proc_macro2/
wrapper.rs

Help
1use crate::detection::inside_proc_macro;
2use crate::fallback::{self, FromStr2 as _};
3#[cfg(span_locations)]
4use crate::location::LineColumn;
5use crate::{Delimiter, Punct, Spacing, TokenTree};
6use core::fmt::{self, Debug, Display};
7#[cfg(span_locations)]
8use core::ops::Range;
9use core::ops::RangeBounds;
10use std::ffi::CStr;
11#[cfg(super_unstable)]
12use std::path::PathBuf;
13
14#[derive(Clone)]
15pub(crate) enum TokenStream {
16    Compiler(DeferredTokenStream),
17    Fallback(fallback::TokenStream),
18}
19
20// Work around https://github.com/rust-lang/rust/issues/65080.
21// In `impl Extend<TokenTree> for TokenStream` which is used heavily by quote,
22// we hold on to the appended tokens and do proc_macro::TokenStream::extend as
23// late as possible to batch together consecutive uses of the Extend impl.
24#[derive(Clone)]
25pub(crate) struct DeferredTokenStream {
26    stream: proc_macro::TokenStream,
27    extra: Vec<proc_macro::TokenTree>,
28}
29
30pub(crate) enum LexError {
31    Compiler(proc_macro::LexError),
32    Fallback(fallback::LexError),
33
34    // Rustc was supposed to return a LexError, but it panicked instead.
35    // https://github.com/rust-lang/rust/issues/58736
36    CompilerPanic,
37}
38
39#[cold]
40fn mismatch(line: u32) -> ! {
41    #[cfg(procmacro2_backtrace)]
42    {
43        let backtrace = std::backtrace::Backtrace::force_capture();
44        panic!("compiler/fallback mismatch L{}\n\n{}", line, backtrace)
45    }
46    #[cfg(not(procmacro2_backtrace))]
47    {
48        panic!("compiler/fallback mismatch L{}", line)
49    }
50}
51
52impl DeferredTokenStream {
53    fn new(stream: proc_macro::TokenStream) -> Self {
54        DeferredTokenStream {
55            stream,
56            extra: Vec::new(),
57        }
58    }
59
60    fn is_empty(&self) -> bool {
61        self.stream.is_empty() && self.extra.is_empty()
62    }
63
64    fn evaluate_now(&mut self) {
65        // If-check provides a fast short circuit for the common case of `extra`
66        // being empty, which saves a round trip over the proc macro bridge.
67        // Improves macro expansion time in winrt by 6% in debug mode.
68        if !self.extra.is_empty() {
69            self.stream.extend(self.extra.drain(..));
70        }
71    }
72
73    fn into_token_stream(mut self) -> proc_macro::TokenStream {
74        self.evaluate_now();
75        self.stream
76    }
77}
78
79impl TokenStream {
80    pub(crate) fn new() -> Self {
81        if inside_proc_macro() {
82            TokenStream::Compiler(DeferredTokenStream::new(proc_macro::TokenStream::new()))
83        } else {
84            TokenStream::Fallback(fallback::TokenStream::new())
85        }
86    }
87
88    pub(crate) fn from_str_checked(src: &str) -> Result<Self, LexError> {
89        if inside_proc_macro() {
90            Ok(TokenStream::Compiler(DeferredTokenStream::new(
91                proc_macro::TokenStream::from_str_checked(src)?,
92            )))
93        } else {
94            Ok(TokenStream::Fallback(
95                fallback::TokenStream::from_str_checked(src)?,
96            ))
97        }
98    }
99
100    pub(crate) fn is_empty(&self) -> bool {
101        match self {
102            TokenStream::Compiler(tts) => tts.is_empty(),
103            TokenStream::Fallback(tts) => tts.is_empty(),
104        }
105    }
106
107    fn unwrap_nightly(self) -> proc_macro::TokenStream {
108        match self {
109            TokenStream::Compiler(s) => s.into_token_stream(),
110            TokenStream::Fallback(_) => mismatch(line!()),
111        }
112    }
113
114    fn unwrap_stable(self) -> fallback::TokenStream {
115        match self {
116            TokenStream::Compiler(_) => mismatch(line!()),
117            TokenStream::Fallback(s) => s,
118        }
119    }
120}
121
122impl Display for TokenStream {
123    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
124        match self {
125            TokenStream::Compiler(tts) => Display::fmt(&tts.clone().into_token_stream(), f),
126            TokenStream::Fallback(tts) => Display::fmt(tts, f),
127        }
128    }
129}
130
131impl From<proc_macro::TokenStream> for TokenStream {
132    fn from(inner: proc_macro::TokenStream) -> Self {
133        TokenStream::Compiler(DeferredTokenStream::new(inner))
134    }
135}
136
137impl From<TokenStream> for proc_macro::TokenStream {
138    fn from(inner: TokenStream) -> Self {
139        match inner {
140            TokenStream::Compiler(inner) => inner.into_token_stream(),
141            TokenStream::Fallback(inner) => {
142                proc_macro::TokenStream::from_str_unchecked(&inner.to_string())
143            }
144        }
145    }
146}
147
148impl From<fallback::TokenStream> for TokenStream {
149    fn from(inner: fallback::TokenStream) -> Self {
150        TokenStream::Fallback(inner)
151    }
152}
153
154// Assumes inside_proc_macro().
