aboutsummaryrefslogtreecommitdiff
path: root/crates/mbe
diff options
context:
space:
mode:
Diffstat (limited to 'crates/mbe')
-rw-r--r--crates/mbe/Cargo.toml21
-rw-r--r--crates/mbe/src/lib.rs278
-rw-r--r--crates/mbe/src/mbe_expander.rs180
-rw-r--r--crates/mbe/src/mbe_expander/matcher.rs477
-rw-r--r--crates/mbe/src/mbe_expander/transcriber.rs254
-rw-r--r--crates/mbe/src/parser.rs184
-rw-r--r--crates/mbe/src/subtree_source.rs197
-rw-r--r--crates/mbe/src/syntax_bridge.rs832
-rw-r--r--crates/mbe/src/tests.rs1898
-rw-r--r--crates/mbe/src/tt_iter.rs75
10 files changed, 4396 insertions, 0 deletions
diff --git a/crates/mbe/Cargo.toml b/crates/mbe/Cargo.toml
new file mode 100644
index 000000000..1aba8b7c4
--- /dev/null
+++ b/crates/mbe/Cargo.toml
@@ -0,0 +1,21 @@
1[package]
2name = "mbe"
3version = "0.0.0"
4license = "MIT OR Apache-2.0"
5authors = ["rust-analyzer developers"]
6edition = "2018"
7
8[lib]
9doctest = false
10
11[dependencies]
12rustc-hash = "1.1.0"
13smallvec = "1.2.0"
14log = "0.4.8"
15
16syntax = { path = "../syntax" }
17parser = { path = "../parser" }
18tt = { path = "../tt" }
19
20[dev-dependencies]
21test_utils = { path = "../test_utils" }
diff --git a/crates/mbe/src/lib.rs b/crates/mbe/src/lib.rs
new file mode 100644
index 000000000..f854ca09a
--- /dev/null
+++ b/crates/mbe/src/lib.rs
@@ -0,0 +1,278 @@
1//! `mbe` (short for Macro By Example) crate contains code for handling
2//! `macro_rules` macros. It uses `TokenTree` (from `tt` package) as the
3//! interface, although it contains some code to bridge `SyntaxNode`s and
4//! `TokenTree`s as well!
5
6mod parser;
7mod mbe_expander;
8mod syntax_bridge;
9mod tt_iter;
10mod subtree_source;
11
12#[cfg(test)]
13mod tests;
14
15pub use tt::{Delimiter, Punct};
16
17use crate::{
18 parser::{parse_pattern, Op},
19 tt_iter::TtIter,
20};
21
22#[derive(Debug, PartialEq, Eq)]
23pub enum ParseError {
24 Expected(String),
25 RepetitionEmtpyTokenTree,
26}
27
28#[derive(Debug, PartialEq, Eq, Clone)]
29pub enum ExpandError {
30 NoMatchingRule,
31 UnexpectedToken,
32 BindingError(String),
33 ConversionError,
34 InvalidRepeat,
35 ProcMacroError(tt::ExpansionError),
36}
37
38impl From<tt::ExpansionError> for ExpandError {
39 fn from(it: tt::ExpansionError) -> Self {
40 ExpandError::ProcMacroError(it)
41 }
42}
43
44pub use crate::syntax_bridge::{
45 ast_to_token_tree, parse_to_token_tree, syntax_node_to_token_tree, token_tree_to_syntax_node,
46 TokenMap,
47};
48
49/// This struct contains AST for a single `macro_rules` definition. What might
50/// be very confusing is that AST has almost exactly the same shape as
51/// `tt::TokenTree`, but there's a crucial difference: in macro rules, `$ident`
52/// and `$()*` have special meaning (see `Var` and `Repeat` data structures)
53#[derive(Clone, Debug, PartialEq, Eq)]
54pub struct MacroRules {
55 rules: Vec<Rule>,
56 /// Highest id of the token we have in TokenMap
57 shift: Shift,
58}
59
60#[derive(Clone, Debug, PartialEq, Eq)]
61struct Rule {
62 lhs: tt::Subtree,
63 rhs: tt::Subtree,
64}
65
66#[derive(Clone, Copy, Debug, PartialEq, Eq)]
67struct Shift(u32);
68
69impl Shift {
70 fn new(tt: &tt::Subtree) -> Shift {
71 // Note that TokenId is started from zero,
72 // We have to add 1 to prevent duplication.
73 let value = max_id(tt).map_or(0, |it| it + 1);
74 return Shift(value);
75
76 // Find the max token id inside a subtree
77 fn max_id(subtree: &tt::Subtree) -> Option<u32> {
78 subtree
79 .token_trees
80 .iter()
81 .filter_map(|tt| match tt {
82 tt::TokenTree::Subtree(subtree) => {
83 let tree_id = max_id(subtree);
84 match subtree.delimiter {
85 Some(it) if it.id != tt::TokenId::unspecified() => {
86 Some(tree_id.map_or(it.id.0, |t| t.max(it.id.0)))
87 }
88 _ => tree_id,
89 }
90 }
91 tt::TokenTree::Leaf(tt::Leaf::Ident(ident))
92 if ident.id != tt::TokenId::unspecified() =>
93 {
94 Some(ident.id.0)
95 }
96 _ => None,
97 })
98 .max()
99 }
100 }
101
102 /// Shift given TokenTree token id
103 fn shift_all(self, tt: &mut tt::Subtree) {
104 for t in tt.token_trees.iter_mut() {
105 match t {
106 tt::TokenTree::Leaf(leaf) => match leaf {
107 tt::Leaf::Ident(ident) => ident.id = self.shift(ident.id),
108 tt::Leaf::Punct(punct) => punct.id = self.shift(punct.id),
109 tt::Leaf::Literal(lit) => lit.id = self.shift(lit.id),
110 },
111 tt::TokenTree::Subtree(tt) => {
112 if let Some(it) = tt.delimiter.as_mut() {
113 it.id = self.shift(it.id);
114 };
115 self.shift_all(tt)
116 }
117 }
118 }
119 }
120
121 fn shift(self, id: tt::TokenId) -> tt::TokenId {
122 if id == tt::TokenId::unspecified() {
123 return id;
124 }
125 tt::TokenId(id.0 + self.0)
126 }
127
128 fn unshift(self, id: tt::TokenId) -> Option<tt::TokenId> {
129 id.0.checked_sub(self.0).map(tt::TokenId)
130 }
131}
132
133#[derive(Debug, Eq, PartialEq)]
134pub enum Origin {
135 Def,
136 Call,
137}
138
139impl MacroRules {
140 pub fn parse(tt: &tt::Subtree) -> Result<MacroRules, ParseError> {
141 // Note: this parsing can be implemented using mbe machinery itself, by
142 // matching against `$($lhs:tt => $rhs:tt);*` pattern, but implementing
143 // manually seems easier.
144 let mut src = TtIter::new(tt);
145 let mut rules = Vec::new();
146 while src.len() > 0 {
147 let rule = Rule::parse(&mut src)?;
148 rules.push(rule);
149 if let Err(()) = src.expect_char(';') {
150 if src.len() > 0 {
151 return Err(ParseError::Expected("expected `:`".to_string()));
152 }
153 break;
154 }
155 }
156
157 for rule in rules.iter() {
158 validate(&rule.lhs)?;
159 }
160
161 Ok(MacroRules { rules, shift: Shift::new(tt) })
162 }
163
164 pub fn expand(&self, tt: &tt::Subtree) -> ExpandResult<tt::Subtree> {
165 // apply shift
166 let mut tt = tt.clone();
167 self.shift.shift_all(&mut tt);
168 mbe_expander::expand(self, &tt)
169 }
170
171 pub fn map_id_down(&self, id: tt::TokenId) -> tt::TokenId {
172 self.shift.shift(id)
173 }
174
175 pub fn map_id_up(&self, id: tt::TokenId) -> (tt::TokenId, Origin) {
176 match self.shift.unshift(id) {
177 Some(id) => (id, Origin::Call),
178 None => (id, Origin::Def),
179 }
180 }
181}
182
183impl Rule {
184 fn parse(src: &mut TtIter) -> Result<Rule, ParseError> {
185 let mut lhs = src
186 .expect_subtree()
187 .map_err(|()| ParseError::Expected("expected subtree".to_string()))?
188 .clone();
189 lhs.delimiter = None;
190 src.expect_char('=').map_err(|()| ParseError::Expected("expected `=`".to_string()))?;
191 src.expect_char('>').map_err(|()| ParseError::Expected("expected `>`".to_string()))?;
192 let mut rhs = src
193 .expect_subtree()
194 .map_err(|()| ParseError::Expected("expected subtree".to_string()))?
195 .clone();
196 rhs.delimiter = None;
197 Ok(crate::Rule { lhs, rhs })
198 }
199}
200
201fn to_parse_error(e: ExpandError) -> ParseError {
202 let msg = match e {
203 ExpandError::InvalidRepeat => "invalid repeat".to_string(),
204 _ => "invalid macro definition".to_string(),
205 };
206 ParseError::Expected(msg)
207}
208
209fn validate(pattern: &tt::Subtree) -> Result<(), ParseError> {
210 for op in parse_pattern(pattern) {
211 let op = op.map_err(to_parse_error)?;
212
213 match op {
214 Op::TokenTree(tt::TokenTree::Subtree(subtree)) => validate(subtree)?,
215 Op::Repeat { subtree, separator, .. } => {
216 // Checks that no repetition which could match an empty token
217 // https://github.com/rust-lang/rust/blob/a58b1ed44f5e06976de2bdc4d7dc81c36a96934f/src/librustc_expand/mbe/macro_rules.rs#L558
218
219 if separator.is_none() {
220 if parse_pattern(subtree).all(|child_op| {
221 match child_op.map_err(to_parse_error) {
222 Ok(Op::Var { kind, .. }) => {
223 // vis is optional
224 if kind.map_or(false, |it| it == "vis") {
225 return true;
226 }
227 }
228 Ok(Op::Repeat { kind, .. }) => {
229 return matches!(
230 kind,
231 parser::RepeatKind::ZeroOrMore | parser::RepeatKind::ZeroOrOne
232 )
233 }
234 _ => {}
235 }
236 false
237 }) {
238 return Err(ParseError::RepetitionEmtpyTokenTree);
239 }
240 }
241 validate(subtree)?
242 }
243 _ => (),
244 }
245 }
246 Ok(())
247}
248
249#[derive(Debug)]
250pub struct ExpandResult<T>(pub T, pub Option<ExpandError>);
251
252impl<T> ExpandResult<T> {
253 pub fn ok(t: T) -> ExpandResult<T> {
254 ExpandResult(t, None)
255 }
256
257 pub fn only_err(err: ExpandError) -> ExpandResult<T>
258 where
259 T: Default,
260 {
261 ExpandResult(Default::default(), Some(err))
262 }
263
264 pub fn map<U>(self, f: impl FnOnce(T) -> U) -> ExpandResult<U> {
265 ExpandResult(f(self.0), self.1)
266 }
267
268 pub fn result(self) -> Result<T, ExpandError> {
269 self.1.map(Err).unwrap_or(Ok(self.0))
270 }
271}
272
273impl<T: Default> From<Result<T, ExpandError>> for ExpandResult<T> {
274 fn from(result: Result<T, ExpandError>) -> ExpandResult<T> {
275 result
276 .map_or_else(|e| ExpandResult(Default::default(), Some(e)), |it| ExpandResult(it, None))
277 }
278}
diff --git a/crates/mbe/src/mbe_expander.rs b/crates/mbe/src/mbe_expander.rs
new file mode 100644
index 000000000..1ad8b9f8a
--- /dev/null
+++ b/crates/mbe/src/mbe_expander.rs
@@ -0,0 +1,180 @@
1//! This module takes a (parsed) definition of `macro_rules` invocation, a
2//! `tt::TokenTree` representing an argument of macro invocation, and produces a
3//! `tt::TokenTree` for the result of the expansion.
