntoIterator<Item = TokenStream>>(&mut self, streams: I) { + match self { + TokenStream::Compiler(tts) => { + tts.evaluate_now(); + tts.stream + .extend(streams.into_iter().map(TokenStream::unwrap_nightly)); + } + TokenStream::Fallback(tts) => { + tts.extend(streams.into_iter().map(TokenStream::unwrap_stable)); + } + } + } +} + +impl Debug for TokenStream { + fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { + match self { + TokenStream::Compiler(tts) => Debug::fmt(&tts.clone().into_token_stream(), f), + TokenStream::Fallback(tts) => Debug::fmt(tts, f), + } + } +} + +impl LexError { + pub(crate) fn span(&self) -> Span { + match self { + LexError::Compiler(_) => Span::call_site(), + LexError::Fallback(e) => Span::Fallback(e.span()), + } + } +} + +impl From<proc_macro::LexError> for LexError { + fn from(e: proc_macro::LexError) -> Self { + LexError::Compiler(e) + } +} + +impl From<fallback::LexError> for LexError { + fn from(e: fallback::LexError) -> Self { + LexError::Fallback(e) + } +} + +impl Debug for LexError { + fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { + match self { + LexError::Compiler(e) => Debug::fmt(e, f), + LexError::Fallback(e) => Debug::fmt(e, f), + } + } +} + +impl Display for LexError { + fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { + match self { + LexError::Compiler(e) => Display::fmt(e, f), + LexError::Fallback(e) => Display::fmt(e, f), + } + } +} + +#[derive(Clone)] +pub(crate) enum TokenTreeIter { + Compiler(proc_macro::token_stream::IntoIter), + Fallback(fallback::TokenTreeIter), +} + +impl IntoIterator for TokenStream { + type Item = TokenTree; + type IntoIter = TokenTreeIter; + + fn into_iter(self) -> TokenTreeIter { + match self { + TokenStream::Compiler(tts) => { + TokenTreeIter::Compiler(tts.into_token_stream().into_iter()) + } + TokenStream::Fallback(tts) => TokenTreeIter::Fallback(tts.into_iter()), + } + } +} + +impl Iterator for TokenTreeIter { + type Item = TokenTree; + + fn next(&mut self) -> Option<TokenTree> { + let token = match self { + TokenTreeIter::Compiler(iter) => iter.next()?, + TokenTreeIter::Fallback(iter) => return iter.next(), + }; + Some(match token { + proc_macro::TokenTree::Group(tt) => crate::Group::_new(Group::Compiler(tt)).into(), + proc_macro::TokenTree::Punct(tt) => { + let spacing = match tt.spacing() { + proc_macro::Spacing::Joint => Spacing::Joint, + proc_macro::Spacing::Alone => Spacing::Alone, + }; + let mut o = Punct::new(tt.as_char(), spacing); + o.set_span(crate::Span::_new(Span::Compiler(tt.span()))); + o.into() + } + proc_macro::TokenTree::Ident(s) => crate::Ident::_new(Ident::Compiler(s)).into(), + proc_macro::TokenTree::Literal(l) => crate::Literal::_new(Literal::Compiler(l)).into(), + }) + } + + fn size_hint(&self) -> (usize, Option<usize>) { + match self { + TokenTreeIter::Compiler(tts) => tts.size_hint(), + TokenTreeIter::Fallback(tts) => tts.size_hint(), + } + } +} + +#[derive(Clone, PartialEq, Eq)] +#[cfg(super_unstable)] +pub(crate) enum SourceFile { + Compiler(proc_macro::SourceFile), + Fallback(fallback::SourceFile), +} + +#[cfg(super_unstable)] +impl SourceFile { + fn nightly(sf: proc_macro::SourceFile) -> Self { + SourceFile::Compiler(sf) + } + + /// Get the path to this source file as a string. + pub fn path(&self) -> PathBuf { + match self { + SourceFile::Compiler(a) => a.path(), + SourceFile::Fallback(a) => a.path(), + } + } + + pub fn is_real(&self) -> bool { + match self { + SourceFile::Compiler(a) => a.is_real(), + SourceFile::Fallback(a) => a.is_real(), + } + } +} + +#[cfg(super_unstable)] +impl Debug for SourceFile { + fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { + match self { + SourceFile::Compiler(a) => Debug::fmt(a, f), + SourceFile::Fallback(a) => Debug::fmt(a, f), + } + } +} + +#[derive(Copy, Clone)] +pub(crate) enum Span { + Compiler(proc_macro::Span), + Fallback(fallback::Span), +} + +impl Span { + pub fn call_site() -> Self { + if inside_proc_macro() { + Span::Compiler(proc_macro::Span::call_site()) + } else { + Span::Fallback(fallback::Span::call_site()) + } + } + + pub fn mixed_site() -> Self { + if inside_proc_macro() { + Span::Compiler(proc_macro::Span::mixed_site()) + } else { + Span::Fallback(fallback::Span::mixed_site()) + } + } + + #[cfg(super_unstable)] + pub fn def_site() -> Self { + if inside_proc_macro() { + Span::Compiler(proc_macro::Span::def_site()) + } else { + Span::Fallback(fallback::Span::def_site()) + } + } + + pub fn resolved_at(&self, other: Span) -> Span { + match (self, other) { + (Span::Compiler(a), Span::Compiler(b)) => Span::Compiler(a.resolved_at(b)), + (Span::Fallback(a), Span::Fallback(b)) => Span::Fallback(a.resolved_at(b)), + _ => mismatch(), + } + } + + pub fn located_at(&self, other: Span) -> Span { + match (self, other) { + (Span::Compiler(a), Span::Compiler(b)) => Span::Compiler(a.located_at(b)), + (Span::Fallback(a), Span::Fallback(b)) => Span::Fallback(a.located_at(b)), + _ => mismatch(), + } + } + + pub fn unwrap(self) -> proc_macro::Span { + match self { + Span::Compiler(s) => s, + Span::Fallback(_) => panic!("proc_macro::Span is only available in procedural macros"), + } + } + + #[cfg(super_unstable)] + pub fn source_file(&self) -> SourceFile { + match self { + Span::Compiler(s) => SourceFile::nightly(s.source_file()), + Span::Fallback(s) => SourceFile::Fallback(s.source_file()), + } + } + + #[cfg(span_locations)] + pub fn start(&self) -> LineColumn { + match self { + Span::Compiler(_) => LineColumn { line: 0, column: 0 }, + Span::Fallback(s) => s.start(), + } + } + + #[cfg(span_locations)] + pub fn end(&self) -> LineColumn { + match self { + Span::Compiler(_) => LineColumn { line: 0, column: 0 }, + Span::Fallback(s) => s.end(), + } + } + + pub fn join(&self, other: Span) -> Option<Span> { + let ret = match (self, other) { + #[cfg(proc_macro_span)] + (Span::Compiler(a), Span::Compiler(b)) => Span::Compiler(a.join(b)?), + (Span::Fallback(a), Span::Fallback(b)) => Span::Fallback(a.join(b)?), + _ => return None, + }; + Some(ret) + } + + #[cfg(super_unstable)] + pub fn eq(&self, other: &Span) -> bool { + match (self, other) { + (Span::Compiler(a), Span::Compiler(b)) => a.eq(b), + (Span::Fallback(a), Span::Fallback(b)) => a.eq(b), + _ => false, + } + } + + pub fn source_text(&self) -> Option<String> { + match self { + #[cfg(not(no_source_text))] + Span::Compiler(s) => s.source_text(), + #[cfg(no_source_text)] + Span::Compiler(_) => None, + Span::Fallback(s) => s.source_text(), + } + } + + fn unwrap_nightly(self) -> proc_macro::Span { + match self { + Span::Compiler(s) => s, + Span::Fallback(_) => mismatch(), + } + } +} + +impl From<proc_macro::Span> for crate::Span { + fn from(proc_span: proc_macro::Span) -> Self { + crate::Span::_new(Span::Compiler(proc_span)) + } +} + +impl From<fallback::Span> for Span { + fn from(inner: fallback::Span) -> Self { + Span::Fallback(inner) + } +} + +impl Debug for Span { + fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { + match self { + Span::Compiler(s) => Debug::fmt(s, f), + Span::Fallback(s) => Debug::fmt(s, f), + } + } +} + +pub(crate) fn debug_span_field_if_nontrivial(debug: &mut fmt::DebugStruct, span: Span) { + match span { + Span::Compiler(s) => { + debug.field("span", &s); + } + Span::Fallback(s) => fallback::debug_span_field_if_nontrivial(debug, s), + } +} + +#[derive(Clone)] +pub(crate) enum Group { + Compiler(proc_macro::Group), + Fallback(fallback::Group), +} + +impl Group { + pub fn new(delimiter: Delimiter, stream: TokenStream) -> Self { + match stream { + TokenStream::Compiler(tts) => { + let delimiter = match delimiter { + Delimiter::Parenthesis => proc_macro::Delimiter::Parenthesis, + Delimiter::Bracket => proc_macro::Delimiter::Bracket, + Delimiter::Brace => proc_macro::Delimiter::Brace, + Delimiter::None => proc_macro::Delimiter::None, + }; + Group::Compiler(proc_macro::Group::new(delimiter, tts.into_token_stream())) + } + TokenStream::Fallback(stream) => { + Group::Fallback(fallback::Group::new(delimiter, stream)) + } + } + } + + pub fn delimiter(&self) -> Delimiter { + match self { + Group::Compiler(g) => match g.delimiter() { + proc_macro::Delimiter::Parenthesis => Delimiter::Parenthesis, + proc_macro::Delimiter::Bracket => Delimiter::Bracket, + proc_macro::Delimiter::Brace => Delimiter::Brace, + proc_macro::Delimiter::None => Delimiter::None, + }, + Group::Fallback(g) => g.delimiter(), + } + } + + pub fn stream(&self) -> TokenStream { + match self { + Group::Compiler(g) => TokenStream::Compiler(DeferredTokenStream::new(g.stream())), + Group::Fallback(g) => TokenStream::Fallback(g.stream()), + } + } + + pub fn span(&self) -> Span { + match self { + Group::Compiler(g) => Span::Compiler(g.span()), + Group::Fallback(g) => Span::Fallback(g.span()), + } + } + + pub fn span_open(&self) -> Span { + match self { + Group::Compiler(g) => Span::Compiler(g.span_open()), + Group::Fallback(g) => Span::Fallback(g.span_open()), + } + } + + pub fn span_close(&self) -> Span { + match self { + Group::Compiler(g) => Span::Compiler(g.span_close()), + Group::Fallback(g) => Span::Fallback(g.span_close()), + } + } + + pub fn set_span(&mut self, span: Span) { + match (self, span) { + (Group::Compiler(g), Span::Compiler(s)) => g.set_span(s), + (Group::Fallback(g), Span::Fallback(s)) => g.set_span(s), + _ => mismatch(), + } + } + + fn unwrap_nightly(self) -> proc_macro::Group { + match self { + Group::Compiler(g) => g, + Group::Fallback(_) => mismatch(), + } + } +} + +impl From<fallback::Group> for Group { + fn from(g: fallback::Group) -> Self { + Group::Fallback(g) + } +} + +impl Display for Group { + fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result { + match self { + Group::Compiler(group) => Display::fmt(group, formatter), + Group::Fallback(group) => Display::fmt(group, formatter), + } + } +} + +impl Debug for Group { + fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result { + match self { + Group::Compiler(group) => Debug::fmt(group, formatter), + Group::Fallback(group) => Debug::fmt(group, formatter), + } + } +} + +#[derive(Clone)] +pub(crate) enum