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::HashMap;
15 use std::iter::FromIterator;
17 use std::str::FromStr;
18 use std::{ascii, vec::IntoIter};
20 type Group = tt::Subtree;
21 type TokenTree = tt::TokenTree;
22 type Punct = tt::Punct;
23 type Spacing = tt::Spacing;
24 type Literal = tt::Literal;
25 type Span = tt::TokenId;
27 #[derive(Debug, Clone)]
28 pub struct TokenStream {
29 pub subtree: tt::Subtree,
33 pub fn new() -> Self {
34 TokenStream { subtree: Default::default() }
37 pub fn with_subtree(subtree: tt::Subtree) -> Self {
38 TokenStream { subtree }
41 pub fn is_empty(&self) -> bool {
42 self.subtree.token_trees.is_empty()
46 /// Creates a token stream containing a single token tree.
47 impl From<TokenTree> for TokenStream {
48 fn from(tree: TokenTree) -> TokenStream {
49 TokenStream { subtree: tt::Subtree { delimiter: None, token_trees: vec![tree] } }
53 /// Collects a number of token trees into a single stream.
54 impl FromIterator<TokenTree> for TokenStream {
55 fn from_iter<I: IntoIterator<Item = TokenTree>>(trees: I) -> Self {
56 trees.into_iter().map(TokenStream::from).collect()
60 /// A "flattening" operation on token streams, collects token trees
61 /// from multiple token streams into a single stream.
62 impl FromIterator<TokenStream> for TokenStream {
63 fn from_iter<I: IntoIterator<Item = TokenStream>>(streams: I) -> Self {
64 let mut builder = TokenStreamBuilder::new();
65 streams.into_iter().for_each(|stream| builder.push(stream));
70 impl Extend<TokenTree> for TokenStream {
71 fn extend<I: IntoIterator<Item = TokenTree>>(&mut self, trees: I) {
72 self.extend(trees.into_iter().map(TokenStream::from));
76 impl Extend<TokenStream> for TokenStream {
77 fn extend<I: IntoIterator<Item = TokenStream>>(&mut self, streams: I) {
81 tt::TokenTree::Subtree(subtree) if subtree.delimiter.is_none() => {
82 self.subtree.token_trees.extend(subtree.token_trees);
85 self.subtree.token_trees.push(tkn);
93 type Level = crate::proc_macro::Level;
94 type LineColumn = crate::proc_macro::LineColumn;
95 type SourceFile = crate::proc_macro::SourceFile;
97 /// A structure representing a diagnostic message and associated children
99 #[derive(Clone, Debug)]
100 pub struct Diagnostic {
104 children: Vec<Diagnostic>,
108 /// Creates a new diagnostic with the given `level` and `message`.
109 pub fn new<T: Into<String>>(level: Level, message: T) -> Diagnostic {
110 Diagnostic { level, message: message.into(), spans: vec![], children: vec![] }
114 // Rustc Server Ident has to be `Copyable`
115 // We use a stub here for bypassing
116 #[derive(Hash, Eq, PartialEq, Copy, Clone)]
117 pub struct IdentId(u32);
119 #[derive(Clone, Hash, Eq, PartialEq)]
120 struct IdentData(tt::Ident);
123 struct IdentInterner {
124 idents: HashMap<IdentData, u32>,
125 ident_data: Vec<IdentData>,
129 fn intern(&mut self, data: &IdentData) -> u32 {
130 if let Some(index) = self.idents.get(data) {
134 let index = self.idents.len() as u32;
135 self.ident_data.push(data.clone());
136 self.idents.insert(data.clone(), index);
140 fn get(&self, index: u32) -> &IdentData {
141 &self.ident_data[index as usize]
145 fn get_mut(&mut self, index: u32) -> &mut IdentData {
146 self.ident_data.get_mut(index as usize).expect("Should be consistent")
150 pub struct TokenStreamBuilder {
154 /// Public implementation details for the `TokenStream` type, such as iterators.
155 pub mod token_stream {
156 use std::str::FromStr;
158 use super::{TokenStream, TokenTree};
160 /// An iterator over `TokenStream`'s `TokenTree`s.
161 /// The iteration is "shallow", e.g., the iterator doesn't recurse into delimited groups,
162 /// and returns whole groups as token trees.
163 impl IntoIterator for TokenStream {
164 type Item = TokenTree;
165 type IntoIter = super::IntoIter<TokenTree>;
167 fn into_iter(self) -> Self::IntoIter {
168 self.subtree.token_trees.into_iter()
172 type LexError = String;
174 /// Attempts to break the string into tokens and parse those tokens into a token stream.