4
5mod matcher;
6mod transcriber;
7
8use rustc_hash::FxHashMap;
9use syntax::SmolStr;
10
11use crate::{ExpandError, ExpandResult};
12
13pub(crate) fn expand(rules: &crate::MacroRules, input: &tt::Subtree) -> ExpandResult<tt::Subtree> {
14 expand_rules(&rules.rules, input)
15}
16
17fn expand_rules(rules: &[crate::Rule], input: &tt::Subtree) -> ExpandResult<tt::Subtree> {
18 let mut match_: Option<(matcher::Match, &crate::Rule)> = None;
19 for rule in rules {
20 let new_match = match matcher::match_(&rule.lhs, input) {
21 Ok(m) => m,
22 Err(_e) => {
23 // error in pattern parsing
24 continue;
25 }
26 };
27 if new_match.err.is_none() {
28 // If we find a rule that applies without errors, we're done.
29 // Unconditionally returning the transcription here makes the
30 // `test_repeat_bad_var` test fail.
31 let ExpandResult(res, transcribe_err) =
32 transcriber::transcribe(&rule.rhs, &new_match.bindings);
33 if transcribe_err.is_none() {
34 return ExpandResult::ok(res);
35 }
36 }
37 // Use the rule if we matched more tokens, or had fewer errors
38 if let Some((prev_match, _)) = &match_ {
39 if (new_match.unmatched_tts, new_match.err_count)
40 < (prev_match.unmatched_tts, prev_match.err_count)
41 {
42 match_ = Some((new_match, rule));
43 }
44 } else {
45 match_ = Some((new_match, rule));
46 }
47 }
48 if let Some((match_, rule)) = match_ {
49 // if we got here, there was no match without errors
50 let ExpandResult(result, transcribe_err) =
51 transcriber::transcribe(&rule.rhs, &match_.bindings);
52 ExpandResult(result, match_.err.or(transcribe_err))
53 } else {
54 ExpandResult(tt::Subtree::default(), Some(ExpandError::NoMatchingRule))
55 }
56}
57
58/// The actual algorithm for expansion is not too hard, but is pretty tricky.
59/// `Bindings` structure is the key to understanding what we are doing here.
60///
61/// On the high level, it stores mapping from meta variables to the bits of
62/// syntax it should be substituted with. For example, if `$e:expr` is matched
63/// with `1 + 1` by macro_rules, the `Binding` will store `$e -> 1 + 1`.
64///
65/// The tricky bit is dealing with repetitions (`$()*`). Consider this example:
66///
67/// ```not_rust
68/// macro_rules! foo {
69/// ($($ i:ident $($ e:expr),*);*) => {
70/// $(fn $ i() { $($ e);*; })*
71/// }
72/// }
73/// foo! { foo 1,2,3; bar 4,5,6 }
74/// ```
75///
76/// Here, the `$i` meta variable is matched first with `foo` and then with
77/// `bar`, and `$e` is matched in turn with `1`, `2`, `3`, `4`, `5`, `6`.
78///
79/// To represent such "multi-mappings", we use a recursive structures: we map
80/// variables not to values, but to *lists* of values or other lists (that is,
81/// to the trees).
82///
83/// For the above example, the bindings would store
84///
85/// ```not_rust
86/// i -> [foo, bar]
87/// e -> [[1, 2, 3], [4, 5, 6]]
88/// ```
89///
90/// We construct `Bindings` in the `match_lhs`. The interesting case is
91/// `TokenTree::Repeat`, where we use `push_nested` to create the desired
92/// nesting structure.
93///
94/// The other side of the puzzle is `expand_subtree`, where we use the bindings
95/// to substitute meta variables in the output template. When expanding, we
96/// maintain a `nesting` stack of indices which tells us which occurrence from
97/// the `Bindings` we should take. We push to the stack when we enter a
98/// repetition.
99///
100/// In other words, `Bindings` is a *multi* mapping from `SmolStr` to
101/// `tt::TokenTree`, where the index to select a particular `TokenTree` among
102/// many is not a plain `usize`, but an `&[usize]`.
103#[derive(Debug, Default)]
104struct Bindings {
105 inner: FxHashMap<SmolStr, Binding>,
106}
107
108#[derive(Debug)]
109enum Binding {
110 Fragment(Fragment),
111 Nested(Vec<Binding>),
112 Empty,
113}
114
115#[derive(Debug, Clone)]
116enum Fragment {
117 /// token fragments are just copy-pasted into the output
118 Tokens(tt::TokenTree),
119 /// Ast fragments are inserted with fake delimiters, so as to make things
120 /// like `$i * 2` where `$i = 1 + 1` work as expectd.
121 Ast(tt::TokenTree),
122}
123
124#[cfg(test)]
125mod tests {
126 use syntax::{ast, AstNode};
127
128 use super::*;
129 use crate::ast_to_token_tree;
130
131 #[test]
132 fn test_expand_rule() {
133 assert_err(
134 "($($i:ident);*) => ($i)",
135 "foo!{a}",
136 ExpandError::BindingError(String::from(
137 "expected simple binding, found nested binding `i`",
138 )),
139 );
140
141 // FIXME:
142 // Add an err test case for ($($i:ident)) => ($())
143 }
144
145 fn assert_err(macro_body: &str, invocation: &str, err: ExpandError) {
146 assert_eq!(expand_first(&create_rules(&format_macro(macro_body)), invocation).1, Some(err));
147 }
148
149 fn format_macro(macro_body: &str) -> String {
150 format!(
151 "
152 macro_rules! foo {{
153 {}
154 }}
155",
156 macro_body
157 )
158 }
159
160 fn create_rules(macro_definition: &str) -> crate::MacroRules {
161 let source_file = ast::SourceFile::parse(macro_definition).ok().unwrap();
162 let macro_definition =
163 source_file.syntax().descendants().find_map(ast::MacroCall::cast).unwrap();
164
165 let (definition_tt, _) =
166 ast_to_token_tree(&macro_definition.token_tree().unwrap()).unwrap();
167 crate::MacroRules::parse(&definition_tt).unwrap()
168 }
169
170 fn expand_first(rules: &crate::MacroRules, invocation: &str) -> ExpandResult<tt::Subtree> {
171 let source_file = ast::SourceFile::parse(invocation).ok().unwrap();
172 let macro_invocation =
173 source_file.syntax().descendants().find_map(ast::MacroCall::cast).unwrap();
174
175 let (invocation_tt, _) =
176 ast_to_token_tree(&macro_invocation.token_tree().unwrap()).unwrap();
177
178 expand_rules(&rules.rules, &invocation_tt)
179 }
180}
diff --git a/crates/mbe/src/mbe_expander/matcher.rs b/crates/mbe/src/mbe_expander/matcher.rs
new file mode 100644
index 000000000..b698b9832
--- /dev/null
+++ b/crates/mbe/src/mbe_expander/matcher.rs
@@ -0,0 +1,477 @@
1//! FIXME: write short doc here
2
3use crate::{
4 mbe_expander::{Binding, Bindings, Fragment},
5 parser::{parse_pattern, Op, RepeatKind, Separator},
6 subtree_source::SubtreeTokenSource,
7 tt_iter::TtIter,
8 ExpandError,
9};
10
11use super::ExpandResult;
12use parser::{FragmentKind::*, TreeSink};
13use syntax::{SmolStr, SyntaxKind};
14use tt::buffer::{Cursor, TokenBuffer};
15
16impl Bindings {
17 fn push_optional(&mut self, name: &SmolStr) {
18 // FIXME: Do we have a better way to represent an empty token ?
19 // Insert an empty subtree for empty token
20 let tt = tt::Subtree::default().into();
21 self.inner.insert(name.clone(), Binding::Fragment(Fragment::Tokens(tt)));
22 }
23
24 fn push_empty(&mut self, name: &SmolStr) {
25 self.inner.insert(name.clone(), Binding::Empty);
26 }
27
28 fn push_nested(&mut self, idx: usize, nested: Bindings) -> Result<(), ExpandError> {
29 for (key, value) in nested.inner {
30 if !self.inner.contains_key(&key) {
31 self.inner.insert(key.clone(), Binding::Nested(Vec::new()));
32 }
33 match self.inner.get_mut(&key) {
34 Some(Binding::Nested(it)) => {
35 // insert empty nested bindings before this one
36 while it.len() < idx {
37 it.push(Binding::Nested(vec![]));
38 }
39 it.push(value);
40 }
41 _ => {
42 return Err(ExpandError::BindingError(format!(
43 "could not find binding `{}`",
44 key
45 )));
46 }
47 }
48 }
49 Ok(())
50 }
51}
52
53macro_rules! err {
54 () => {
55 ExpandError::BindingError(format!(""))
56 };
57 ($($tt:tt)*) => {
58 ExpandError::BindingError(format!($($tt)*))
59 };
60}
61
62#[derive(Debug, Default)]
63pub(super) struct Match {
64 pub bindings: Bindings,
65 /// We currently just keep the first error and count the rest to compare matches.
66 pub err: Option<ExpandError>,
67 pub err_count: usize,
68 /// How many top-level token trees were left to match.
69 pub unmatched_tts: usize,
70}
71
72impl Match {
73 pub fn add_err(&mut self, err: ExpandError) {
74 let prev_err = self.err.take();
75 self.err = prev_err.or(Some(err));
76 self.err_count += 1;
77 }
78}
79
80// General note: These functions have two channels to return errors, a `Result`
81// return value and the `&mut Match`. The returned Result is for pattern parsing
82// errors; if a branch of the macro definition doesn't parse, it doesn't make
83// sense to try using it. Matching errors are added to the `Match`. It might
84// make sense to make pattern parsing a separate step?