155fn into_compiler_token(token: TokenTree) -> proc_macro::TokenTree {
156    match token {
157        TokenTree::Group(tt) => proc_macro::TokenTree::Group(tt.inner.unwrap_nightly()),
158        TokenTree::Punct(tt) => {
159            let spacing = match tt.spacing() {
160                Spacing::Joint => proc_macro::Spacing::Joint,
161                Spacing::Alone => proc_macro::Spacing::Alone,
162            };
163            let mut punct = proc_macro::Punct::new(tt.as_char(), spacing);
164            punct.set_span(tt.span().inner.unwrap_nightly());
165            proc_macro::TokenTree::Punct(punct)
166        }
167        TokenTree::Ident(tt) => proc_macro::TokenTree::Ident(tt.inner.unwrap_nightly()),
168        TokenTree::Literal(tt) => proc_macro::TokenTree::Literal(tt.inner.unwrap_nightly()),
169    }
170}
171
172impl From<TokenTree> for TokenStream {
173    fn from(token: TokenTree) -> Self {
174        if inside_proc_macro() {
175            TokenStream::Compiler(DeferredTokenStream::new(proc_macro::TokenStream::from(
176                into_compiler_token(token),
177            )))
178        } else {
179            TokenStream::Fallback(fallback::TokenStream::from(token))
180        }
181    }
182}
183
184impl FromIterator<TokenTree> for TokenStream {
185    fn from_iter<I: IntoIterator<Item = TokenTree>>(trees: I) -> Self {
186        if inside_proc_macro() {
187            TokenStream::Compiler(DeferredTokenStream::new(
188                trees.into_iter().map(into_compiler_token).collect(),
189            ))
190        } else {
191            TokenStream::Fallback(trees.into_iter().collect())
192        }
193    }
194}
195
196impl FromIterator<TokenStream> for TokenStream {
197    fn from_iter<I: IntoIterator<Item = TokenStream>>(streams: I) -> Self {
198        let mut streams = streams.into_iter();
199        match streams.next() {
200            Some(TokenStream::Compiler(mut first)) => {
201                first.evaluate_now();
202                first.stream.extend(streams.map(|s| match s {
203                    TokenStream::Compiler(s) => s.into_token_stream(),
204                    TokenStream::Fallback(_) => mismatch(line!()),
205                }));
206                TokenStream::Compiler(first)
207            }
208            Some(TokenStream::Fallback(mut first)) => {
209                first.extend(streams.map(|s| match s {
210                    TokenStream::Fallback(s) => s,
211                    TokenStream::Compiler(_) => mismatch(line!()),
212                }));
213                TokenStream::Fallback(first)
214            }
215            None => TokenStream::new(),
216        }
217    }
218}
219
220impl Extend<TokenTree> for TokenStream {
221    fn extend<I: IntoIterator<Item = TokenTree>>(&mut self, stream: I) {
222        match self {
223            TokenStream::Compiler(tts) => {
224                // Here is the reason for DeferredTokenStream.