Ident { + Compiler(proc_macro::Ident), + Fallback(fallback::Ident), +} + +impl Ident { + #[track_caller] + pub fn new_checked(string: &str, span: Span) -> Self { + match span { + Span::Compiler(s) => Ident::Compiler(proc_macro::Ident::new(string, s)), + Span::Fallback(s) => Ident::Fallback(fallback::Ident::new_checked(string, s)), + } + } + + pub fn new_unchecked(string: &str, span: fallback::Span) -> Self { + Ident::Fallback(fallback::Ident::new_unchecked(string, span)) + } + + #[track_caller] + pub fn new_raw_checked(string: &str, span: Span) -> Self { + match span { + Span::Compiler(s) => Ident::Compiler(proc_macro::Ident::new_raw(string, s)), + Span::Fallback(s) => Ident::Fallback(fallback::Ident::new_raw_checked(string, s)), + } + } + + pub fn new_raw_unchecked(string: &str, span: fallback::Span) -> Self { + Ident::Fallback(fallback::Ident::new_raw_unchecked(string, span)) + } + + pub fn span(&self) -> Span { + match self { + Ident::Compiler(t) => Span::Compiler(t.span()), + Ident::Fallback(t) => Span::Fallback(t.span()), + } + } + + pub fn set_span(&mut self, span: Span) { + match (self, span) { + (Ident::Compiler(t), Span::Compiler(s)) => t.set_span(s), + (Ident::Fallback(t), Span::Fallback(s)) => t.set_span(s), + _ => mismatch(), + } + } + + fn unwrap_nightly(self) -> proc_macro::Ident { + match self { + Ident::Compiler(s) => s, + Ident::Fallback(_) => mismatch(), + } + } +} + +impl PartialEq for Ident { + fn eq(&self, other: &Ident) -> bool { + match (self, other) { + (Ident::Compiler(t), Ident::Compiler(o)) => t.to_string() == o.to_string(), + (Ident::Fallback(t), Ident::Fallback(o)) => t == o, + _ => mismatch(), + } + } +} + +impl<T> PartialEq<T> for Ident +where + T: ?Sized + AsRef<str>, +{ + fn eq(&self, other: &T) -> bool { + let other = other.as_ref(); + match self { + Ident::Compiler(t) => t.to_string() == other, + Ident::Fallback(t) => t == other, + } + } +} + +impl Display for Ident { + fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { + match self { + Ident::Compiler(t) => Display::fmt(t, f), + Ident::Fallback(t) => Display::fmt(t, f), + } + } +} + +impl Debug for Ident { + fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { + match self { + Ident::Compiler(t) => Debug::fmt(t, f), + Ident::Fallback(t) => Debug::fmt(t, f), + } + } +} + +#[derive(Clone)] +pub(crate) enum Literal { + Compiler(proc_macro::Literal), + Fallback(fallback::Literal), +} + +macro_rules! suffixed_numbers { + ($($name:ident => $kind:ident,)*) => ($( + pub fn $name(n: $kind) -> Literal { + if inside_proc_macro() { + Literal::Compiler(proc_macro::Literal::$name(n)) + } else { + Literal::Fallback(fallback::Literal::$name(n)) + } + } + )*) +} + +macro_rules! unsuffixed_integers { + ($($name:ident => $kind:ident,)*) => ($( + pub fn $name(n: $kind) -> Literal { + if inside_proc_macro() { + Literal::Compiler(proc_macro::Literal::$name(n)) + } else { + Literal::Fallback(fallback::Literal::$name(n)) + } + } + )*) +} + +impl Literal { + pub unsafe fn from_str_unchecked(repr: &str) -> Self { + if inside_proc_macro() { + Literal::Compiler(proc_macro::Literal::from_str(repr).expect("invalid literal")) + } else { + Literal::Fallback(unsafe { fallback::Literal::from_str_unchecked(repr) }) + } + } + + suffixed_numbers! { + u8_suffixed => u8, + u16_suffixed => u16, + u32_suffixed => u32, + u64_suffixed => u64, + u128_suffixed => u128, + usize_suffixed => usize, + i8_suffixed => i8, + i16_suffixed => i16, + i32_suffixed => i32, + i64_suffixed => i64, + i128_suffixed => i128, + isize_suffixed => isize, + + f32_suffixed => f32, + f64_suffixed => f64, + } + + unsuffixed_integers! { + u8_unsuffixed => u8, + u16_unsuffixed => u16, + u32_unsuffixed => u32, + u64_unsuffixed => u64, + u128_unsuffixed => u128, + usize_unsuffixed => usize, + i8_unsuffixed => i8, + i16_unsuffixed => i16, + i32_unsuffixed => i32, + i64_unsuffixed => i64, + i128_unsuffixed => i128, + isize_unsuffixed => isize, + } + + pub fn f32_unsuffixed(f: f32) -> Literal { + if inside_proc_macro() { + Literal::Compiler(proc_macro::Literal::f32_unsuffixed(f)) + } else { + Literal::Fallback(fallback::Literal::f32_unsuffixed(f)) + } + } + + pub fn f64_unsuffixed(f: f64) -> Literal { + if inside_proc_macro() { + Literal::Compiler(proc_macro::Literal::f64_unsuffixed(f)) + } else { + Literal::Fallback(fallback::Literal::f64_unsuffixed(f)) + } + } + + pub fn string(t: &str) -> Literal { + if inside_proc_macro() { + Literal::Compiler(proc_macro::Literal::string(t)) + } else { + Literal::Fallback(fallback::Literal::string(t)) + } + } + + pub fn character(t: char) -> Literal { + if inside_proc_macro() { + Literal::Compiler(proc_macro::Literal::character(t)) + } else { + Literal::Fallback(fallback::Literal::character(t)) + } + } + + pub fn byte_string(bytes: &[u8]) -> Literal { + if inside_proc_macro() { + Literal::Compiler(proc_macro::Literal::byte_string(bytes)) + } else { + Literal::Fallback(fallback::Literal::byte_string(bytes)) + } + } + + pub fn span(&self) -> Span { + match self { + Literal::Compiler(lit) => Span::Compiler(lit.span()), + Literal::Fallback(lit) => Span::Fallback(lit.span()), + } + } + + pub fn set_span(&mut self, span: Span) { + match (self, span) { + (Literal::Compiler(lit), Span::Compiler(s)) => lit.set_span(s), + (Literal::Fallback(lit), Span::Fallback(s)) => lit.set_span(s), + _ => mismatch(), + } + } + + pub fn subspan<R: RangeBounds<usize>>(&self, range: R) -> Option<Span> { + match self { + #[cfg(proc_macro_span)] + Literal::Compiler(lit) => lit.subspan(range).map(Span::Compiler), + #[cfg(not(proc_macro_span))] + Literal::Compiler(_lit) => None, + Literal::Fallback(lit) => lit.subspan(range).map(Span::Fallback), + } + } + + fn unwrap_nightly(self) -> proc_macro::Literal { + match self { + Literal::Compiler(s) => s, + Literal::Fallback(_) => mismatch(), + } + } +} + +impl From<fallback::Literal> for Literal { + fn from(s: fallback::Literal) -> Self { + Literal::Fallback(s) + } +} + +impl FromStr for Literal { + type Err = LexError; + + fn from_str(repr: &str) -> Result<Self, Self::Err> { + if inside_proc_macro() { + let literal = proc_macro::Literal::from_str(repr)?; + Ok(Literal::Compiler(literal)) + } else { + let literal = fallback::Literal::from_str(repr)?; + Ok(Literal::Fallback(literal)) + } + } +} + +impl Display for Literal { + fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { + match self { + Literal::Compiler(t) => Display::fmt(t, f), + Literal::Fallback(t) => Display::fmt(t, f), + } + } +} + +impl Debug for Literal { + fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { + match self { + Literal::Compiler(t) => Debug::fmt(t, f), + Literal::Fallback(t) => Debug::fmt(t, f), + } + } +} |