85
86pub(super) fn match_(pattern: &tt::Subtree, src: &tt::Subtree) -> Result<Match, ExpandError> {
87 assert!(pattern.delimiter == None);
88
89 let mut res = Match::default();
90 let mut src = TtIter::new(src);
91
92 match_subtree(&mut res, pattern, &mut src)?;
93
94 if src.len() > 0 {
95 res.unmatched_tts += src.len();
96 res.add_err(err!("leftover tokens"));
97 }
98
99 Ok(res)
100}
101
102fn match_subtree(
103 res: &mut Match,
104 pattern: &tt::Subtree,
105 src: &mut TtIter,
106) -> Result<(), ExpandError> {
107 for op in parse_pattern(pattern) {
108 match op? {
109 Op::TokenTree(tt::TokenTree::Leaf(lhs)) => {
110 let rhs = match src.expect_leaf() {
111 Ok(l) => l,
112 Err(()) => {
113 res.add_err(err!("expected leaf: `{}`", lhs));
114 continue;
115 }
116 };
117 match (lhs, rhs) {
118 (
119 tt::Leaf::Punct(tt::Punct { char: lhs, .. }),
120 tt::Leaf::Punct(tt::Punct { char: rhs, .. }),
121 ) if lhs == rhs => (),
122 (
123 tt::Leaf::Ident(tt::Ident { text: lhs, .. }),
124 tt::Leaf::Ident(tt::Ident { text: rhs, .. }),
125 ) if lhs == rhs => (),
126 (
127 tt::Leaf::Literal(tt::Literal { text: lhs, .. }),
128 tt::Leaf::Literal(tt::Literal { text: rhs, .. }),
129 ) if lhs == rhs => (),
130 _ => {
131 res.add_err(ExpandError::UnexpectedToken);
132 }
133 }
134 }
135 Op::TokenTree(tt::TokenTree::Subtree(lhs)) => {
136 let rhs = match src.expect_subtree() {
137 Ok(s) => s,
138 Err(()) => {
139 res.add_err(err!("expected subtree"));
140 continue;
141 }
142 };
143 if lhs.delimiter_kind() != rhs.delimiter_kind() {
144 res.add_err(err!("mismatched delimiter"));
145 continue;
146 }
147 let mut src = TtIter::new(rhs);
148 match_subtree(res, lhs, &mut src)?;
149 if src.len() > 0 {
150 res.add_err(err!("leftover tokens"));
151 }
152 }
153 Op::Var { name, kind } => {
154 let kind = match kind {
155 Some(k) => k,
156 None => {
157 res.add_err(ExpandError::UnexpectedToken);
158 continue;
159 }
160 };
161 let ExpandResult(matched, match_err) = match_meta_var(kind.as_str(), src);
162 match matched {
163 Some(fragment) => {
164 res.bindings.inner.insert(name.clone(), Binding::Fragment(fragment));
165 }
166 None if match_err.is_none() => res.bindings.push_optional(name),
167 _ => {}
168 }
169 if let Some(err) = match_err {
170 res.add_err(err);
171 }
172 }
173 Op::Repeat { subtree, kind, separator } => {
174 match_repeat(res, subtree, kind, separator, src)?;
175 }
176 }
177 }
178 Ok(())
179}
180
181impl<'a> TtIter<'a> {
182 fn eat_separator(&mut self, separator: &Separator) -> bool {
183 let mut fork = self.clone();
184 let ok = match separator {
185 Separator::Ident(lhs) => match fork.expect_ident() {
186 Ok(rhs) => rhs.text == lhs.text,
187 _ => false,
188 },
189 Separator::Literal(lhs) => match fork.expect_literal() {
190 Ok(rhs) => match rhs {
191 tt::Leaf::Literal(rhs) => rhs.text == lhs.text,
192 tt::Leaf::Ident(rhs) => rhs.text == lhs.text,
193 tt::Leaf::Punct(_) => false,
194 },
195 _ => false,
196 },
197 Separator::Puncts(lhss) => lhss.iter().all(|lhs| match fork.expect_punct() {
198 Ok(rhs) => rhs.char == lhs.char,
199 _ => false,
200 }),
201 };
202 if ok {
203 *self = fork;
204 }
205 ok
206 }
207
208 pub(crate) fn expect_tt(&mut self) -> Result<tt::TokenTree, ()> {
209 match self.peek_n(0) {
210 Some(tt::TokenTree::Leaf(tt::Leaf::Punct(punct))) if punct.char == '\'' => {
211 return self.expect_lifetime();
212 }
213 _ => (),
214 }
215
216 let tt = self.next().ok_or_else(|| ())?.clone();
217 let punct = match tt {
218 tt::TokenTree::Leaf(tt::Leaf::Punct(punct)) if punct.spacing == tt::Spacing::Joint => {
219 punct
220 }
221 _ => return Ok(tt),
222 };
223
224 let (second, third) = match (self.peek_n(0), self.peek_n(1)) {
225 (
226 Some(tt::TokenTree::Leaf(tt::Leaf::Punct(p2))),
227 Some(tt::TokenTree::Leaf(tt::Leaf::Punct(p3))),
228 ) if p2.spacing == tt::Spacing::Joint => (p2.char, Some(p3.char)),
229 (Some(tt::TokenTree::Leaf(tt::Leaf::Punct(p2))), _) => (p2.char, None),
230 _ => return Ok(tt),
231 };
232
233 match (punct.char, second, third) {
234 ('.', '.', Some('.'))
235 | ('.', '.', Some('='))
236 | ('<', '<', Some('='))
237 | ('>', '>', Some('=')) => {
238 let tt2 = self.next().unwrap().clone();
239 let tt3 = self.next().unwrap().clone();
240 Ok(tt::Subtree { delimiter: None, token_trees: vec![tt, tt2, tt3] }.into())
241 }
242 ('-', '=', None)
243 | ('-', '>', None)
244 | (':', ':', None)
245 | ('!', '=', None)
246 | ('.', '.', None)
247 | ('*', '=', None)
248 | ('/', '=', None)
249 | ('&', '&', None)
250 | ('&', '=', None)
251 | ('%', '=', None)
252 | ('^', '=', None)
253 | ('+', '=', None)
254 | ('<', '<', None)
255 | ('<', '=', None)
256 | ('=', '=', None)
257 | ('=', '>', None)
258 | ('>', '=', None)
259 | ('>', '>', None)
260 | ('|', '=', None)
261 | ('|', '|', None) => {
262 let tt2 = self.next().unwrap().clone();
263 Ok(tt::Subtree { delimiter: None, token_trees: vec![tt, tt2] }.into())
264 }
265 _ => Ok(tt),
266 }
267 }
268
269 pub(crate) fn expect_lifetime(&mut self) -> Result<tt::TokenTree, ()> {
270 let punct = self.expect_punct()?;
271 if punct.char != '\'' {
272 return Err(());
273 }
274 let ident = self.expect_ident()?;
275
276 Ok(tt::Subtree {
277 delimiter: None,
278 token_trees: vec![
279 tt::Leaf::Punct(*punct).into(),
280 tt::Leaf::Ident(ident.clone()).into(),
281 ],
282 }
283 .into())
284 }
285
286 pub(crate) fn expect_fragment(
287 &mut self,
288 fragment_kind: parser::FragmentKind,
289 ) -> ExpandResult<Option<tt::TokenTree>> {
290 pub(crate) struct OffsetTokenSink<'a> {
291 pub(crate) cursor: Cursor<'a>,
292 pub(crate) error: bool,
293 }
294
295 impl<'a> TreeSink for OffsetTokenSink<'a> {
296 fn token(&mut self, kind: SyntaxKind, mut n_tokens: u8) {
297 if kind == SyntaxKind::LIFETIME {
298 n_tokens = 2;
299 }
300 for _ in 0..n_tokens {
301 self.cursor = self.cursor.bump_subtree();
302 }
303 }
304 fn start_node(&mut self, _kind: SyntaxKind) {}
305 fn finish_node(&mut self) {}
306 fn error(&mut self, _error: parser::ParseError) {
307 self.error = true;
308 }
309 }
310
311 let buffer = TokenBuffer::new(&self.inner.as_slice());
312 let mut src = SubtreeTokenSource::new(&buffer);
313 let mut sink = OffsetTokenSink { cursor: buffer.begin(), error: false };
314
315 parser::parse_fragment(&mut src, &mut sink, fragment_kind);
316
317 let mut err = None;
318 if !sink.cursor.is_root() || sink.error {
319 err = Some(err!("expected {:?}", fragment_kind));
320 }
321
322 let mut curr = buffer.begin();
323 let mut res = vec![];
324
325 if sink.cursor.is_root() {
326 while curr != sink.cursor {
327 if let Some(token) = curr.token_tree() {
328 res.push(token);
329 }
330 curr = curr.bump();
331 }
332 }
333 self.inner = self.inner.as_slice()[res.len()..].iter();
334 if res.len() == 0 && err.is_none() {
335 err = Some(err!("no tokens consumed"));
336 }
337 let res = match res.len() {
338 1 => Some(res[0].clone()),
339 0 => None,
340 _ => Some(tt::TokenTree::Subtree(tt::Subtree {
341 delimiter: None,
342 token_trees: res.into_iter().cloned().collect(),
343 })),
344 };
345 ExpandResult(res, err)
346 }
347
348 pub(crate) fn eat_vis(&mut self) -> Option<tt::TokenTree> {
349 let mut fork = self.clone();
350 match fork.expect_fragment(Visibility) {
351 ExpandResult(tt, None) => {
352 *self = fork;
353 tt
354 }
355 ExpandResult(_, Some(_)) => None,
356 }
357 }
358}
359
360pub(super) fn match_repeat(
361 res: &mut Match,
362 pattern: &tt::Subtree,
363 kind: RepeatKind,
364 separator: Option<Separator>,
365 src: &mut TtIter,
366) -> Result<(), ExpandError> {
367 // Dirty hack to make macro-expansion terminate.
