1 //! Rustc proc-macro server implementation with tt
3 //! Based on idea from https://github.com/fedochet/rust-proc-macro-expander
4 //! The lib-proc-macro server backend is `TokenStream`-agnostic, such that
5 //! we could provide any TokenStream implementation.
6 //! The original idea from fedochet is using proc-macro2 as backend,
7 //! we use tt instead for better integration with RA.
9 //! FIXME: No span and source file information is implemented yet
11 use crate::proc_macro::bridge::{self, server};
13 use std::collections::{Bound, HashMap};
15 use std::iter::FromIterator;
16 use std::str::FromStr;
17 use std::{ascii, vec::IntoIter};
19 type Group = tt::Subtree;
20 type TokenTree = tt::TokenTree;
21 type Punct = tt::Punct;
22 type Spacing = tt::Spacing;
23 type Literal = tt::Literal;
24 type Span = tt::TokenId;
26 #[derive(Debug, Clone)]
27 pub struct TokenStream {
28 pub subtree: tt::Subtree,
32 pub fn new() -> Self {
33 TokenStream { subtree: Default::default() }
36 pub fn with_subtree(subtree: tt::Subtree) -> Self {
37 TokenStream { subtree }
40 pub fn is_empty(&self) -> bool {
41 self.subtree.token_trees.is_empty()
45 /// Creates a token stream containing a single token tree.
46 impl From<TokenTree> for TokenStream {
47 fn from(tree: TokenTree) -> TokenStream {
48 TokenStream { subtree: tt::Subtree { delimiter: None, token_trees: vec![tree] } }
52 /// Collects a number of token trees into a single stream.
53 impl FromIterator<TokenTree> for TokenStream {
54 fn from_iter<I: IntoIterator<Item = TokenTree>>(trees: I) -> Self {
55 trees.into_iter().map(TokenStream::from).collect()
59 /// A "flattening" operation on token streams, collects token trees
60 /// from multiple token streams into a single stream.
61 impl FromIterator<TokenStream> for TokenStream {
62 fn from_iter<I: IntoIterator<Item = TokenStream>>(streams: I) -> Self {
63 let mut builder = TokenStreamBuilder::new();
64 streams.into_iter().for_each(|stream| builder.push(stream));
69 impl Extend<TokenTree> for TokenStream {
70 fn extend<I: IntoIterator<Item = TokenTree>>(&mut self, trees: I) {
71 self.extend(trees.into_iter().map(TokenStream::from));
75 impl Extend<TokenStream> for TokenStream {
76 fn extend<I: IntoIterator<Item = TokenStream>>(&mut self, streams: I) {
80 tt::TokenTree::Subtree(subtree) if subtree.delimiter.is_none() => {
81 self.subtree.token_trees.extend(subtree.token_trees);
84 self.subtree.token_trees.push(tkn);
92 type Level = crate::proc_macro::Level;
93 type LineColumn = crate::proc_macro::LineColumn;
94 type SourceFile = crate::proc_macro::SourceFile;
96 /// A structure representing a diagnostic message and associated children
98 #[derive(Clone, Debug)]
99 pub struct Diagnostic {
103 children: Vec<Diagnostic>,
107 /// Creates a new diagnostic with the given `level` and `message`.
108 pub fn new<T: Into<String>>(level: Level, message: T) -> Diagnostic {
109 Diagnostic { level, message: message.into(), spans: vec![], children: vec![] }
113 // Rustc Server Ident has to be `Copyable`
114 // We use a stub here for bypassing
115 #[derive(Hash, Eq, PartialEq, Copy, Clone)]
116 pub struct IdentId(u32);
118 #[derive(Clone, Hash, Eq, PartialEq)]
119 struct IdentData(tt::Ident);
122 struct IdentInterner {
123 idents: HashMap<IdentData, u32>,
124 ident_data: Vec<IdentData>,
128 fn intern(&mut self, data: &IdentData) -> u32 {
129 if let Some(index) = self.idents.get(data) {
133 let index = self.idents.len() as u32;
134 self.ident_data.push(data.clone());
135 self.idents.insert(data.clone(), index);
139 fn get(&self, index: u32) -> &IdentData {
140 &self.ident_data[index as usize]
144 fn get_mut(&mut self, index: u32) -> &mut IdentData {
145 self.ident_data.get_mut(index as usize).expect("Should be consistent")
149 pub struct TokenStreamBuilder {
153 /// Public implementation details for the `TokenStream` type, such as iterators.
154 pub mod token_stream {
155 use std::str::FromStr;
157 use super::{TokenStream, TokenTree};
159 /// An iterator over `TokenStream`'s `TokenTree`s.
