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-rw-r--r--third_party/rust/proc-macro2/src/wrapper.rs911
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),
+ }
+ }
+}