368 // This should be replaced by a propper macro-by-example implementation
369 let mut limit = 65536;
370 let mut counter = 0;
371
372 for i in 0.. {
373 let mut fork = src.clone();
374
375 if let Some(separator) = &separator {
376 if i != 0 && !fork.eat_separator(separator) {
377 break;
378 }
379 }
380
381 let mut nested = Match::default();
382 match_subtree(&mut nested, pattern, &mut fork)?;
383 if nested.err.is_none() {
384 limit -= 1;
385 if limit == 0 {
386 log::warn!(
387 "match_lhs exceeded repeat pattern limit => {:#?}\n{:#?}\n{:#?}\n{:#?}",
388 pattern,
389 src,
390 kind,
391 separator
392 );
393 break;
394 }
395 *src = fork;
396
397 if let Err(err) = res.bindings.push_nested(counter, nested.bindings) {
398 res.add_err(err);
399 }
400 counter += 1;
401 if counter == 1 {
402 if let RepeatKind::ZeroOrOne = kind {
403 break;
404 }
405 }
406 } else {
407 break;
408 }
409 }
410
411 match (kind, counter) {
412 (RepeatKind::OneOrMore, 0) => {
413 res.add_err(ExpandError::UnexpectedToken);
414 }
415 (_, 0) => {
416 // Collect all empty variables in subtrees
417 let mut vars = Vec::new();
418 collect_vars(&mut vars, pattern)?;
419 for var in vars {
420 res.bindings.push_empty(&var)
421 }
422 }
423 _ => (),
424 }
425 Ok(())
426}
427
428fn match_meta_var(kind: &str, input: &mut TtIter) -> ExpandResult<Option<Fragment>> {
429 let fragment = match kind {
430 "path" => Path,
431 "expr" => Expr,
432 "ty" => Type,
433 "pat" => Pattern,
434 "stmt" => Statement,
435 "block" => Block,
436 "meta" => MetaItem,
437 "item" => Item,
438 _ => {
439 let tt_result = match kind {
440 "ident" => input
441 .expect_ident()
442 .map(|ident| Some(tt::Leaf::from(ident.clone()).into()))
443 .map_err(|()| err!("expected ident")),
444 "tt" => input.expect_tt().map(Some).map_err(|()| err!()),
445 "lifetime" => input
446 .expect_lifetime()
447 .map(|tt| Some(tt))
448 .map_err(|()| err!("expected lifetime")),
449 "literal" => input
450 .expect_literal()
451 .map(|literal| Some(tt::Leaf::from(literal.clone()).into()))
452 .map_err(|()| err!()),
453 // `vis` is optional
454 "vis" => match input.eat_vis() {
455 Some(vis) => Ok(Some(vis)),
456 None => Ok(None),
457 },
458 _ => Err(ExpandError::UnexpectedToken),
459 };
460 return tt_result.map(|it| it.map(Fragment::Tokens)).into();
461 }
462 };
463 let result = input.expect_fragment(fragment);
464 result.map(|tt| if kind == "expr" { tt.map(Fragment::Ast) } else { tt.map(Fragment::Tokens) })
465}
466
467fn collect_vars(buf: &mut Vec<SmolStr>, pattern: &tt::Subtree) -> Result<(), ExpandError> {
468 for op in parse_pattern(pattern) {
469 match op? {
470 Op::Var { name, .. } => buf.push(name.clone()),
471 Op::TokenTree(tt::TokenTree::Leaf(_)) => (),
472 Op::TokenTree(tt::TokenTree::Subtree(subtree)) => collect_vars(buf, subtree)?,
473 Op::Repeat { subtree, .. } => collect_vars(buf, subtree)?,
474 }
475 }
476 Ok(())
477}
diff --git a/crates/mbe/src/mbe_expander/transcriber.rs b/crates/mbe/src/mbe_expander/transcriber.rs
new file mode 100644
index 000000000..c9525c5bf
--- /dev/null
+++ b/crates/mbe/src/mbe_expander/transcriber.rs
@@ -0,0 +1,254 @@
1//! Transcriber takes a template, like `fn $ident() {}`, a set of bindings like
2//! `$ident => foo`, interpolates variables in the template, to get `fn foo() {}`
3
4use syntax::SmolStr;
5
6use super::ExpandResult;
7use crate::{
8 mbe_expander::{Binding, Bindings, Fragment},
9 parser::{parse_template, Op, RepeatKind, Separator},
10 ExpandError,
11};
12
13impl Bindings {
14 fn contains(&self, name: &str) -> bool {
15 self.inner.contains_key(name)
16 }
17
18 fn get(&self, name: &str, nesting: &mut [NestingState]) -> Result<&Fragment, ExpandError> {
19 let mut b = self.inner.get(name).ok_or_else(|| {
20 ExpandError::BindingError(format!("could not find binding `{}`", name))
21 })?;
22 for nesting_state in nesting.iter_mut() {
23 nesting_state.hit = true;
24 b = match b {
25 Binding::Fragment(_) => break,
26 Binding::Nested(bs) => bs.get(nesting_state.idx).ok_or_else(|| {
27 nesting_state.at_end = true;
28 ExpandError::BindingError(format!("could not find nested binding `{}`", name))
29 })?,
30 Binding::Empty => {
31 nesting_state.at_end = true;
32 return Err(ExpandError::BindingError(format!(
33 "could not find empty binding `{}`",
34 name
35 )));
36 }
37 };
38 }
39 match b {
40 Binding::Fragment(it) => Ok(it),
41 Binding::Nested(_) => Err(ExpandError::BindingError(format!(
42 "expected simple binding, found nested binding `{}`",
43 name
44 ))),
45 Binding::Empty => Err(ExpandError::BindingError(format!(
46 "expected simple binding, found empty binding `{}`",
47 name
48 ))),
49 }
50 }
51}
52
53pub(super) fn transcribe(template: &tt::Subtree, bindings: &Bindings) -> ExpandResult<tt::Subtree> {
54 assert!(template.delimiter == None);
55 let mut ctx = ExpandCtx { bindings: &bindings, nesting: Vec::new() };
56 let mut arena: Vec<tt::TokenTree> = Vec::new();
57 expand_subtree(&mut ctx, template, &mut arena)
58}
59
60#[derive(Debug)]
61struct NestingState {
62 idx: usize,
63 /// `hit` is currently necessary to tell `expand_repeat` if it should stop
64 /// because there is no variable in use by the current repetition
65 hit: bool,
66 /// `at_end` is currently necessary to tell `expand_repeat` if it should stop
67 /// because there is no more value avaible for the current repetition
68 at_end: bool,
69}
70
71#[derive(Debug)]
72struct ExpandCtx<'a> {
73 bindings: &'a Bindings,
74 nesting: Vec<NestingState>,
75}
76
77fn expand_subtree(
78 ctx: &mut ExpandCtx,
79 template: &tt::Subtree,
80 arena: &mut Vec<tt::TokenTree>,
81) -> ExpandResult<tt::Subtree> {
82 // remember how many elements are in the arena now - when returning, we want to drain exactly how many elements we added. This way, the recursive uses of the arena get their own "view" of the arena, but will reuse the allocation
83 let start_elements = arena.len();
84 let mut err = None;
85 for op in parse_template(template) {
86 let op = match op {
87 Ok(op) => op,
88 Err(e) => {
89 err = Some(e);
90 break;
91 }
92 };
93 match op {
94 Op::TokenTree(tt @ tt::TokenTree::Leaf(..)) => arena.push(tt.clone()),
95 Op::TokenTree(tt::TokenTree::Subtree(tt)) => {
96 let ExpandResult(tt, e) = expand_subtree(ctx, tt, arena);
97 err = err.or(e);
98 arena.push(tt.into());
99 }
100 Op::Var { name, kind: _ } => {
101 let ExpandResult(fragment, e) = expand_var(ctx, name);
102 err = err.or(e);
103 push_fragment(arena, fragment);
104 }
105 Op::Repeat { subtree, kind, separator } => {
106 let ExpandResult(fragment, e) = expand_repeat(ctx, subtree, kind, separator, arena);
107 err = err.or(e);
108 push_fragment(arena, fragment)
109 }
110 }
111 }
112 // drain the elements added in this instance of expand_subtree
113 let tts = arena.drain(start_elements..arena.len()).collect();
114 ExpandResult(tt::Subtree { delimiter: template.delimiter, token_trees: tts }, err)
115}
116
117fn expand_var(ctx: &mut ExpandCtx, v: &SmolStr) -> ExpandResult<Fragment> {
118 if v == "crate" {
119 // We simply produce identifier `$crate` here. And it will be resolved when lowering ast to Path.
120 let tt =
121 tt::Leaf::from(tt::Ident { text: "$crate".into(), id: tt::TokenId::unspecified() })
122 .into();
123 ExpandResult::ok(Fragment::Tokens(tt))
124 } else if !ctx.bindings.contains(v) {
125 // Note that it is possible to have a `$var` inside a macro which is not bound.
126 // For example:
127 // ```
128 // macro_rules! foo {
129 // ($a:ident, $b:ident, $c:tt) => {
130 // macro_rules! bar {
131 // ($bi:ident) => {
132 // fn $bi() -> u8 {$c}
133 // }
134 // }
135 // }
136 // ```
137 // We just treat it a normal tokens
138 let tt = tt::Subtree {
139 delimiter: None,
140 token_trees: vec![
141 tt::Leaf::from(tt::Punct {
142 char: '$',
143 spacing: tt::Spacing::Alone,
144 id: tt::TokenId::unspecified(),
145 })
146 .into(),
147 tt::Leaf::from(tt::Ident { text: v.clone(), id: tt::TokenId::unspecified() })
148 .into(),
149 ],
150 }
151 .into();
152 ExpandResult::ok(Fragment::Tokens(tt))
153 } else {
154 ctx.bindings.get(&v, &mut ctx.nesting).map_or_else(
155 |e| ExpandResult(Fragment::Tokens(tt::TokenTree::empty()), Some(e)),
156 |b| ExpandResult::ok(b.clone()),
157 )
158 }
159}
160
161fn expand_repeat(
162 ctx: &mut ExpandCtx,
163 template: &tt::Subtree,
164 kind: RepeatKind,
165 separator: Option<Separator>,
166 arena: &mut Vec<tt::TokenTree>,
167) -> ExpandResult<Fragment> {
168 let mut buf: Vec<tt::TokenTree> = Vec::new();
169 ctx.nesting.push(NestingState { idx: 0, at_end: false, hit: false });
170 // Dirty hack to make macro-expansion terminate.
171 // This should be replaced by a proper macro-by-example implementation
172 let limit = 65536;
173 let mut has_seps = 0;
174 let mut counter = 0;
175
176 loop {
177 let ExpandResult(mut t, e) = expand_subtree(ctx, template, arena);
178 let nesting_state = ctx.nesting.last_mut().unwrap();
179 if nesting_state.at_end || !nesting_state.hit {
180 break;
181 }
182 nesting_state.idx += 1;
183 nesting_state.hit = false;
184
185 counter += 1;
186 if counter == limit {
187 log::warn!(
188 "expand_tt excced in repeat pattern exceed limit => {:#?}\n{:#?}",
189 template,
190 ctx
191 );
192 break;
193 }
194
195 if e.is_some() {
196 continue;
197 }
198
199 t.delimiter = None;
200 push_subtree(&mut buf, t);
201
202 if let Some(ref sep) = separator {
203 match sep {
204 Separator::Ident(ident) => {
205 has_seps = 1;
206 buf.push(tt::Leaf::from(ident.clone()).into());
207 }
208 Separator::Literal(lit) => {
209 has_seps = 1;
210 buf.push(tt::Leaf::from(lit.clone()).into());
211 }
212
213 Separator::Puncts(puncts) => {
214 has_seps = puncts.len();
215 for punct in puncts {
216 buf.push(tt::Leaf::from(*punct).into());
217 }
218 }
219 }
220 }
221
222 if RepeatKind::ZeroOrOne == kind {
223 break;
224 }
225 }
226
227 ctx.nesting.pop().unwrap();
228 for _ in 0..has_seps {
229 buf.pop();
230 }
231
232 // Check if it is a single token subtree without any delimiter
233 // e.g {Delimiter:None> ['>'] /Delimiter:None>}
234 let tt = tt::Subtree { delimiter: None, token_trees: buf }.into();
235
236 if RepeatKind::OneOrMore == kind && counter == 0 {
237 return ExpandResult(Fragment::Tokens(tt), Some(ExpandError::UnexpectedToken));
238 }
239 ExpandResult::ok(Fragment::Tokens(tt))
240}
241
242fn push_fragment(buf: &mut Vec<tt::TokenTree>, fragment: Fragment) {
243 match fragment {
244 Fragment::Tokens(tt::TokenTree::Subtree(tt)) => push_subtree(buf, tt),
245 Fragment::Tokens(tt) | Fragment::Ast(tt) => buf.push(tt),
246 }
247}
248
249fn push_subtree(buf: &mut Vec<tt::TokenTree>, tt: tt::Subtree) {
250 match tt.delimiter {
251 None => buf.extend(tt.token_trees),
252 _ => buf.push(tt.into()),
253 }
254}
diff --git a/crates/mbe/src/parser.rs b/crates/mbe/src/parser.rs
new file mode 100644
index 000000000..6b46a1673
--- /dev/null
+++ b/crates/mbe/src/parser.rs
@@ -0,0 +1,184 @@
1//! Parser recognizes special macro syntax, `$var` and `$(repeat)*`, in token
2//! trees.
3
4use smallvec::SmallVec;
5use syntax::SmolStr;
6
7use crate::{tt_iter::TtIter, ExpandError};
8
9#[derive(Debug)]
10pub(crate) enum Op<'a> {
11 Var { name: &'a SmolStr, kind: Option<&'a SmolStr> },
12 Repeat { subtree: &'a tt::Subtree, kind: RepeatKind, separator: Option<Separator> },
13 TokenTree(&'a tt::TokenTree),
14}
15
16#[derive(Clone, Debug, PartialEq, Eq)]
17pub(crate) enum RepeatKind {
18 ZeroOrMore,
19 OneOrMore,
20 ZeroOrOne,
21}
22
23#[derive(Clone, Debug, Eq)]
24pub(crate) enum Separator {
25 Literal(tt::Literal),
26 Ident(tt::Ident),
27 Puncts(SmallVec<[tt::Punct; 3]>),
28}
29
30// Note that when we compare a Separator, we just care about its textual value.