225                for token in stream {
226                    tts.extra.push(into_compiler_token(token));
227                }
228            }
229            TokenStream::Fallback(tts) => tts.extend(stream),
230        }
231    }
232}
233
234impl Extend<TokenStream> for TokenStream {
235    fn extend<I: IntoIterator<Item = TokenStream>>(&mut self, streams: I) {
236        match self {
237            TokenStream::Compiler(tts) => {
238                tts.evaluate_now();
239                tts.stream
240                    .extend(streams.into_iter().map(TokenStream::unwrap_nightly));
241            }
242            TokenStream::Fallback(tts) => {
243                tts.extend(streams.into_iter().map(TokenStream::unwrap_stable));
244            }
245        }
246    }
247}
248
249impl Debug for TokenStream {
250    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
251        match self {
252            TokenStream::Compiler(tts) => Debug::fmt(&tts.clone().into_token_stream(), f),
253            TokenStream::Fallback(tts) => Debug::fmt(tts, f),
254        }
255    }
256}
257
258impl LexError {
259    pub(crate) fn span(&self) -> Span {
260        match self {
261            LexError::Compiler(_) | LexError::CompilerPanic => Span::call_site(),
262            LexError::Fallback(e) => Span::Fallback(e.span()),
263        }
264    }
265}
266
267impl From<proc_macro::LexError> for LexError {
268    fn from(e: proc_macro::LexError) -> Self {
269        LexError::Compiler(e)
270    }
271}
272
273impl From<fallback::LexError> for LexError {
274    fn from(e: fallback::LexError) -> Self {
275        LexError::Fallback(e)
276    }
277}
278
279impl Debug for LexError {
280    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
281        match self {
282            LexError::Compiler(e) => Debug::fmt(e, f),
283            LexError::Fallback(e) => Debug::fmt(e, f),
284            LexError::CompilerPanic => {
285                let fallback = fallback::LexError::call_site();
286                Debug::fmt(&fallback, f)
287            }
288        }
289    }
290}
291
292impl Display for LexError {
293    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
294        match self {
295            LexError::Compiler(e) => Display::fmt(e, f),
296            LexError::Fallback(e) => Display::fmt(e, f),
297            LexError::CompilerPanic => {
298                let fallback = fallback::LexError::call_site();
299                Display::fmt(&fallback, f)
300            }
301        }
302    }
303}
304
305#[derive(Clone)]
306pub(crate) enum TokenTreeIter {
307    Compiler(proc_macro::token_stream::IntoIter),
308    Fallback(fallback::TokenTreeIter),
309}
310
311impl IntoIterator for TokenStream {
312    type Item = TokenTree;
313    type IntoIter = TokenTreeIter;
314
315    fn into_iter(self) -> TokenTreeIter {
316        match self {
317            TokenStream::Compiler(tts) => {
318                TokenTreeIter::Compiler(tts.into_token_stream().into_iter())
319            }
320            TokenStream::Fallback(tts) => TokenTreeIter::Fallback(tts.into_iter()),
321        }
322    }
323}
324
325impl Iterator for TokenTreeIter {
326    type Item = TokenTree;
327
328    fn next(&mut self) -> Option<TokenTree> {
329        let token = match self {
330            TokenTreeIter::Compiler(iter) => iter.next()?,
331            TokenTreeIter::Fallback(iter) => return iter.next(),
332        };
333        Some(match token {
334            proc_macro::TokenTree::Group(tt) => {
335                TokenTree::Group(crate::Group::_new(Group::Compiler(tt)))
336            }
337            proc_macro::TokenTree::Punct(tt) => {
338                let spacing = match tt.spacing() {
339                    proc_macro::Spacing::Joint => Spacing::Joint,
340                    proc_macro::Spacing::Alone => Spacing::Alone,
341                };
342                let mut o = Punct::new(tt.as_char(), spacing);
343                o.set_span(crate::Span::_new(Span::Compiler(tt.span())));
344                TokenTree::Punct(o)
345            }
346            proc_macro::TokenTree::Ident(s) => {
347                TokenTree::Ident(crate::Ident::_new(Ident::Compiler(s)))