175 /// May fail for a number of reasons, for example, if the string contains unbalanced delimiters
176 /// or characters not existing in the language.
177 /// All tokens in the parsed stream get `Span::call_site()` spans.
179 /// NOTE: some errors may cause panics instead of returning `LexError`. We reserve the right to
180 /// change these errors into `LexError`s later.
181 impl FromStr for TokenStream {
184 fn from_str(src: &str) -> Result<TokenStream, LexError> {
185 let (subtree, _token_map) =
186 mbe::parse_to_token_tree(src).ok_or("Failed to parse from mbe")?;
188 Ok(TokenStream { subtree })
192 impl ToString for TokenStream {
193 fn to_string(&self) -> String {
194 let tt = self.subtree.clone().into();
199 fn to_text(tkn: &tt::TokenTree) -> String {
201 tt::TokenTree::Leaf(tt::Leaf::Ident(ident)) => ident.text.clone().into(),
202 tt::TokenTree::Leaf(tt::Leaf::Literal(literal)) => literal.text.clone().into(),
203 tt::TokenTree::Leaf(tt::Leaf::Punct(punct)) => format!("{}", punct.char),
204 tt::TokenTree::Subtree(subtree) => {
205 let content = subtree
208 .fold((String::new(), true), |(last, last_to_joint), tkn| {
209 let s = [last, to_text(tkn)].join(if last_to_joint { "" } else { " " });
210 let mut is_joint = false;
211 if let tt::TokenTree::Leaf(tt::Leaf::Punct(punct)) = tkn {
212 if punct.spacing == tt::Spacing::Joint {
220 let (open, close) = match subtree.delimiter.map(|it| it.kind) {
222 Some(tt::DelimiterKind::Brace) => ("{", "}"),
223 Some(tt::DelimiterKind::Parenthesis) => ("(", ")"),
224 Some(tt::DelimiterKind::Bracket) => ("[", "]"),
226 format!("{}{}{}", open, content, close)
232 impl TokenStreamBuilder {
233 fn new() -> TokenStreamBuilder {
234 TokenStreamBuilder { acc: TokenStream::new() }
237 fn push(&mut self, stream: TokenStream) {
238 self.acc.extend(stream.into_iter())
241 fn build(self) -> TokenStream {
246 pub struct FreeFunctions;
249 pub struct TokenStreamIter {
250 trees: IntoIter<TokenTree>,
255 ident_interner: IdentInterner,
256 // FIXME: store span information here.
259 impl server::Types for Rustc {
260 type FreeFunctions = FreeFunctions;
261 type TokenStream = TokenStream;
262 type TokenStreamBuilder = TokenStreamBuilder;
263 type TokenStreamIter = TokenStreamIter;
266 type Ident = IdentId;
267 type Literal = Literal;
268 type SourceFile = SourceFile;
269 type Diagnostic = Diagnostic;
271 type MultiSpan = Vec<Span>;
274 impl server::FreeFunctions for Rustc {
275 fn track_env_var(&mut self, _var: &str, _value: Option<&str>) {
276 // FIXME: track env var accesses
277 // https://github.com/rust-lang/rust/pull/71858
281 impl server::TokenStream for Rustc {
282 fn new(&mut self) -> Self::TokenStream {
283 Self::TokenStream::new()
286 fn is_empty(&mut self, stream: &Self::TokenStream) -> bool {
289 fn from_str(&mut self, src: &str) -> Self::TokenStream {
290 Self::TokenStream::from_str(src).expect("cannot parse string")
292 fn to_string(&mut self, stream: &Self::TokenStream) -> String {
297 tree: bridge::TokenTree<Self::Group, Self::Punct, Self::Ident, Self::Literal>,
298 ) -> Self::TokenStream {
300 bridge::TokenTree::Group(group) => {
301 let tree = TokenTree::from(group);
302 Self::TokenStream::from_iter(vec![tree])
305 bridge::TokenTree::Ident(IdentId(index)) => {
306 let IdentData(ident) = self.ident_interner.get(index).clone();
307 let ident: tt::Ident = ident;
308 let leaf = tt::Leaf::from(ident);
309 let tree = TokenTree::from(leaf);
310 Self::TokenStream::from_iter(vec![tree])
313 bridge::TokenTree::Literal(literal) => {
314 let leaf = tt::Leaf::from(literal);
315 let tree = TokenTree::from(leaf);
316 Self::TokenStream::from_iter(vec![tree])
319 bridge::TokenTree::Punct(p) => {
320 let leaf = tt::Leaf::from(p);
321 let tree = TokenTree::from(leaf);
322 Self::TokenStream::from_iter(vec![tree])
327 fn into_iter(&mut self, stream: Self::TokenStream) -> Self::TokenStreamIter {
328 let trees: Vec<TokenTree> = stream.into_iter().collect();
329 TokenStreamIter { trees: trees.into_iter() }
333 impl server::TokenStreamBuilder for Rustc {