31impl PartialEq for Separator {
32 fn eq(&self, other: &Separator) -> bool {
33 use Separator::*;
34
35 match (self, other) {
36 (Ident(ref a), Ident(ref b)) => a.text == b.text,
37 (Literal(ref a), Literal(ref b)) => a.text == b.text,
38 (Puncts(ref a), Puncts(ref b)) if a.len() == b.len() => {
39 let a_iter = a.iter().map(|a| a.char);
40 let b_iter = b.iter().map(|b| b.char);
41 a_iter.eq(b_iter)
42 }
43 _ => false,
44 }
45 }
46}
47
48pub(crate) fn parse_template(
49 template: &tt::Subtree,
50) -> impl Iterator<Item = Result<Op<'_>, ExpandError>> {
51 parse_inner(template, Mode::Template)
52}
53
54pub(crate) fn parse_pattern(
55 pattern: &tt::Subtree,
56) -> impl Iterator<Item = Result<Op<'_>, ExpandError>> {
57 parse_inner(pattern, Mode::Pattern)
58}
59
60#[derive(Clone, Copy)]
61enum Mode {
62 Pattern,
63 Template,
64}
65
66fn parse_inner(src: &tt::Subtree, mode: Mode) -> impl Iterator<Item = Result<Op<'_>, ExpandError>> {
67 let mut src = TtIter::new(src);
68 std::iter::from_fn(move || {
69 let first = src.next()?;
70 Some(next_op(first, &mut src, mode))
71 })
72}
73
74macro_rules! err {
75 ($($tt:tt)*) => {
76 ExpandError::UnexpectedToken
77 };
78}
79
80macro_rules! bail {
81 ($($tt:tt)*) => {
82 return Err(err!($($tt)*))
83 };
84}
85
86fn next_op<'a>(
87 first: &'a tt::TokenTree,
88 src: &mut TtIter<'a>,
89 mode: Mode,
90) -> Result<Op<'a>, ExpandError> {
91 let res = match first {
92 tt::TokenTree::Leaf(tt::Leaf::Punct(tt::Punct { char: '$', .. })) => {
93 // Note that the '$' itself is a valid token inside macro_rules.
94 let second = match src.next() {
95 None => return Ok(Op::TokenTree(first)),
96 Some(it) => it,
97 };
98 match second {
99 tt::TokenTree::Subtree(subtree) => {
100 let (separator, kind) = parse_repeat(src)?;
101 Op::Repeat { subtree, separator, kind }
102 }
103 tt::TokenTree::Leaf(leaf) => match leaf {
104 tt::Leaf::Punct(..) => return Err(ExpandError::UnexpectedToken),
105 tt::Leaf::Ident(ident) => {
106 let name = &ident.text;
107 let kind = eat_fragment_kind(src, mode)?;
108 Op::Var { name, kind }
109 }
110 tt::Leaf::Literal(lit) => {
111 if is_boolean_literal(lit) {
112 let name = &lit.text;
113 let kind = eat_fragment_kind(src, mode)?;
114 Op::Var { name, kind }
115 } else {
116 bail!("bad var 2");
117 }
118 }
119 },
120 }
121 }
122 tt => Op::TokenTree(tt),
123 };
124 Ok(res)
125}
126
127fn eat_fragment_kind<'a>(
128 src: &mut TtIter<'a>,
129 mode: Mode,
130) -> Result<Option<&'a SmolStr>, ExpandError> {
131 if let Mode::Pattern = mode {
132 src.expect_char(':').map_err(|()| err!("bad fragment specifier 1"))?;
133 let ident = src.expect_ident().map_err(|()| err!("bad fragment specifier 1"))?;
134 return Ok(Some(&ident.text));
135 };
136 Ok(None)
137}
138
139fn is_boolean_literal(lit: &tt::Literal) -> bool {
140 matches!(lit.text.as_str(), "true" | "false")
141}
142
143fn parse_repeat(src: &mut TtIter) -> Result<(Option<Separator>, RepeatKind), ExpandError> {
144 let mut separator = Separator::Puncts(SmallVec::new());
145 for tt in src {
146 let tt = match tt {
147 tt::TokenTree::Leaf(leaf) => leaf,
148 tt::TokenTree::Subtree(_) => return Err(ExpandError::InvalidRepeat),
149 };
150 let has_sep = match &separator {
151 Separator::Puncts(puncts) => !puncts.is_empty(),
152 _ => true,
153 };
154 match tt {
155 tt::Leaf::Ident(_) | tt::Leaf::Literal(_) if has_sep => {
156 return Err(ExpandError::InvalidRepeat)
157 }
158 tt::Leaf::Ident(ident) => separator = Separator::Ident(ident.clone()),
159 tt::Leaf::Literal(lit) => separator = Separator::Literal(lit.clone()),
160 tt::Leaf::Punct(punct) => {
161 let repeat_kind = match punct.char {
162 '*' => RepeatKind::ZeroOrMore,
163 '+' => RepeatKind::OneOrMore,
164 '?' => RepeatKind::ZeroOrOne,
165 _ => {
166 match &mut separator {
167 Separator::Puncts(puncts) => {
168 if puncts.len() == 3 {
169 return Err(ExpandError::InvalidRepeat);
170 }
171 puncts.push(punct.clone())
172 }
173 _ => return Err(ExpandError::InvalidRepeat),
174 }
175 continue;
176 }
177 };
178 let separator = if has_sep { Some(separator) } else { None };
179 return Ok((separator, repeat_kind));
180 }
181 }
182 }
183 Err(ExpandError::InvalidRepeat)
184}
diff --git a/crates/mbe/src/subtree_source.rs b/crates/mbe/src/subtree_source.rs
new file mode 100644
index 000000000..41461b315
--- /dev/null
+++ b/crates/mbe/src/subtree_source.rs
@@ -0,0 +1,197 @@
1//! FIXME: write short doc here
2
3use parser::{Token, TokenSource};
4use std::cell::{Cell, Ref, RefCell};
5use syntax::{lex_single_syntax_kind, SmolStr, SyntaxKind, SyntaxKind::*, T};
6use tt::buffer::{Cursor, TokenBuffer};
7
8#[derive(Debug, Clone, Eq, PartialEq)]
9struct TtToken {
10 pub kind: SyntaxKind,
11 pub is_joint_to_next: bool,
12 pub text: SmolStr,
13}
14
15pub(crate) struct SubtreeTokenSource<'a> {
16 cached_cursor: Cell<Cursor<'a>>,
17 cached: RefCell<Vec<Option<TtToken>>>,
18 curr: (Token, usize),
19}
20
21impl<'a> SubtreeTokenSource<'a> {
22 // Helper function used in test
23 #[cfg(test)]
24 pub fn text(&self) -> SmolStr {
25 match *self.get(self.curr.1) {
26 Some(ref tt) => tt.text.clone(),
27 _ => SmolStr::new(""),
28 }
29 }
30}
31
32impl<'a> SubtreeTokenSource<'a> {
33 pub fn new(buffer: &'a TokenBuffer) -> SubtreeTokenSource<'a> {
34 let cursor = buffer.begin();
35
36 let mut res = SubtreeTokenSource {
37 curr: (Token { kind: EOF, is_jointed_to_next: false }, 0),
38 cached_cursor: Cell::new(cursor),
39 cached: RefCell::new(Vec::with_capacity(10)),
40 };
41 res.curr = (res.mk_token(0), 0);
42 res
43 }
44
45 fn mk_token(&self, pos: usize) -> Token {
46 match *self.get(pos) {
47 Some(ref tt) => Token { kind: tt.kind, is_jointed_to_next: tt.is_joint_to_next },
48 None => Token { kind: EOF, is_jointed_to_next: false },
49 }
50 }
51
52 fn get(&self, pos: usize) -> Ref<Option<TtToken>> {
53 fn is_lifetime(c: Cursor) -> Option<(Cursor, SmolStr)> {
54 let tkn = c.token_tree();
55
56 if let Some(tt::TokenTree::Leaf(tt::Leaf::Punct(punct))) = tkn {
57 if punct.char == '\'' {
58 let next = c.bump();
59 if let Some(tt::TokenTree::Leaf(tt::Leaf::Ident(ident))) = next.token_tree() {
60 let res_cursor = next.bump();
61 let text = SmolStr::new("'".to_string() + &ident.to_string());
62
63 return Some((res_cursor, text));
64 } else {
65 panic!("Next token must be ident : {:#?}", next.token_tree());
66 }
67 }
68 }
69
70 None
71 }
72
73 if pos < self.cached.borrow().len() {
74 return Ref::map(self.cached.borrow(), |c| &c[pos]);
75 }
76
77 {
78 let mut cached = self.cached.borrow_mut();
79 while pos >= cached.len() {
80 let cursor = self.cached_cursor.get();
81 if cursor.eof() {
82 cached.push(None);
83 continue;
84 }
85
86 if let Some((curr, text)) = is_lifetime(cursor) {
87 cached.push(Some(TtToken { kind: LIFETIME, is_joint_to_next: false, text }));
88 self.cached_cursor.set(curr);
89 continue;
90 }
91
92 match cursor.token_tree() {
93 Some(tt::TokenTree::Leaf(leaf)) => {
94 cached.push(Some(convert_leaf(&leaf)));
95 self.cached_cursor.set(cursor.bump());
96 }
97 Some(tt::TokenTree::Subtree(subtree)) => {
98 self.cached_cursor.set(cursor.subtree().unwrap());
99 cached.push(Some(convert_delim(subtree.delimiter_kind(), false)));
100 }
101 None => {
102 if let Some(subtree) = cursor.end() {
103 cached.push(Some(convert_delim(subtree.delimiter_kind(), true)));
104 self.cached_cursor.set(cursor.bump());
105 }
106 }
107 }
108 }
109 }
110
111 Ref::map(self.cached.borrow(), |c| &c[pos])
112 }
113}
114
115impl<'a> TokenSource for SubtreeTokenSource<'a> {
116 fn current(&self) -> Token {
117 self.curr.0
118 }
119
120 /// Lookahead n token
121 fn lookahead_nth(&self, n: usize) -> Token {
122 self.mk_token(self.curr.1 + n)
123 }
124
125 /// bump cursor to next token
126 fn bump(&mut self) {
127 if self.current().kind == EOF {
128 return;
129 }
130
131 self.curr = (self.mk_token(self.curr.1 + 1), self.curr.1 + 1);
132 }
133
134 /// Is the current token a specified keyword?