348            }
349            proc_macro::TokenTree::Literal(l) => {
350                TokenTree::Literal(crate::Literal::_new(Literal::Compiler(l)))
351            }
352        })
353    }
354
355    fn size_hint(&self) -> (usize, Option<usize>) {
356        match self {
357            TokenTreeIter::Compiler(tts) => tts.size_hint(),
358            TokenTreeIter::Fallback(tts) => tts.size_hint(),
359        }
360    }
361}
362
363#[derive(Copy, Clone)]
364pub(crate) enum Span {
365    Compiler(proc_macro::Span),
366    Fallback(fallback::Span),
367}
368
369impl Span {
370    pub(crate) fn call_site() -> Self {
371        if inside_proc_macro() {
372            Span::Compiler(proc_macro::Span::call_site())
373        } else {
374            Span::Fallback(fallback::Span::call_site())
375        }
376    }
377
378    pub(crate) fn mixed_site() -> Self {
379        if inside_proc_macro() {
380            Span::Compiler(proc_macro::Span::mixed_site())
381        } else {
382            Span::Fallback(fallback::Span::mixed_site())
383        }
384    }
385
386    #[cfg(super_unstable)]
387    pub(crate) fn def_site() -> Self {
388        if inside_proc_macro() {
389            Span::Compiler(proc_macro::Span::def_site())
390        } else {
391            Span::Fallback(fallback::Span::def_site())
392        }
393    }
394
395    pub(crate) fn resolved_at(&self, other: Span) -> Span {
396        match (self, other) {
397            (Span::Compiler(a), Span::Compiler(b)) => Span::Compiler(a.resolved_at(b)),
398            (Span::Fallback(a), Span::Fallback(b)) => Span::Fallback(a.resolved_at(b)),
399            (Span::Compiler(_), Span::Fallback(_)) => mismatch(line!()),
400            (Span::Fallback(_), Span::Compiler(_)) => mismatch(line!()),
401        }
402    }
403
404    pub(crate) fn located_at(&self, other: Span) -> Span {
405        match (self, other) {
406            (Span::Compiler(a), Span::Compiler(b)) => Span::Compiler(a.located_at(b)),
407            (Span::Fallback(a), Span::Fallback(b)) => Span::Fallback(a.located_at(b)),
408            (Span::Compiler(_), Span::Fallback(_)) => mismatch(line!()),
409            (Span::Fallback(_), Span::Compiler(_)) => mismatch(line!()),
410        }
411    }
412
413    pub(crate) fn unwrap(self) -> proc_macro::Span {
414        match self {
415            Span::Compiler(s) => s,
416            Span::Fallback(_) => panic!("proc_macro::Span is only available in procedural macros"),
417        }
418    }
419
420    #[cfg(span_locations)]
421    pub(crate) fn byte_range(&self) -> Range<usize> {
422        match self {
423            #[cfg(proc_macro_span)]
424            Span::Compiler(s) => s.byte_range(),
425            #[cfg(not(proc_macro_span))]
426            Span::Compiler(_) => 0..0,
427            Span::Fallback(s) => s.byte_range(),
428        }
429    }
430
431    #[cfg(span_locations)]
432    pub(crate) fn start(&self) -> LineColumn {
433        match self {
434            #[cfg(proc_macro_span)]
435            Span::Compiler(s) => LineColumn {
436                line: s.line(),
437                column: s.column().saturating_sub(1),
438            },
439            #[cfg(not(proc_macro_span))]
440            Span::Compiler(_) => LineColumn { line: 0, column: 0 },
441            Span::Fallback(s) => s.start(),
442        }
443    }
444
445    #[cfg(span_locations)]
446    pub(crate) fn end(&self) -> LineColumn {
447        match self {
448            #[cfg(proc_macro_span)]
449            Span::Compiler(s) => {
450                let end = s.end();
451                LineColumn {
452                    line: end.line(),
453                    column: end.column().saturating_sub(1),
454                }
455            }
456            #[cfg(not(proc_macro_span))]
457            Span::Compiler(_) => LineColumn { line: 0, column: 0 },
458            Span::Fallback(s) => s.end(),
459        }
460    }
461
462    #[cfg(super_unstable)]
463    pub(crate) fn file(&self) -> String {
464        match self {
465            Span::Compiler(s) => s.file(),
466            Span::Fallback(s) => s.file(),
467        }
468    }
469
470    #[cfg(super_unstable)]
471    pub(crate) fn local_file(&self) -> Option<PathBuf> {