160 /// The iteration is "shallow", e.g., the iterator doesn't recurse into delimited groups,
161 /// and returns whole groups as token trees.
162 impl IntoIterator for TokenStream {
163 type Item = TokenTree;
164 type IntoIter = super::IntoIter<TokenTree>;
166 fn into_iter(self) -> Self::IntoIter {
167 self.subtree.token_trees.into_iter()
171 type LexError = String;
173 /// Attempts to break the string into tokens and parse those tokens into a token stream.
174 /// May fail for a number of reasons, for example, if the string contains unbalanced delimiters
175 /// or characters not existing in the language.
176 /// All tokens in the parsed stream get `Span::call_site()` spans.
178 /// NOTE: some errors may cause panics instead of returning `LexError`. We reserve the right to
179 /// change these errors into `LexError`s later.
180 impl FromStr for TokenStream {
183 fn from_str(src: &str) -> Result<TokenStream, LexError> {
184 let (subtree, _token_map) =
185 mbe::parse_to_token_tree(src).ok_or("Failed to parse from mbe")?;
187 Ok(TokenStream { subtree })
191 impl ToString for TokenStream {
192 fn to_string(&self) -> String {
193 let tt = self.subtree.clone().into();
198 fn to_text(tkn: &tt::TokenTree) -> String {
200 tt::TokenTree::Leaf(tt::Leaf::Ident(ident)) => ident.text.clone().into(),
201 tt::TokenTree::Leaf(tt::Leaf::Literal(literal)) => literal.text.clone().into(),
202 tt::TokenTree::Leaf(tt::Leaf::Punct(punct)) => format!("{}", punct.char),
203 tt::TokenTree::Subtree(subtree) => {
204 let content = subtree
207 .fold((String::new(), true), |(last, last_to_joint), tkn| {
208 let s = [last, to_text(tkn)].join(if last_to_joint { "" } else { " " });
209 let mut is_joint = false;
210 if let tt::TokenTree::Leaf(tt::Leaf::Punct(punct)) = tkn {
211 if punct.spacing == tt::Spacing::Joint {
219 let (open, close) = match subtree.delimiter.map(|it| it.kind) {
221 Some(tt::DelimiterKind::Brace) => ("{", "}"),
222 Some(tt::DelimiterKind::Parenthesis) => ("(", ")"),
223 Some(tt::DelimiterKind::Bracket) => ("[", "]"),
225 format!("{}{}{}", open, content, close)
231 impl TokenStreamBuilder {
232 fn new() -> TokenStreamBuilder {
233 TokenStreamBuilder { acc: TokenStream::new() }
236 fn push(&mut self, stream: TokenStream) {
237 self.acc.extend(stream.into_iter())
240 fn build(self) -> TokenStream {
245 pub struct FreeFunctions;
248 pub struct TokenStreamIter {
249 trees: IntoIter<TokenTree>,
254 ident_interner: IdentInterner,
255 // FIXME: store span information here.
258 impl server::Types for Rustc {
259 type FreeFunctions = FreeFunctions;
260 type TokenStream = TokenStream;
261 type TokenStreamBuilder = TokenStreamBuilder;
262 type TokenStreamIter = TokenStreamIter;
265 type Ident = IdentId;
266 type Literal = Literal;
267 type SourceFile = SourceFile;
268 type Diagnostic = Diagnostic;
270 type MultiSpan = Vec<Span>;
273 impl server::FreeFunctions for Rustc {
274 fn track_env_var(&mut self, _var: &str, _value: Option<&str>) {
275 // FIXME: track env var accesses
276 // https://github.com/rust-lang/rust/pull/71858
280 impl server::TokenStream for Rustc {
281 fn new(&mut self) -> Self::TokenStream {
282 Self::TokenStream::new()
285 fn is_empty(&mut self, stream: &Self::TokenStream) -> bool {
288 fn from_str(&mut self, src: &str) -> Self::TokenStream {
289 Self::TokenStream::from_str(src).expect("cannot parse string")
291 fn to_string(&mut self, stream: &Self::TokenStream) -> String {
296 tree: bridge::TokenTree<Self::Group, Self::Punct, Self::Ident, Self::Literal>,
297 ) -> Self::TokenStream {
299 bridge::TokenTree::Group(group) => {
300 let tree = TokenTree::from(group);
301 Self::TokenStream::from_iter(vec![tree])
304 bridge::TokenTree::Ident(IdentId(index)) => {
305 let IdentData(ident) = self.ident_interner.get(index).clone();
306 let ident: tt::Ident = ident;
307 let leaf = tt::Leaf::from(ident);
308 let tree = TokenTree::from(leaf);
309 Self::TokenStream::from_iter(vec![tree])
312 bridge::TokenTree::Literal(literal) => {
313 let leaf = tt::Leaf::from(literal);
314 let tree = TokenTree::from(leaf);
315 Self::TokenStream::from_iter(vec![tree])
318 bridge::TokenTree::Punct(p) => {
319 let leaf = tt::Leaf::from(p);
320 let tree = TokenTree::from(leaf);
321 Self::TokenStream::from_iter(vec![tree])