334 fn new(&mut self) -> Self::TokenStreamBuilder {
335 Self::TokenStreamBuilder::new()
337 fn push(&mut self, builder: &mut Self::TokenStreamBuilder, stream: Self::TokenStream) {
340 fn build(&mut self, builder: Self::TokenStreamBuilder) -> Self::TokenStream {
345 impl server::TokenStreamIter for Rustc {
348 iter: &mut Self::TokenStreamIter,
349 ) -> Option<bridge::TokenTree<Self::Group, Self::Punct, Self::Ident, Self::Literal>> {
350 iter.trees.next().map(|tree| match tree {
351 TokenTree::Subtree(group) => bridge::TokenTree::Group(group),
352 TokenTree::Leaf(tt::Leaf::Ident(ident)) => {
353 bridge::TokenTree::Ident(IdentId(self.ident_interner.intern(&IdentData(ident))))
355 TokenTree::Leaf(tt::Leaf::Literal(literal)) => bridge::TokenTree::Literal(literal),
356 TokenTree::Leaf(tt::Leaf::Punct(punct)) => bridge::TokenTree::Punct(punct),
361 fn delim_to_internal(d: bridge::Delimiter) -> Option<tt::Delimiter> {
363 bridge::Delimiter::Parenthesis => tt::DelimiterKind::Parenthesis,
364 bridge::Delimiter::Brace => tt::DelimiterKind::Brace,
365 bridge::Delimiter::Bracket => tt::DelimiterKind::Bracket,
366 bridge::Delimiter::None => return None,
368 Some(tt::Delimiter { id: tt::TokenId::unspecified(), kind })
371 fn delim_to_external(d: Option<tt::Delimiter>) -> bridge::Delimiter {
372 match d.map(|it| it.kind) {
373 Some(tt::DelimiterKind::Parenthesis) => bridge::Delimiter::Parenthesis,
374 Some(tt::DelimiterKind::Brace) => bridge::Delimiter::Brace,
375 Some(tt::DelimiterKind::Bracket) => bridge::Delimiter::Bracket,
376 None => bridge::Delimiter::None,
380 fn spacing_to_internal(spacing: bridge::Spacing) -> Spacing {
382 bridge::Spacing::Alone => Spacing::Alone,
383 bridge::Spacing::Joint => Spacing::Joint,
387 fn spacing_to_external(spacing: Spacing) -> bridge::Spacing {
389 Spacing::Alone => bridge::Spacing::Alone,
390 Spacing::Joint => bridge::Spacing::Joint,
394 impl server::Group for Rustc {
395 fn new(&mut self, delimiter: bridge::Delimiter, stream: Self::TokenStream) -> Self::Group {
397 delimiter: delim_to_internal(delimiter),
398 token_trees: stream.subtree.token_trees,
401 fn delimiter(&mut self, group: &Self::Group) -> bridge::Delimiter {
402 delim_to_external(group.delimiter)
405 // NOTE: Return value of do not include delimiter
406 fn stream(&mut self, group: &Self::Group) -> Self::TokenStream {
408 subtree: tt::Subtree { delimiter: None, token_trees: group.token_trees.clone() },
412 fn span(&mut self, group: &Self::Group) -> Self::Span {
413 group.delimiter.map(|it| it.id).unwrap_or_else(|| tt::TokenId::unspecified())
416 fn set_span(&mut self, _group: &mut Self::Group, _span: Self::Span) {
420 fn span_open(&mut self, _group: &Self::Group) -> Self::Span {
422 // MySpan(self.span_interner.intern(&MySpanData(group.span_open())))
423 tt::TokenId::unspecified()
426 fn span_close(&mut self, _group: &Self::Group) -> Self::Span {
428 tt::TokenId::unspecified()
432 impl server::Punct for Rustc {
433 fn new(&mut self, ch: char, spacing: bridge::Spacing) -> Self::Punct {
436 spacing: spacing_to_internal(spacing),
437 id: tt::TokenId::unspecified(),
440 fn as_char(&mut self, punct: Self::Punct) -> char {
443 fn spacing(&mut self, punct: Self::Punct) -> bridge::Spacing {
444 spacing_to_external(punct.spacing)
446 fn span(&mut self, _punct: Self::Punct) -> Self::Span {
448 tt::TokenId::unspecified()
450 fn with_span(&mut self, punct: Self::Punct, _span: Self::Span) -> Self::Punct {
456 impl server::Ident for Rustc {
457 fn new(&mut self, string: &str, _span: Self::Span, _is_raw: bool) -> Self::Ident {
459 self.ident_interner.intern(&IdentData(tt::Ident {
461 id: tt::TokenId::unspecified(),
466 fn span(&mut self, _ident: Self::Ident) -> Self::Span {
468 tt::TokenId::unspecified()
470 fn with_span(&mut self, ident: Self::Ident, _span: Self::Span) -> Self::Ident {
476 impl server::Literal for Rustc {
477 fn debug_kind(&mut self, _literal: &Self::Literal) -> String {
478 // r-a: debug_kind and suffix are unsupported; corresponding client code has been changed to not call these.