472        match self {
473            Span::Compiler(s) => s.local_file(),
474            Span::Fallback(s) => s.local_file(),
475        }
476    }
477
478    pub(crate) fn join(&self, other: Span) -> Option<Span> {
479        let ret = match (self, other) {
480            #[cfg(proc_macro_span)]
481            (Span::Compiler(a), Span::Compiler(b)) => Span::Compiler(a.join(b)?),
482            (Span::Fallback(a), Span::Fallback(b)) => Span::Fallback(a.join(b)?),
483            _ => return None,
484        };
485        Some(ret)
486    }
487
488    #[cfg(super_unstable)]
489    pub(crate) fn eq(&self, other: &Span) -> bool {
490        match (self, other) {
491            (Span::Compiler(a), Span::Compiler(b)) => a.eq(b),
492            (Span::Fallback(a), Span::Fallback(b)) => a.eq(b),
493            _ => false,
494        }
495    }
496
497    pub(crate) fn source_text(&self) -> Option<String> {
498        match self {
499            #[cfg(not(no_source_text))]
500            Span::Compiler(s) => s.source_text(),
501            #[cfg(no_source_text)]
502            Span::Compiler(_) => None,
503            Span::Fallback(s) => s.source_text(),
504        }
505    }
506
507    fn unwrap_nightly(self) -> proc_macro::Span {
508        match self {
509            Span::Compiler(s) => s,
510            Span::Fallback(_) => mismatch(line!()),
511        }
512    }
513}
514
515impl From<proc_macro::Span> for crate::Span {
516    fn from(proc_span: proc_macro::Span) -> Self {
517        crate::Span::_new(Span::Compiler(proc_span))
518    }
519}
520
521impl From<fallback::Span> for Span {
522    fn from(inner: fallback::Span) -> Self {
523        Span::Fallback(inner)
524    }
525}
526
527impl Debug for Span {
528    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
529        match self {
530            Span::Compiler(s) => Debug::fmt(s, f),
531            Span::Fallback(s) => Debug::fmt(s, f),
532        }
533    }
534}
535
536pub(crate) fn debug_span_field_if_nontrivial(debug: &mut fmt::DebugStruct, span: Span) {
537    match span {
538        Span::Compiler(s) => {
539            debug.field("span", &s);
540        }
541        Span::Fallback(s) => fallback::debug_span_field_if_nontrivial(debug, s),
542    }
543}
544
545#[derive(Clone)]
546pub(crate) enum Group {
547    Compiler(proc_macro::Group),
548    Fallback(fallback::Group),
549}
550
551impl Group {
552    pub(crate) fn new(delimiter: Delimiter, stream: TokenStream) -> Self {
553        match stream {
554            TokenStream::Compiler(tts) => {
555                let delimiter = match delimiter {
556                    Delimiter::Parenthesis => proc_macro::Delimiter::Parenthesis,
557                    Delimiter::Bracket => proc_macro::Delimiter::Bracket,
558                    Delimiter::Brace => proc_macro::Delimiter::Brace,
559                    Delimiter::None => proc_macro::Delimiter::None,
560                };
561                Group::Compiler(proc_macro::Group::new(delimiter, tts.into_token_stream()))
562            }
563            TokenStream::Fallback(stream) => {
564                Group::Fallback(fallback::Group::new(delimiter, stream))
565            }
566        }
567    }
568
569    pub(crate) fn delimiter(&self) -> Delimiter {
570        match self {
571            Group::Compiler(g) => match g.delimiter() {
572                proc_macro::Delimiter::Parenthesis => Delimiter::Parenthesis,
573                proc_macro::Delimiter::Bracket => Delimiter::Bracket,
574                proc_macro::Delimiter::Brace => Delimiter::Brace,
575                proc_macro::Delimiter::None => Delimiter::None,
576            },
577            Group::Fallback(g) => g.delimiter(),
578        }
579    }
580
581    pub(crate) fn stream(&self) -> TokenStream {
582        match self {
583            Group::Compiler(g) => TokenStream::Compiler(DeferredTokenStream::new(g.stream())),
584            Group::Fallback(g) => TokenStream::Fallback(g.stream()),
585        }
586    }
587
588    pub(crate) fn span(&self) -> Span {
589        match self {
590            Group::Compiler(g) => Span::Compiler(g.span()),
591            Group::Fallback(g) => Span::Fallback(g.span()),