135 fn is_keyword(&self, kw: &str) -> bool {
136 match *self.get(self.curr.1) {
137 Some(ref t) => t.text == *kw,
138 _ => false,
139 }
140 }
141}
142
143fn convert_delim(d: Option<tt::DelimiterKind>, closing: bool) -> TtToken {
144 let (kinds, texts) = match d {
145 Some(tt::DelimiterKind::Parenthesis) => ([T!['('], T![')']], "()"),
146 Some(tt::DelimiterKind::Brace) => ([T!['{'], T!['}']], "{}"),
147 Some(tt::DelimiterKind::Bracket) => ([T!['['], T![']']], "[]"),
148 None => ([L_DOLLAR, R_DOLLAR], ""),
149 };
150
151 let idx = closing as usize;
152 let kind = kinds[idx];
153 let text = if !texts.is_empty() { &texts[idx..texts.len() - (1 - idx)] } else { "" };
154 TtToken { kind, is_joint_to_next: false, text: SmolStr::new(text) }
155}
156
157fn convert_literal(l: &tt::Literal) -> TtToken {
158 let kind = lex_single_syntax_kind(&l.text)
159 .map(|(kind, _error)| kind)
160 .filter(|kind| kind.is_literal())
161 .unwrap_or_else(|| panic!("Fail to convert given literal {:#?}", &l));
162
163 TtToken { kind, is_joint_to_next: false, text: l.text.clone() }
164}
165
166fn convert_ident(ident: &tt::Ident) -> TtToken {
167 let kind = match ident.text.as_ref() {
168 "true" => T![true],
169 "false" => T![false],
170 i if i.starts_with('\'') => LIFETIME,
171 _ => SyntaxKind::from_keyword(ident.text.as_str()).unwrap_or(IDENT),
172 };
173
174 TtToken { kind, is_joint_to_next: false, text: ident.text.clone() }
175}
176
177fn convert_punct(p: tt::Punct) -> TtToken {
178 let kind = match SyntaxKind::from_char(p.char) {
179 None => panic!("{:#?} is not a valid punct", p),
180 Some(kind) => kind,
181 };
182
183 let text = {
184 let mut buf = [0u8; 4];
185 let s: &str = p.char.encode_utf8(&mut buf);
186 SmolStr::new(s)
187 };
188 TtToken { kind, is_joint_to_next: p.spacing == tt::Spacing::Joint, text }
189}
190
191fn convert_leaf(leaf: &tt::Leaf) -> TtToken {
192 match leaf {
193 tt::Leaf::Literal(l) => convert_literal(l),
194 tt::Leaf::Ident(ident) => convert_ident(ident),
195 tt::Leaf::Punct(punct) => convert_punct(*punct),
196 }
197}
diff --git a/crates/mbe/src/syntax_bridge.rs b/crates/mbe/src/syntax_bridge.rs
new file mode 100644
index 000000000..a8ad917fb
--- /dev/null
+++ b/crates/mbe/src/syntax_bridge.rs
@@ -0,0 +1,832 @@
1//! FIXME: write short doc here
2
3use parser::{FragmentKind, ParseError, TreeSink};
4use rustc_hash::FxHashMap;
5use syntax::{
6 ast::{self, make::tokens::doc_comment},
7 tokenize, AstToken, Parse, SmolStr, SyntaxKind,
8 SyntaxKind::*,
9 SyntaxNode, SyntaxToken, SyntaxTreeBuilder, TextRange, TextSize, Token as RawToken, T,
10};
11use tt::buffer::{Cursor, TokenBuffer};
12
13use crate::subtree_source::SubtreeTokenSource;
14use crate::ExpandError;
15
16#[derive(Debug, PartialEq, Eq, Clone, Copy)]
17pub enum TokenTextRange {
18 Token(TextRange),
19 Delimiter(TextRange, TextRange),
20}
21
22impl TokenTextRange {
23 pub fn by_kind(self, kind: SyntaxKind) -> Option<TextRange> {
24 match self {
25 TokenTextRange::Token(it) => Some(it),
26 TokenTextRange::Delimiter(open, close) => match kind {
27 T!['{'] | T!['('] | T!['['] => Some(open),
28 T!['}'] | T![')'] | T![']'] => Some(close),
29 _ => None,
30 },
31 }
32 }
33}
34
35/// Maps `tt::TokenId` to the relative range of the original token.
36#[derive(Debug, PartialEq, Eq, Clone, Default)]
37pub struct TokenMap {
38 /// Maps `tt::TokenId` to the *relative* source range.
39 entries: Vec<(tt::TokenId, TokenTextRange)>,
40}
41
42/// Convert the syntax tree (what user has written) to a `TokenTree` (what macro
43/// will consume).
44pub fn ast_to_token_tree(ast: &impl ast::AstNode) -> Option<(tt::Subtree, TokenMap)> {
45 syntax_node_to_token_tree(ast.syntax())
46}
47
48/// Convert the syntax node to a `TokenTree` (what macro
49/// will consume).
50pub fn syntax_node_to_token_tree(node: &SyntaxNode) -> Option<(tt::Subtree, TokenMap)> {
51 let global_offset = node.text_range().start();
52 let mut c = Convertor::new(node, global_offset);
53 let subtree = c.go()?;
54 Some((subtree, c.id_alloc.map))
55}
56
57// The following items are what `rustc` macro can be parsed into :
58// link: https://github.com/rust-lang/rust/blob/9ebf47851a357faa4cd97f4b1dc7835f6376e639/src/libsyntax/ext/expand.rs#L141
59// * Expr(P<ast::Expr>) -> token_tree_to_expr
60// * Pat(P<ast::Pat>) -> token_tree_to_pat
61// * Ty(P<ast::Ty>) -> token_tree_to_ty
62// * Stmts(SmallVec<[ast::Stmt; 1]>) -> token_tree_to_stmts
63// * Items(SmallVec<[P<ast::Item>; 1]>) -> token_tree_to_items
64//
65// * TraitItems(SmallVec<[ast::TraitItem; 1]>)
66// * AssocItems(SmallVec<[ast::AssocItem; 1]>)
67// * ForeignItems(SmallVec<[ast::ForeignItem; 1]>
68
69pub fn token_tree_to_syntax_node(
70 tt: &tt::Subtree,
71 fragment_kind: FragmentKind,
72) -> Result<(Parse<SyntaxNode>, TokenMap), ExpandError> {
73 let tmp;
74 let tokens = match tt {
75 tt::Subtree { delimiter: None, token_trees } => token_trees.as_slice(),
76 _ => {
77 tmp = [tt.clone().into()];
78 &tmp[..]
79 }
80 };
81 let buffer = TokenBuffer::new(&tokens);
82 let mut token_source = SubtreeTokenSource::new(&buffer);
83 let mut tree_sink = TtTreeSink::new(buffer.begin());
84 parser::parse_fragment(&mut token_source, &mut tree_sink, fragment_kind);
85 if tree_sink.roots.len() != 1 {
86 return Err(ExpandError::ConversionError);
87 }
88 //FIXME: would be cool to report errors
89 let (parse, range_map) = tree_sink.finish();
90 Ok((parse, range_map))
91}
92
93/// Convert a string to a `TokenTree`
94pub fn parse_to_token_tree(text: &str) -> Option<(tt::Subtree, TokenMap)> {
95 let (tokens, errors) = tokenize(text);
96 if !errors.is_empty() {
97 return None;
98 }
99
100 let mut conv = RawConvertor {
101 text,
102 offset: TextSize::default(),
103 inner: tokens.iter(),
104 id_alloc: TokenIdAlloc {
105 map: Default::default(),
106 global_offset: TextSize::default(),
107 next_id: 0,
108 },
109 };
110
111 let subtree = conv.go()?;
112 Some((subtree, conv.id_alloc.map))
113}
114
115impl TokenMap {
116 pub fn token_by_range(&self, relative_range: TextRange) -> Option<tt::TokenId> {
117 let &(token_id, _) = self.entries.iter().find(|(_, range)| match range {
118 TokenTextRange::Token(it) => *it == relative_range,
119 TokenTextRange::Delimiter(open, close) => {
120 *open == relative_range || *close == relative_range
121 }
122 })?;
123 Some(token_id)
124 }
125
126 pub fn range_by_token(&self, token_id: tt::TokenId) -> Option<TokenTextRange> {
127 let &(_, range) = self.entries.iter().find(|(tid, _)| *tid == token_id)?;
128 Some(range)
129 }
130
131 fn insert(&mut self, token_id: tt::TokenId, relative_range: TextRange) {
132 self.entries.push((token_id, TokenTextRange::Token(relative_range)));
133 }
134
135 fn insert_delim(
136 &mut self,
137 token_id: tt::TokenId,
138 open_relative_range: TextRange,
139 close_relative_range: TextRange,
140 ) -> usize {
141 let res = self.entries.len();
142 self.entries
143 .push((token_id, TokenTextRange::Delimiter(open_relative_range, close_relative_range)));
144 res
145 }
146
147 fn update_close_delim(&mut self, idx: usize, close_relative_range: TextRange) {
148 let (_, token_text_range) = &mut self.entries[idx];
149 if let TokenTextRange::Delimiter(dim, _) = token_text_range {
150 *token_text_range = TokenTextRange::Delimiter(*dim, close_relative_range);
151 }
152 }
153
154 fn remove_delim(&mut self, idx: usize) {
155 // FIXME: This could be accidently quadratic
156 self.entries.remove(idx);
157 }
158}
159
160/// Returns the textual content of a doc comment block as a quoted string
161/// That is, strips leading `///` (or `/**`, etc)
162/// and strips the ending `*/`
163/// And then quote the string, which is needed to convert to `tt::Literal`
164fn doc_comment_text(comment: &ast::Comment) -> SmolStr {
165 let prefix_len = comment.prefix().len();
166 let mut text = &comment.text()[prefix_len..];
167
168 // Remove ending "*/"
169 if comment.kind().shape == ast::CommentShape::Block {
170 text = &text[0..text.len() - 2];
171 }
172
173 // Quote the string
174 // Note that `tt::Literal` expect an escaped string
175 let text = format!("{:?}", text.escape_default().to_string());
176 text.into()
177}
178
179fn convert_doc_comment(token: &syntax::SyntaxToken) -> Option<Vec<tt::TokenTree>> {
180 let comment = ast::Comment::cast(token.clone())?;
181 let doc = comment.kind().doc?;
182
183 // Make `doc="\" Comments\""
184 let mut meta_tkns = Vec::new();
185 meta_tkns.push(mk_ident("doc"));
186 meta_tkns.push(mk_punct('='));
187 meta_tkns.push(mk_doc_literal(&comment));
188
189 // Make `#![]`
190 let mut token_trees = Vec::new();
191 token_trees.push(mk_punct('#'));
192 if let ast::CommentPlacement::Inner = doc {
193 token_trees.push(mk_punct('!'));
194 }
195 token_trees.push(tt::TokenTree::from(tt::Subtree {
196 delimiter: Some(tt::Delimiter {
197 kind: tt::DelimiterKind::Bracket,
198 id: tt::TokenId::unspecified(),
199 }),
200 token_trees: meta_tkns,
201 }));
202
203 return Some(token_trees);
204
205 // Helper functions
206 fn mk_ident(s: &str) -> tt::TokenTree {
207 tt::TokenTree::from(tt::Leaf::from(tt::Ident {
208 text: s.into(),
209 id: tt::TokenId::unspecified(),
210 }))
211 }
212
213 fn mk_punct(c: char) -> tt::TokenTree {
214 tt::TokenTree::from(tt::Leaf::from(tt::Punct {
215 char: c,
216 spacing: tt::Spacing::Alone,
217 id: tt::TokenId::unspecified(),
218 }))
219 }
220
221 fn mk_doc_literal(comment: &ast::Comment) -> tt::TokenTree {