326 fn into_iter(&mut self, stream: Self::TokenStream) -> Self::TokenStreamIter {
327 let trees: Vec<TokenTree> = stream.into_iter().collect();
328 TokenStreamIter { trees: trees.into_iter() }
332 impl server::TokenStreamBuilder for Rustc {
333 fn new(&mut self) -> Self::TokenStreamBuilder {
334 Self::TokenStreamBuilder::new()
336 fn push(&mut self, builder: &mut Self::TokenStreamBuilder, stream: Self::TokenStream) {
339 fn build(&mut self, builder: Self::TokenStreamBuilder) -> Self::TokenStream {
344 impl server::TokenStreamIter for Rustc {
347 iter: &mut Self::TokenStreamIter,
348 ) -> Option<bridge::TokenTree<Self::Group, Self::Punct, Self::Ident, Self::Literal>> {
349 iter.trees.next().map(|tree| match tree {
350 TokenTree::Subtree(group) => bridge::TokenTree::Group(group),
351 TokenTree::Leaf(tt::Leaf::Ident(ident)) => {
352 bridge::TokenTree::Ident(IdentId(self.ident_interner.intern(&IdentData(ident))))
354 TokenTree::Leaf(tt::Leaf::Literal(literal)) => bridge::TokenTree::Literal(literal),
355 TokenTree::Leaf(tt::Leaf::Punct(punct)) => bridge::TokenTree::Punct(punct),
360 fn delim_to_internal(d: bridge::Delimiter) -> Option<tt::Delimiter> {
362 bridge::Delimiter::Parenthesis => tt::DelimiterKind::Parenthesis,
363 bridge::Delimiter::Brace => tt::DelimiterKind::Brace,
364 bridge::Delimiter::Bracket => tt::DelimiterKind::Bracket,
365 bridge::Delimiter::None => return None,
367 Some(tt::Delimiter { id: tt::TokenId::unspecified(), kind })
370 fn delim_to_external(d: Option<tt::Delimiter>) -> bridge::Delimiter {
371 match d.map(|it| it.kind) {
372 Some(tt::DelimiterKind::Parenthesis) => bridge::Delimiter::Parenthesis,
373 Some(tt::DelimiterKind::Brace) => bridge::Delimiter::Brace,
374 Some(tt::DelimiterKind::Bracket) => bridge::Delimiter::Bracket,
375 None => bridge::Delimiter::None,
379 fn spacing_to_internal(spacing: bridge::Spacing) -> Spacing {
381 bridge::Spacing::Alone => Spacing::Alone,
382 bridge::Spacing::Joint => Spacing::Joint,
386 fn spacing_to_external(spacing: Spacing) -> bridge::Spacing {
388 Spacing::Alone => bridge::Spacing::Alone,
389 Spacing::Joint => bridge::Spacing::Joint,
393 impl server::Group for Rustc {
394 fn new(&mut self, delimiter: bridge::Delimiter, stream: Self::TokenStream) -> Self::Group {
396 delimiter: delim_to_internal(delimiter),
397 token_trees: stream.subtree.token_trees,
400 fn delimiter(&mut self, group: &Self::Group) -> bridge::Delimiter {
401 delim_to_external(group.delimiter)
404 // NOTE: Return value of do not include delimiter
405 fn stream(&mut self, group: &Self::Group) -> Self::TokenStream {
407 subtree: tt::Subtree { delimiter: None, token_trees: group.token_trees.clone() },
411 fn span(&mut self, group: &Self::Group) -> Self::Span {
412 group.delimiter.map(|it| it.id).unwrap_or_else(|| tt::TokenId::unspecified())
415 fn set_span(&mut self, _group: &mut Self::Group, _span: Self::Span) {
419 fn span_open(&mut self, _group: &Self::Group) -> Self::Span {
421 // MySpan(self.span_interner.intern(&MySpanData(group.span_open())))
422 tt::TokenId::unspecified()
425 fn span_close(&mut self, _group: &Self::Group) -> Self::Span {
427 tt::TokenId::unspecified()
431 impl server::Punct for Rustc {
432 fn new(&mut self, ch: char, spacing: bridge::Spacing) -> Self::Punct {
435 spacing: spacing_to_internal(spacing),
436 id: tt::TokenId::unspecified(),
439 fn as_char(&mut self, punct: Self::Punct) -> char {
442 fn spacing(&mut self, punct: Self::Punct) -> bridge::Spacing {
443 spacing_to_external(punct.spacing)
445 fn span(&mut self, _punct: Self::Punct) -> Self::Span {
447 tt::TokenId::unspecified()
449 fn with_span(&mut self, punct: Self::Punct, _span: Self::Span) -> Self::Punct {
455 impl server::Ident for Rustc {
456 fn new(&mut self, string: &str, _span: Self::Span, _is_raw: bool) -> Self::Ident {
458 self.ident_interner.intern(&IdentData(tt::Ident {
460 id: tt::TokenId::unspecified(),
465 fn span(&mut self, _ident: Self::Ident) -> Self::Span {
467 tt::TokenId::unspecified()
469 fn with_span(&mut self, ident: Self::Ident, _span: Self::Span) -> Self::Ident {
475 impl server::Literal for Rustc {
476 fn debug_kind(&mut self, _literal: &Self::Literal) -> String {
477 // r-a: debug_kind and suffix are unsupported; corresponding client code has been changed to not call these.