592        }
593    }
594
595    pub(crate) fn span_open(&self) -> Span {
596        match self {
597            Group::Compiler(g) => Span::Compiler(g.span_open()),
598            Group::Fallback(g) => Span::Fallback(g.span_open()),
599        }
600    }
601
602    pub(crate) fn span_close(&self) -> Span {
603        match self {
604            Group::Compiler(g) => Span::Compiler(g.span_close()),
605            Group::Fallback(g) => Span::Fallback(g.span_close()),
606        }
607    }
608
609    pub(crate) fn set_span(&mut self, span: Span) {
610        match (self, span) {
611            (Group::Compiler(g), Span::Compiler(s)) => g.set_span(s),
612            (Group::Fallback(g), Span::Fallback(s)) => g.set_span(s),
613            (Group::Compiler(_), Span::Fallback(_)) => mismatch(line!()),
614            (Group::Fallback(_), Span::Compiler(_)) => mismatch(line!()),
615        }
616    }
617
618    fn unwrap_nightly(self) -> proc_macro::Group {
619        match self {
620            Group::Compiler(g) => g,
621            Group::Fallback(_) => mismatch(line!()),
622        }
623    }
624}
625
626impl From<fallback::Group> for Group {
627    fn from(g: fallback::Group) -> Self {
628        Group::Fallback(g)
629    }
630}
631
632impl Display for Group {
633    fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
634        match self {
635            Group::Compiler(group) => Display::fmt(group, formatter),
636            Group::Fallback(group) => Display::fmt(group, formatter),
637        }
638    }
639}
640
641impl Debug for Group {
642    fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
643        match self {
644            Group::Compiler(group) => Debug::fmt(group, formatter),
645            Group::Fallback(group) => Debug::fmt(group, formatter),
646        }
647    }
648}
649
650#[derive(Clone)]
651pub(crate) enum Ident {
652    Compiler(proc_macro::Ident),
653    Fallback(fallback::Ident),
654}
655
656impl Ident {
657    #[track_caller]
658    pub(crate) fn new_checked(string: &str, span: Span) -> Self {
659        match span {
660            Span::Compiler(s) => Ident::Compiler(proc_macro::Ident::new(string, s)),
661            Span::Fallback(s) => Ident::Fallback(fallback::Ident::new_checked(string, s)),
662        }
663    }
664
665    #[track_caller]
666    pub(crate) fn new_raw_checked(string: &str, span: Span) -> Self {
667        match span {
668            Span::Compiler(s) => Ident::Compiler(proc_macro::Ident::new_raw(string, s)),
669            Span::Fallback(s) => Ident::Fallback(fallback::Ident::new_raw_checked(string, s)),
670        }
671    }
672
673    pub(crate) fn span(&self) -> Span {
674        match self {
675            Ident::Compiler(t) => Span::Compiler(t.span()),
676            Ident::Fallback(t) => Span::Fallback(t.span()),
677        }
678    }
679
680    pub(crate) fn set_span(&mut self, span: Span) {
681        match (self, span) {
682            (Ident::Compiler(t), Span::Compiler(s)) => t.set_span(s),
683            (Ident::Fallback(t), Span::Fallback(s)) => t.set_span(s),
684            (Ident::Compiler(_), Span::Fallback(_)) => mismatch(line!()),
685            (Ident::Fallback(_), Span::Compiler(_)) => mismatch(line!()),
686        }
687    }
688
689    fn unwrap_nightly(self) -> proc_macro::Ident {
690        match self {
691            Ident::Compiler(s) => s,
692            Ident::Fallback(_) => mismatch(line!()),
693        }
694    }
695}
696
697impl From<fallback::Ident> for Ident {
698    fn from(inner: fallback::Ident) -> Self {
699        Ident::Fallback(inner)
700    }
701}
702
703impl PartialEq for Ident {
704    fn eq(&self, other: &Ident) -> bool {
705        match (self, other) {
706            (Ident::Compiler(t), Ident::Compiler(o)) => t.to_string() == o.to_string(),
707            (Ident::Fallback(t), Ident::Fallback(o)) => t == o,
708            (Ident::Compiler(_), Ident::Fallback(_)) => mismatch(line!()),
709            (Ident::Fallback(_), Ident::Compiler(_)) => mismatch(line!()),
710        }
711    }
712}
713
714impl<T> PartialEq<T> for Ident
715where
716    T: ?Sized + AsRef<str>,
717{
718    fn eq(&self, other: &T) -> bool {