222 let lit = tt::Literal { text: doc_comment_text(comment), id: tt::TokenId::unspecified() };
223
224 tt::TokenTree::from(tt::Leaf::from(lit))
225 }
226}
227
228struct TokenIdAlloc {
229 map: TokenMap,
230 global_offset: TextSize,
231 next_id: u32,
232}
233
234impl TokenIdAlloc {
235 fn alloc(&mut self, absolute_range: TextRange) -> tt::TokenId {
236 let relative_range = absolute_range - self.global_offset;
237 let token_id = tt::TokenId(self.next_id);
238 self.next_id += 1;
239 self.map.insert(token_id, relative_range);
240 token_id
241 }
242
243 fn open_delim(&mut self, open_abs_range: TextRange) -> (tt::TokenId, usize) {
244 let token_id = tt::TokenId(self.next_id);
245 self.next_id += 1;
246 let idx = self.map.insert_delim(
247 token_id,
248 open_abs_range - self.global_offset,
249 open_abs_range - self.global_offset,
250 );
251 (token_id, idx)
252 }
253
254 fn close_delim(&mut self, idx: usize, close_abs_range: Option<TextRange>) {
255 match close_abs_range {
256 None => {
257 self.map.remove_delim(idx);
258 }
259 Some(close) => {
260 self.map.update_close_delim(idx, close - self.global_offset);
261 }
262 }
263 }
264}
265
266/// A Raw Token (straightly from lexer) convertor
267struct RawConvertor<'a> {
268 text: &'a str,
269 offset: TextSize,
270 id_alloc: TokenIdAlloc,
271 inner: std::slice::Iter<'a, RawToken>,
272}
273
274trait SrcToken: std::fmt::Debug {
275 fn kind(&self) -> SyntaxKind;
276
277 fn to_char(&self) -> Option<char>;
278
279 fn to_text(&self) -> SmolStr;
280}
281
282trait TokenConvertor {
283 type Token: SrcToken;
284
285 fn go(&mut self) -> Option<tt::Subtree> {
286 let mut subtree = tt::Subtree::default();
287 subtree.delimiter = None;
288 while self.peek().is_some() {
289 self.collect_leaf(&mut subtree.token_trees);
290 }
291 if subtree.token_trees.is_empty() {
292 return None;
293 }
294 if subtree.token_trees.len() == 1 {
295 if let tt::TokenTree::Subtree(first) = &subtree.token_trees[0] {
296 return Some(first.clone());
297 }
298 }
299 Some(subtree)
300 }
301
302 fn collect_leaf(&mut self, result: &mut Vec<tt::TokenTree>) {
303 let (token, range) = match self.bump() {
304 None => return,
305 Some(it) => it,
306 };
307
308 let k: SyntaxKind = token.kind();
309 if k == COMMENT {
310 if let Some(tokens) = self.convert_doc_comment(&token) {
311 result.extend(tokens);
312 }
313 return;
314 }
315
316 result.push(if k.is_punct() {
317 assert_eq!(range.len(), TextSize::of('.'));
318 let delim = match k {
319 T!['('] => Some((tt::DelimiterKind::Parenthesis, T![')'])),
320 T!['{'] => Some((tt::DelimiterKind::Brace, T!['}'])),
321 T!['['] => Some((tt::DelimiterKind::Bracket, T![']'])),
322 _ => None,
323 };
324
325 if let Some((kind, closed)) = delim {
326 let mut subtree = tt::Subtree::default();
327 let (id, idx) = self.id_alloc().open_delim(range);
328 subtree.delimiter = Some(tt::Delimiter { kind, id });
329
330 while self.peek().map(|it| it.kind() != closed).unwrap_or(false) {
331 self.collect_leaf(&mut subtree.token_trees);
332 }
333 let last_range = match self.bump() {
334 None => {
335 // For error resilience, we insert an char punct for the opening delim here
336 self.id_alloc().close_delim(idx, None);
337 let leaf: tt::Leaf = tt::Punct {
338 id: self.id_alloc().alloc(range),
339 char: token.to_char().unwrap(),
340 spacing: tt::Spacing::Alone,
341 }
342 .into();
343 result.push(leaf.into());
344 result.extend(subtree.token_trees);
345 return;
346 }
347 Some(it) => it.1,
348 };
349 self.id_alloc().close_delim(idx, Some(last_range));
350 subtree.into()
351 } else {
352 let spacing = match self.peek() {
353 Some(next)
354 if next.kind().is_trivia()
355 || next.kind() == T!['[']
356 || next.kind() == T!['{']
357 || next.kind() == T!['('] =>
358 {
359 tt::Spacing::Alone
360 }
361 Some(next) if next.kind().is_punct() => tt::Spacing::Joint,
362 _ => tt::Spacing::Alone,
363 };
364 let char = match token.to_char() {
365 Some(c) => c,
366 None => {
367 panic!("Token from lexer must be single char: token = {:#?}", token);
368 }
369 };
370 tt::Leaf::from(tt::Punct { char, spacing, id: self.id_alloc().alloc(range) }).into()
371 }
372 } else {
373 macro_rules! make_leaf {
374 ($i:ident) => {
375 tt::$i { id: self.id_alloc().alloc(range), text: token.to_text() }.into()
376 };
377 }
378 let leaf: tt::Leaf = match k {
379 T![true] | T![false] => make_leaf!(Ident),
380 IDENT => make_leaf!(Ident),
381 k if k.is_keyword() => make_leaf!(Ident),
382 k if k.is_literal() => make_leaf!(Literal),
383 LIFETIME => {
384 let char_unit = TextSize::of('\'');
385 let r = TextRange::at(range.start(), char_unit);
386 let apostrophe = tt::Leaf::from(tt::Punct {
387 char: '\'',
388 spacing: tt::Spacing::Joint,
389 id: self.id_alloc().alloc(r),
390 });
391 result.push(apostrophe.into());
392
393 let r = TextRange::at(range.start() + char_unit, range.len() - char_unit);
394 let ident = tt::Leaf::from(tt::Ident {
395 text: SmolStr::new(&token.to_text()[1..]),
396 id: self.id_alloc().alloc(r),
397 });
398 result.push(ident.into());
399 return;
400 }
401 _ => return,
402 };
403
404 leaf.into()
405 });
406 }
407
408 fn convert_doc_comment(&self, token: &Self::Token) -> Option<Vec<tt::TokenTree>>;
409
410 fn bump(&mut self) -> Option<(Self::Token, TextRange)>;
411
412 fn peek(&self) -> Option<Self::Token>;
413
414 fn id_alloc(&mut self) -> &mut TokenIdAlloc;
415}
416
417impl<'a> SrcToken for (RawToken, &'a str) {
418 fn kind(&self) -> SyntaxKind {
419 self.0.kind
420 }
421
422 fn to_char(&self) -> Option<char> {
423 self.1.chars().next()
424 }
425
426 fn to_text(&self) -> SmolStr {
427 self.1.into()
428 }
429}
430
431impl RawConvertor<'_> {}
432
433impl<'a> TokenConvertor for RawConvertor<'a> {
434 type Token = (RawToken, &'a str);
435
436 fn convert_doc_comment(&self, token: &Self::Token) -> Option<Vec<tt::TokenTree>> {
437 convert_doc_comment(&doc_comment(token.1))
438 }
439
440 fn bump(&mut self) -> Option<(Self::Token, TextRange)> {
441 let token = self.inner.next()?;
442 let range = TextRange::at(self.offset, token.len);
443 self.offset += token.len;
444
445 Some(((*token, &self.text[range]), range))
446 }
447
448 fn peek(&self) -> Option<Self::Token> {
449 let token = self.inner.as_slice().get(0).cloned();
450
451 token.map(|it| {
452 let range = TextRange::at(self.offset, it.len);
453 (it, &self.text[range])
454 })
455 }
456
457 fn id_alloc(&mut self) -> &mut TokenIdAlloc {
458 &mut self.id_alloc
459 }
460}
461
462struct Convertor {
463 id_alloc: TokenIdAlloc,
464 current: Option<SyntaxToken>,
465 range: TextRange,
466 punct_offset: Option<(SyntaxToken, TextSize)>,
467}
468
469impl Convertor {
470 fn new(node: &SyntaxNode, global_offset: TextSize) -> Convertor {
471 Convertor {
472 id_alloc: { TokenIdAlloc { map: TokenMap::default(), global_offset, next_id: 0 } },
473 current: node.first_token(),
474 range: node.text_range(),
475 punct_offset: None,
476 }
477 }
478}
479
480#[derive(Debug)]
481enum SynToken {
482 Ordiniary(SyntaxToken),
483 Punch(SyntaxToken, TextSize),
484}
485
486impl SynToken {
487 fn token(&self) -> &SyntaxToken {
488 match self {
489 SynToken::Ordiniary(it) => it,
490 SynToken::Punch(it, _) => it,
491 }
492 }
493}
494
495impl SrcToken for SynToken {
496 fn kind(&self) -> SyntaxKind {
497 self.token().kind()
498 }
499 fn to_char(&self) -> Option<char> {
500 match self {
501 SynToken::Ordiniary(_) => None,
502 SynToken::Punch(it, i) => it.text().chars().nth((*i).into()),
503 }
504 }
505 fn to_text(&self) -> SmolStr {
506 self.token().text().clone()
507 }
508}
509
510impl TokenConvertor for Convertor {
511 type Token = SynToken;
512 fn convert_doc_comment(&self, token: &Self::Token) -> Option<Vec<tt::TokenTree>> {
513 convert_doc_comment(token.token())
514 }
515
516 fn bump(&mut self) -> Option<(Self::Token, TextRange)> {
517 if let Some((punct, offset)) = self.punct_offset.clone() {
518 if usize::from(offset) + 1 < punct.text().len() {
519 let offset = offset + TextSize::of('.');
520 let range = punct.text_range();
521 self.punct_offset = Some((punct.clone(), offset));
522 let range = TextRange::at(range.start() + offset, TextSize::of('.'));
523 return Some((SynToken::Punch(punct, offset), range));
524 }
525 }
526
527 let curr = self.current.clone()?;
528 if !&self.range.contains_range(curr.text_range()) {
529 return None;
530 }
531 self.current = curr.next_token();
532
533 let token = if curr.kind().is_punct() {
534 let range = curr.text_range();
535 let range = TextRange::at(range.start(), TextSize::of('.'));
536 self.punct_offset = Some((curr.clone(), 0.into()));
537 (SynToken::Punch(curr, 0.into()), range)
538 } else {
539 self.punct_offset = None;
540 let range = curr.text_range();
541 (SynToken::Ordiniary(curr), range)
542 };
543
544 Some(token)
545 }
546
547 fn peek(&self) -> Option<Self::Token> {
548 if let Some((punct, mut offset)) = self.punct_offset.clone() {
549 offset = offset + TextSize::of('.');
550 if usize::from(offset) < punct.text().len() {
551 return Some(SynToken::Punch(punct, offset));
552 }
553 }
554
555 let curr = self.current.clone()?;
556 if !self.range.contains_range(curr.text_range()) {
557 return None;
558 }
559
560 let token = if curr.kind().is_punct() {
561 SynToken::Punch(curr, 0.into())
562 } else {
563 SynToken::Ordiniary(curr)
564 };
565 Some(token)
566 }
567
568 fn id_alloc(&mut self) -> &mut TokenIdAlloc {