479 // They must still be present to be ABI-compatible and work with upstream proc_macro.
482 fn symbol(&mut self, literal: &Self::Literal) -> String {
483 literal.text.to_string()
485 fn suffix(&mut self, _literal: &Self::Literal) -> Option<String> {
489 fn integer(&mut self, n: &str) -> Self::Literal {
490 let n: i128 = n.parse().unwrap();
491 Literal { text: n.to_string().into(), id: tt::TokenId::unspecified() }
494 fn typed_integer(&mut self, n: &str, kind: &str) -> Self::Literal {
495 macro_rules! def_suffixed_integer {
496 ($kind:ident, $($ty:ty),*) => {
500 let n: $ty = n.parse().unwrap();
501 format!(concat!("{}", stringify!($ty)), n)
504 _ => unimplemented!("unknown args for typed_integer: n {}, kind {}", n, $kind),
510 def_suffixed_integer! {kind, u8, u16, u32, u64, u128, usize, i8, i16, i32, i64, i128};
512 Literal { text: text.into(), id: tt::TokenId::unspecified() }
515 fn float(&mut self, n: &str) -> Self::Literal {
516 let n: f64 = n.parse().unwrap();
517 let mut text = f64::to_string(&n);
518 if !text.contains('.') {
521 Literal { text: text.into(), id: tt::TokenId::unspecified() }
524 fn f32(&mut self, n: &str) -> Self::Literal {
525 let n: f32 = n.parse().unwrap();
526 let text = format!("{}f32", n);
527 Literal { text: text.into(), id: tt::TokenId::unspecified() }
530 fn f64(&mut self, n: &str) -> Self::Literal {
531 let n: f64 = n.parse().unwrap();
532 let text = format!("{}f64", n);
533 Literal { text: text.into(), id: tt::TokenId::unspecified() }
536 fn string(&mut self, string: &str) -> Self::Literal {
537 let mut escaped = String::new();
538 for ch in string.chars() {
539 escaped.extend(ch.escape_debug());
541 Literal { text: format!("\"{}\"", escaped).into(), id: tt::TokenId::unspecified() }
544 fn character(&mut self, ch: char) -> Self::Literal {
545 Literal { text: format!("'{}'", ch).into(), id: tt::TokenId::unspecified() }
548 fn byte_string(&mut self, bytes: &[u8]) -> Self::Literal {
552 .flat_map(ascii::escape_default)
553 .map(Into::<char>::into)
554 .collect::<String>();
556 Literal { text: format!("b\"{}\"", string).into(), id: tt::TokenId::unspecified() }
559 fn span(&mut self, literal: &Self::Literal) -> Self::Span {
563 fn set_span(&mut self, _literal: &mut Self::Literal, _span: Self::Span) {
569 _literal: &Self::Literal,
570 _start: Bound<usize>,
572 ) -> Option<Self::Span> {
578 impl server::SourceFile for Rustc {
579 fn eq(&mut self, file1: &Self::SourceFile, file2: &Self::SourceFile) -> bool {
582 fn path(&mut self, file: &Self::SourceFile) -> String {
584 file.path().to_str().expect("non-UTF8 file path in `proc_macro::SourceFile::path`"),
587 fn is_real(&mut self, file: &Self::SourceFile) -> bool {
592 impl server::Diagnostic for Rustc {
593 fn new(&mut self, level: Level, msg: &str, spans: Self::MultiSpan) -> Self::Diagnostic {
594 let mut diag = Diagnostic::new(level, msg);
601 _diag: &mut Self::Diagnostic,
604 _spans: Self::MultiSpan,
606 // FIXME handle diagnostic
610 fn emit(&mut self, _diag: Self::Diagnostic) {
611 // FIXME handle diagnostic
616 impl server::Span for Rustc {
617 fn debug(&mut self, span: Self::Span) -> String {
618 format!("{:?}", span.0)
620 fn def_site(&mut self) -> Self::Span {