719        let other = other.as_ref();
720        match self {
721            Ident::Compiler(t) => t.to_string() == other,
722            Ident::Fallback(t) => t == other,
723        }
724    }
725}
726
727impl Display for Ident {
728    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
729        match self {
730            Ident::Compiler(t) => Display::fmt(t, f),
731            Ident::Fallback(t) => Display::fmt(t, f),
732        }
733    }
734}
735
736impl Debug for Ident {
737    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
738        match self {
739            Ident::Compiler(t) => Debug::fmt(t, f),
740            Ident::Fallback(t) => Debug::fmt(t, f),
741        }
742    }
743}
744
745#[derive(Clone)]
746pub(crate) enum Literal {
747    Compiler(proc_macro::Literal),
748    Fallback(fallback::Literal),
749}
750
751macro_rules! suffixed_numbers {
752    ($($name:ident => $kind:ident,)*) => ($(
753        pub(crate) fn $name(n: $kind) -> Literal {
754            if inside_proc_macro() {
755                Literal::Compiler(proc_macro::Literal::$name(n))
756            } else {
757                Literal::Fallback(fallback::Literal::$name(n))
758            }
759        }
760    )*)
761}
762
763macro_rules! unsuffixed_integers {
764    ($($name:ident => $kind:ident,)*) => ($(
765        pub(crate) fn $name(n: $kind) -> Literal {
766            if inside_proc_macro() {
767                Literal::Compiler(proc_macro::Literal::$name(n))
768            } else {
769                Literal::Fallback(fallback::Literal::$name(n))
770            }
771        }
772    )*)
773}
774
775impl Literal {
776    pub(crate) fn from_str_checked(repr: &str) -> Result<Self, LexError> {
777        if inside_proc_macro() {
778            let literal = proc_macro::Literal::from_str_checked(repr)?;
779            Ok(Literal::Compiler(literal))
780        } else {
781            let literal = fallback::Literal::from_str_checked(repr)?;
782            Ok(Literal::Fallback(literal))
783        }
784    }
785
786    pub(crate) unsafe fn from_str_unchecked(repr: &str) -> Self {
787        if inside_proc_macro() {
788            Literal::Compiler(proc_macro::Literal::from_str_unchecked(repr))
789        } else {
790            Literal::Fallback(unsafe { fallback::Literal::from_str_unchecked(repr) })
791        }
792    }
793
794    suffixed_numbers! {
795        u8_suffixed => u8,
796        u16_suffixed => u16,
797        u32_suffixed => u32,
798        u64_suffixed => u64,
799        u128_suffixed => u128,
800        usize_suffixed => usize,
801        i8_suffixed => i8,
802        i16_suffixed => i16,
803        i32_suffixed => i32,
804        i64_suffixed => i64,
805        i128_suffixed => i128,
806        isize_suffixed => isize,
807
808        f32_suffixed => f32,
809        f64_suffixed => f64,
810    }
811
812    unsuffixed_integers! {
813        u8_unsuffixed => u8,
814        u16_unsuffixed => u16,
815        u32_unsuffixed => u32,
816        u64_unsuffixed => u64,
817        u128_unsuffixed => u128,
818        usize_unsuffixed => usize,
819        i8_unsuffixed => i8,
820        i16_unsuffixed => i16,
821        i32_unsuffixed => i32,
822        i64_unsuffixed => i64,
823        i128_unsuffixed => i128,
824        isize_unsuffixed => isize,
825    }
826
827    pub(crate) fn f32_unsuffixed(f: f32) -> Literal {
828        if inside_proc_macro() {
829            Literal::Compiler(proc_macro::Literal::f32_unsuffixed(f))
830        } else {
831            Literal::Fallback(fallback::Literal::f32_unsuffixed(f))
832        }
833    }
834
835    pub(crate) fn f64_unsuffixed(f: f64) -> Literal {
836        if inside_proc_macro() {
837            Literal::Compiler(proc_macro::Literal::f64_unsuffixed(f))
838        } else {
839            Literal::Fallback(fallback::Literal::f64_unsuffixed(f))
840        }
841    }
842
843    pub(crate) fn string(string: &str) -> Literal {
844        if inside_proc_macro() {
845            Literal::Compiler(proc_macro::Literal::string(string))
846        } else {
847            Literal::Fallback(fallback::Literal::string(string))
848        }
849    }
850
851    pub(crate) fn character(ch: char) -> Literal {