478 // They must still be present to be ABI-compatible and work with upstream proc_macro.
481 fn symbol(&mut self, literal: &Self::Literal) -> String {
482 literal.text.to_string()
484 fn suffix(&mut self, _literal: &Self::Literal) -> Option<String> {
488 fn integer(&mut self, n: &str) -> Self::Literal {
489 let n: i128 = n.parse().unwrap();
490 Literal { text: n.to_string().into(), id: tt::TokenId::unspecified() }
493 fn typed_integer(&mut self, n: &str, kind: &str) -> Self::Literal {
494 macro_rules! def_suffixed_integer {
495 ($kind:ident, $($ty:ty),*) => {
499 let n: $ty = n.parse().unwrap();
500 format!(concat!("{}", stringify!($ty)), n)
503 _ => unimplemented!("unknown args for typed_integer: n {}, kind {}", n, $kind),
509 def_suffixed_integer! {kind, u8, u16, u32, u64, u128, usize, i8, i16, i32, i64, i128};
511 Literal { text: text.into(), id: tt::TokenId::unspecified() }
514 fn float(&mut self, n: &str) -> Self::Literal {
515 let n: f64 = n.parse().unwrap();
516 let mut text = f64::to_string(&n);
517 if !text.contains('.') {
520 Literal { text: text.into(), id: tt::TokenId::unspecified() }
523 fn f32(&mut self, n: &str) -> Self::Literal {
524 let n: f32 = n.parse().unwrap();
525 let text = format!("{}f32", n);
526 Literal { text: text.into(), id: tt::TokenId::unspecified() }
529 fn f64(&mut self, n: &str) -> Self::Literal {
530 let n: f64 = n.parse().unwrap();
531 let text = format!("{}f64", n);
532 Literal { text: text.into(), id: tt::TokenId::unspecified() }
535 fn string(&mut self, string: &str) -> Self::Literal {
536 let mut escaped = String::new();
537 for ch in string.chars() {
538 escaped.extend(ch.escape_debug());
540 Literal { text: format!("\"{}\"", escaped).into(), id: tt::TokenId::unspecified() }
543 fn character(&mut self, ch: char) -> Self::Literal {
544 Literal { text: format!("'{}'", ch).into(), id: tt::TokenId::unspecified() }
547 fn byte_string(&mut self, bytes: &[u8]) -> Self::Literal {
551 .flat_map(ascii::escape_default)
552 .map(Into::<char>::into)
553 .collect::<String>();
555 Literal { text: format!("b\"{}\"", string).into(), id: tt::TokenId::unspecified() }
558 fn span(&mut self, literal: &Self::Literal) -> Self::Span {
562 fn set_span(&mut self, _literal: &mut Self::Literal, _span: Self::Span) {
568 _literal: &Self::Literal,
569 _start: Bound<usize>,
571 ) -> Option<Self::Span> {
577 impl server::SourceFile for Rustc {
578 fn eq(&mut self, file1: &Self::SourceFile, file2: &Self::SourceFile) -> bool {
581 fn path(&mut self, file: &Self::SourceFile) -> String {
583 file.path().to_str().expect("non-UTF8 file path in `proc_macro::SourceFile::path`"),
586 fn is_real(&mut self, file: &Self::SourceFile) -> bool {
591 impl server::Diagnostic for Rustc {
592 fn new(&mut self, level: Level, msg: &str, spans: Self::MultiSpan) -> Self::Diagnostic {
593 let mut diag = Diagnostic::new(level, msg);
600 _diag: &mut Self::Diagnostic,
603 _spans: Self::MultiSpan,
605 // FIXME handle diagnostic
609 fn emit(&mut self, _diag: Self::Diagnostic) {
610 // FIXME handle diagnostic
615 impl server::Span for Rustc {
616 fn debug(&mut self, span: Self::Span) -> String {
617 format!("{:?}", span.0)
619 fn def_site(&mut self) -> Self::Span {