621 // MySpan(self.span_interner.intern(&MySpanData(Span::def_site())))
623 tt::TokenId::unspecified()
625 fn call_site(&mut self) -> Self::Span {
626 // MySpan(self.span_interner.intern(&MySpanData(Span::call_site())))
628 tt::TokenId::unspecified()
630 fn source_file(&mut self, _span: Self::Span) -> Self::SourceFile {
631 // let MySpanData(span) = self.span_interner.get(span.0);
635 /// Recent feature, not yet in the proc_macro
638 /// https://github.com/rust-lang/rust/pull/55780
639 fn source_text(&mut self, _span: Self::Span) -> Option<String> {
643 fn parent(&mut self, _span: Self::Span) -> Option<Self::Span> {
647 fn source(&mut self, span: Self::Span) -> Self::Span {
651 fn start(&mut self, _span: Self::Span) -> LineColumn {
653 LineColumn { line: 0, column: 0 }
655 fn end(&mut self, _span: Self::Span) -> LineColumn {
657 LineColumn { line: 0, column: 0 }
659 fn join(&mut self, _first: Self::Span, _second: Self::Span) -> Option<Self::Span> {
662 fn resolved_at(&mut self, _span: Self::Span, _at: Self::Span) -> Self::Span {
664 tt::TokenId::unspecified()
667 fn mixed_site(&mut self) -> Self::Span {
669 tt::TokenId::unspecified()
673 impl server::MultiSpan for Rustc {
674 fn new(&mut self) -> Self::MultiSpan {
679 fn push(&mut self, other: &mut Self::MultiSpan, span: Self::Span) {
688 use crate::proc_macro::bridge::server::Literal;
691 fn test_rustc_server_literals() {
692 let mut srv = Rustc { ident_interner: IdentInterner::default() };
693 assert_eq!(srv.integer("1234").text, "1234");
695 assert_eq!(srv.typed_integer("12", "u8").text, "12u8");
696 assert_eq!(srv.typed_integer("255", "u16").text, "255u16");
697 assert_eq!(srv.typed_integer("1234", "u32").text, "1234u32");
698 assert_eq!(srv.typed_integer("15846685", "u64").text, "15846685u64");
699 assert_eq!(srv.typed_integer("15846685258", "u128").text, "15846685258u128");
700 assert_eq!(srv.typed_integer("156788984", "usize").text, "156788984usize");
701 assert_eq!(srv.typed_integer("127", "i8").text, "127i8");
702 assert_eq!(srv.typed_integer("255", "i16").text, "255i16");
703 assert_eq!(srv.typed_integer("1234", "i32").text, "1234i32");
704 assert_eq!(srv.typed_integer("15846685", "i64").text, "15846685i64");
705 assert_eq!(srv.typed_integer("15846685258", "i128").text, "15846685258i128");
706 assert_eq!(srv.float("0").text, "0.0");
707 assert_eq!(srv.float("15684.5867").text, "15684.5867");
708 assert_eq!(srv.f32("15684.58").text, "15684.58f32");
709 assert_eq!(srv.f64("15684.58").text, "15684.58f64");
711 assert_eq!(srv.string("hello_world").text, "\"hello_world\"");
712 assert_eq!(srv.character('c').text, "'c'");
713 assert_eq!(srv.byte_string(b"1234586\x88").text, "b\"1234586\\x88\"");
717 fn test_rustc_server_to_string() {
718 let s = TokenStream {
719 subtree: tt::Subtree {
722 tt::TokenTree::Leaf(tt::Leaf::Ident(tt::Ident {
723 text: "struct".into(),
724 id: tt::TokenId::unspecified(),
726 tt::TokenTree::Leaf(tt::Leaf::Ident(tt::Ident {
728 id: tt::TokenId::unspecified(),
730 tt::TokenTree::Subtree(tt::Subtree {
731 delimiter: Some(tt::Delimiter {
732 id: tt::TokenId::unspecified(),
733 kind: tt::DelimiterKind::Brace,
741 assert_eq!(s.to_string(), "struct T {}");