852        if inside_proc_macro() {
853            Literal::Compiler(proc_macro::Literal::character(ch))
854        } else {
855            Literal::Fallback(fallback::Literal::character(ch))
856        }
857    }
858
859    pub(crate) fn byte_character(byte: u8) -> Literal {
860        if inside_proc_macro() {
861            Literal::Compiler({
862                #[cfg(not(no_literal_byte_character))]
863                {
864                    proc_macro::Literal::byte_character(byte)
865                }
866
867                #[cfg(no_literal_byte_character)]
868                {
869                    let fallback = fallback::Literal::byte_character(byte);
870                    proc_macro::Literal::from_str_unchecked(&fallback.repr)
871                }
872            })
873        } else {
874            Literal::Fallback(fallback::Literal::byte_character(byte))
875        }
876    }
877
878    pub(crate) fn byte_string(bytes: &[u8]) -> Literal {
879        if inside_proc_macro() {
880            Literal::Compiler(proc_macro::Literal::byte_string(bytes))
881        } else {
882            Literal::Fallback(fallback::Literal::byte_string(bytes))
883        }
884    }
885
886    pub(crate) fn c_string(string: &CStr) -> Literal {
887        if inside_proc_macro() {
888            Literal::Compiler({
889                #[cfg(not(no_literal_c_string))]
890                {
891                    proc_macro::Literal::c_string(string)
892                }
893
894                #[cfg(no_literal_c_string)]
895                {
896                    let fallback = fallback::Literal::c_string(string);
897                    proc_macro::Literal::from_str_unchecked(&fallback.repr)
898                }
899            })
900        } else {
901            Literal::Fallback(fallback::Literal::c_string(string))
902        }
903    }
904
905    pub(crate) fn span(&self) -> Span {
906        match self {
907            Literal::Compiler(lit) => Span::Compiler(lit.span()),
908            Literal::Fallback(lit) => Span::Fallback(lit.span()),
909        }
910    }
911
912    pub(crate) fn set_span(&mut self, span: Span) {
913        match (self, span) {
914            (Literal::Compiler(lit), Span::Compiler(s)) => lit.set_span(s),
915            (Literal::Fallback(lit), Span::Fallback(s)) => lit.set_span(s),
916            (Literal::Compiler(_), Span::Fallback(_)) => mismatch(line!()),
917            (Literal::Fallback(_), Span::Compiler(_)) => mismatch(line!()),
918        }
919    }
920
921    pub(crate) fn subspan<R: RangeBounds<usize>>(&self, range: R) -> Option<Span> {
922        match self {
923            #[cfg(proc_macro_span)]
924            Literal::Compiler(lit) => lit.subspan(range).map(Span::Compiler),
925            #[cfg(not(proc_macro_span))]
926            Literal::Compiler(_lit) => None,
927            Literal::Fallback(lit) => lit.subspan(range).map(Span::Fallback),
928        }
929    }
930
931    fn unwrap_nightly(self) -> proc_macro::Literal {
932        match self {
933            Literal::Compiler(s) => s,
934            Literal::Fallback(_) => mismatch(line!()),
935        }
936    }
937}
938
939impl From<fallback::Literal> for Literal {
940    fn from(s: fallback::Literal) -> Self {
941        Literal::Fallback(s)
942    }
943}
944
945impl Display for Literal {
946    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
947        match self {
948            Literal::Compiler(t) => Display::fmt(t, f),
949            Literal::Fallback(t) => Display::fmt(t, f),
950        }
951    }
952}
953
954impl Debug for Literal {
955    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
956        match self {
957            Literal::Compiler(t) => Debug::fmt(t, f),
958            Literal::Fallback(t) => Debug::fmt(t, f),
959        }
960    }
961}
962
963#[cfg(span_locations)]
964pub(crate) fn invalidate_current_thread_spans() {
965    if inside_proc_macro() {
966        panic!(
967            "proc_macro2::extra::invalidate_current_thread_spans is not available in procedural macros"
968        );
969    } else {
970        crate::fallback::invalidate_current_thread_spans();
971    }
972}
proc_macro2/wrapper.rs

proc_macro2/
wrapper.rs