620 // MySpan(self.span_interner.intern(&MySpanData(Span::def_site())))
622 tt::TokenId::unspecified()
624 fn call_site(&mut self) -> Self::Span {
625 // MySpan(self.span_interner.intern(&MySpanData(Span::call_site())))
627 tt::TokenId::unspecified()
629 fn source_file(&mut self, _span: Self::Span) -> Self::SourceFile {
630 // let MySpanData(span) = self.span_interner.get(span.0);
634 /// Recent feature, not yet in the proc_macro
637 /// https://github.com/rust-lang/rust/pull/55780
638 fn source_text(&mut self, _span: Self::Span) -> Option<String> {
642 fn parent(&mut self, _span: Self::Span) -> Option<Self::Span> {
646 fn source(&mut self, span: Self::Span) -> Self::Span {
650 fn start(&mut self, _span: Self::Span) -> LineColumn {
652 LineColumn { line: 0, column: 0 }
654 fn end(&mut self, _span: Self::Span) -> LineColumn {
656 LineColumn { line: 0, column: 0 }
658 fn join(&mut self, _first: Self::Span, _second: Self::Span) -> Option<Self::Span> {
661 fn resolved_at(&mut self, _span: Self::Span, _at: Self::Span) -> Self::Span {
663 tt::TokenId::unspecified()
666 fn mixed_site(&mut self) -> Self::Span {
668 tt::TokenId::unspecified()
672 impl server::MultiSpan for Rustc {
673 fn new(&mut self) -> Self::MultiSpan {
678 fn push(&mut self, other: &mut Self::MultiSpan, span: Self::Span) {
687 use crate::proc_macro::bridge::server::Literal;
690 fn test_rustc_server_literals() {
691 let mut srv = Rustc { ident_interner: IdentInterner::default() };
692 assert_eq!(srv.integer("1234").text, "1234");
694 assert_eq!(srv.typed_integer("12", "u8").text, "12u8");
695 assert_eq!(srv.typed_integer("255", "u16").text, "255u16");
696 assert_eq!(srv.typed_integer("1234", "u32").text, "1234u32");
697 assert_eq!(srv.typed_integer("15846685", "u64").text, "15846685u64");
698 assert_eq!(srv.typed_integer("15846685258", "u128").text, "15846685258u128");
699 assert_eq!(srv.typed_integer("156788984", "usize").text, "156788984usize");
700 assert_eq!(srv.typed_integer("127", "i8").text, "127i8");
701 assert_eq!(srv.typed_integer("255", "i16").text, "255i16");
702 assert_eq!(srv.typed_integer("1234", "i32").text, "1234i32");
703 assert_eq!(srv.typed_integer("15846685", "i64").text, "15846685i64");
704 assert_eq!(srv.typed_integer("15846685258", "i128").text, "15846685258i128");
705 assert_eq!(srv.float("0").text, "0.0");
706 assert_eq!(srv.float("15684.5867").text, "15684.5867");
707 assert_eq!(srv.f32("15684.58").text, "15684.58f32");
708 assert_eq!(srv.f64("15684.58").text, "15684.58f64");
710 assert_eq!(srv.string("hello_world").text, "\"hello_world\"");
711 assert_eq!(srv.character('c').text, "'c'");
712 assert_eq!(srv.byte_string(b"1234586\x88").text, "b\"1234586\\x88\"");
716 fn test_rustc_server_to_string() {
717 let s = TokenStream {
718 subtree: tt::Subtree {
721 tt::TokenTree::Leaf(tt::Leaf::Ident(tt::Ident {
722 text: "struct".into(),
723 id: tt::TokenId::unspecified(),
725 tt::TokenTree::Leaf(tt::Leaf::Ident(tt::Ident {
727 id: tt::TokenId::unspecified(),
729 tt::TokenTree::Subtree(tt::Subtree {
730 delimiter: Some(tt::Delimiter {
731 id: tt::TokenId::unspecified(),
732 kind: tt::DelimiterKind::Brace,
740 assert_eq!(s.to_string(), "struct T {}");