569 &mut self.id_alloc
570 }
571}
572
573struct TtTreeSink<'a> {
574 buf: String,
575 cursor: Cursor<'a>,
576 open_delims: FxHashMap<tt::TokenId, TextSize>,
577 text_pos: TextSize,
578 inner: SyntaxTreeBuilder,
579 token_map: TokenMap,
580
581 // Number of roots
582 // Use for detect ill-form tree which is not single root
583 roots: smallvec::SmallVec<[usize; 1]>,
584}
585
586impl<'a> TtTreeSink<'a> {
587 fn new(cursor: Cursor<'a>) -> Self {
588 TtTreeSink {
589 buf: String::new(),
590 cursor,
591 open_delims: FxHashMap::default(),
592 text_pos: 0.into(),
593 inner: SyntaxTreeBuilder::default(),
594 roots: smallvec::SmallVec::new(),
595 token_map: TokenMap::default(),
596 }
597 }
598
599 fn finish(self) -> (Parse<SyntaxNode>, TokenMap) {
600 (self.inner.finish(), self.token_map)
601 }
602}
603
604fn delim_to_str(d: Option<tt::DelimiterKind>, closing: bool) -> SmolStr {
605 let texts = match d {
606 Some(tt::DelimiterKind::Parenthesis) => "()",
607 Some(tt::DelimiterKind::Brace) => "{}",
608 Some(tt::DelimiterKind::Bracket) => "[]",
609 None => return "".into(),
610 };
611
612 let idx = closing as usize;
613 let text = &texts[idx..texts.len() - (1 - idx)];
614 text.into()
615}
616
617impl<'a> TreeSink for TtTreeSink<'a> {
618 fn token(&mut self, kind: SyntaxKind, mut n_tokens: u8) {
619 if kind == L_DOLLAR || kind == R_DOLLAR {
620 self.cursor = self.cursor.bump_subtree();
621 return;
622 }
623 if kind == LIFETIME {
624 n_tokens = 2;
625 }
626
627 let mut last = self.cursor;
628 for _ in 0..n_tokens {
629 if self.cursor.eof() {
630 break;
631 }
632 last = self.cursor;
633 let text: SmolStr = match self.cursor.token_tree() {
634 Some(tt::TokenTree::Leaf(leaf)) => {
635 // Mark the range if needed
636 let (text, id) = match leaf {
637 tt::Leaf::Ident(ident) => (ident.text.clone(), ident.id),
638 tt::Leaf::Punct(punct) => {
639 (SmolStr::new_inline_from_ascii(1, &[punct.char as u8]), punct.id)
640 }
641 tt::Leaf::Literal(lit) => (lit.text.clone(), lit.id),
642 };
643 let range = TextRange::at(self.text_pos, TextSize::of(text.as_str()));
644 self.token_map.insert(id, range);
645 self.cursor = self.cursor.bump();
646 text
647 }
648 Some(tt::TokenTree::Subtree(subtree)) => {
649 self.cursor = self.cursor.subtree().unwrap();
650 if let Some(id) = subtree.delimiter.map(|it| it.id) {
651 self.open_delims.insert(id, self.text_pos);
652 }
653 delim_to_str(subtree.delimiter_kind(), false)
654 }
655 None => {
656 if let Some(parent) = self.cursor.end() {
657 self.cursor = self.cursor.bump();
658 if let Some(id) = parent.delimiter.map(|it| it.id) {
659 if let Some(open_delim) = self.open_delims.get(&id) {
660 let open_range = TextRange::at(*open_delim, TextSize::of('('));
661 let close_range = TextRange::at(self.text_pos, TextSize::of('('));
662 self.token_map.insert_delim(id, open_range, close_range);
663 }
664 }
665 delim_to_str(parent.delimiter_kind(), true)
666 } else {
667 continue;
668 }
669 }
670 };
671 self.buf += &text;
672 self.text_pos += TextSize::of(text.as_str());
673 }
674
675 let text = SmolStr::new(self.buf.as_str());
676 self.buf.clear();
677 self.inner.token(kind, text);
678
679 // Add whitespace between adjoint puncts
680 let next = last.bump();
681 if let (
682 Some(tt::TokenTree::Leaf(tt::Leaf::Punct(curr))),
683 Some(tt::TokenTree::Leaf(tt::Leaf::Punct(_))),
684 ) = (last.token_tree(), next.token_tree())
685 {
686 // Note: We always assume the semi-colon would be the last token in
687 // other parts of RA such that we don't add whitespace here.
688 if curr.spacing == tt::Spacing::Alone && curr.char != ';' {
689 self.inner.token(WHITESPACE, " ".into());
690 self.text_pos += TextSize::of(' ');
691 }
692 }
693 }
694
695 fn start_node(&mut self, kind: SyntaxKind) {
696 self.inner.start_node(kind);
697
698 match self.roots.last_mut() {
699 None | Some(0) => self.roots.push(1),
700 Some(ref mut n) => **n += 1,
701 };
702 }
703
704 fn finish_node(&mut self) {
705 self.inner.finish_node();
706 *self.roots.last_mut().unwrap() -= 1;
707 }
708
709 fn error(&mut self, error: ParseError) {
710 self.inner.error(error, self.text_pos)
711 }
712}
713
714#[cfg(test)]
715mod tests {
716 use super::*;
717 use crate::tests::parse_macro;
718 use parser::TokenSource;
719 use syntax::{
720 algo::{insert_children, InsertPosition},
721 ast::AstNode,
722 };
723
724 #[test]
725 fn convert_tt_token_source() {
726 let expansion = parse_macro(
727 r#"
728 macro_rules! literals {
729 ($i:ident) => {
730 {
731 let a = 'c';
732 let c = 1000;
733 let f = 12E+99_f64;
734 let s = "rust1";
735 }
736 }
737 }
738 "#,
739 )
740 .expand_tt("literals!(foo);");
741 let tts = &[expansion.into()];
742 let buffer = tt::buffer::TokenBuffer::new(tts);
743 let mut tt_src = SubtreeTokenSource::new(&buffer);
744 let mut tokens = vec![];
745 while tt_src.current().kind != EOF {
746 tokens.push((tt_src.current().kind, tt_src.text()));
747 tt_src.bump();
748 }
749
750 // [${]
751 // [let] [a] [=] ['c'] [;]
752 assert_eq!(tokens[2 + 3].1, "'c'");
753 assert_eq!(tokens[2 + 3].0, CHAR);
754 // [let] [c] [=] [1000] [;]
755 assert_eq!(tokens[2 + 5 + 3].1, "1000");
756 assert_eq!(tokens[2 + 5 + 3].0, INT_NUMBER);
757 // [let] [f] [=] [12E+99_f64] [;]
758 assert_eq!(tokens[2 + 10 + 3].1, "12E+99_f64");
759 assert_eq!(tokens[2 + 10 + 3].0, FLOAT_NUMBER);
760
761 // [let] [s] [=] ["rust1"] [;]
762 assert_eq!(tokens[2 + 15 + 3].1, "\"rust1\"");
763 assert_eq!(tokens[2 + 15 + 3].0, STRING);
764 }
765
766 #[test]
767 fn stmts_token_trees_to_expr_is_err() {
768 let expansion = parse_macro(
769 r#"
770 macro_rules! stmts {
771 () => {
772 let a = 0;
773 let b = 0;
774 let c = 0;
775 let d = 0;
776 }
777 }
778 "#,
779 )
780 .expand_tt("stmts!();");
781 assert!(token_tree_to_syntax_node(&expansion, FragmentKind::Expr).is_err());
782 }
783
784 #[test]
785 fn test_token_tree_last_child_is_white_space() {
786 let source_file = ast::SourceFile::parse("f!({} );").ok().unwrap();
787 let macro_call = source_file.syntax().descendants().find_map(ast::MacroCall::cast).unwrap();
788 let token_tree = macro_call.token_tree().unwrap();
789
790 // Token Tree now is :
791 // TokenTree
792 // - T!['(']
793 // - TokenTree
794 // - T!['{']
795 // - T!['}']
796 // - WHITE_SPACE
797 // - T![')']
798
799 let rbrace =
800 token_tree.syntax().descendants_with_tokens().find(|it| it.kind() == T!['}']).unwrap();
801 let space = token_tree
802 .syntax()
803 .descendants_with_tokens()
804 .find(|it| it.kind() == SyntaxKind::WHITESPACE)
805 .unwrap();
806
807 // reorder th white space, such that the white is inside the inner token-tree.
808 let token_tree = insert_children(
809 &rbrace.parent().unwrap(),
810 InsertPosition::Last,
811 std::iter::once(space),
812 );
813
814 // Token Tree now is :
815 // TokenTree
816 // - T!['{']
817 // - T!['}']
818 // - WHITE_SPACE
819 let token_tree = ast::TokenTree::cast(token_tree).unwrap();
820 let tt = ast_to_token_tree(&token_tree).unwrap().0;
821
822 assert_eq!(tt.delimiter_kind(), Some(tt::DelimiterKind::Brace));
823 }
824
825 #[test]
826 fn test_token_tree_multi_char_punct() {
827 let source_file = ast::SourceFile::parse("struct Foo { a: x::Y }").ok().unwrap();
828 let struct_def = source_file.syntax().descendants().find_map(ast::Struct::cast).unwrap();
829 let tt = ast_to_token_tree(&struct_def).unwrap().0;
830 token_tree_to_syntax_node(&tt, FragmentKind::Item).unwrap();
831 }
832}
diff --git a/crates/mbe/src/tests.rs b/crates/mbe/src/tests.rs
new file mode 100644
index 000000000..0796ceee1
--- /dev/null
+++ b/crates/mbe/src/tests.rs
@@ -0,0 +1,1898 @@
1use std::fmt::Write;
2
3use ::parser::FragmentKind;
4use syntax::{ast, AstNode, NodeOrToken, SyntaxKind::IDENT, SyntaxNode, WalkEvent, T};
5use test_utils::assert_eq_text;
6
7use super::*;
8
9mod rule_parsing {
10 use syntax::{ast, AstNode};
11
12 use crate::ast_to_token_tree;
13
14 use super::*;
15
16 #[test]
17 fn test_valid_arms() {
18 fn check(macro_body: &str) {
19 let m = parse_macro_arm(macro_body);
20 m.unwrap();
21 }
22
23 check("($i:ident) => ()");
24 check("($($i:ident)*) => ($_)");
25 check("($($true:ident)*) => ($true)");
26 check("($($false:ident)*) => ($false)");
27 check("($) => ($)");
28 }
29
30 #[test]
31 fn test_invalid_arms() {
32 fn check(macro_body: &str, err: &str) {
33 let m = parse_macro_arm(macro_body);
34 assert_eq!(m, Err(ParseError::Expected(String::from(err))));
35 }
36
37 check("invalid", "expected subtree");
38
39 check("$i:ident => ()", "expected subtree");
40 check("($i:ident) ()", "expected `=`");
41 check("($($i:ident)_) => ()", "invalid repeat");
42
43 check("($i) => ($i)", "invalid macro definition");
44 check("($i:) => ($i)", "invalid macro definition");
45 }
46
47 fn parse_macro_arm(arm_definition: &str) -> Result<crate::MacroRules, ParseError> {
48 let macro_definition = format!(" macro_rules! m {{ {} }} ", arm_definition);
49 let source_file = ast::SourceFile::parse(&macro_definition).ok().unwrap();
50 let macro_definition =
51 source_file.syntax().descendants().find_map(ast::MacroCall::cast).unwrap();
52
53 let (definition_tt, _) =
54 ast_to_token_tree(&macro_definition.token_tree().unwrap()).unwrap();
55 crate::MacroRules::parse(&definition_tt)
56 }
57}
58
59// Good first issue (although a slightly challenging one):
60//
61// * Pick a random test from here
62// https://github.com/intellij-rust/intellij-rust/blob/c4e9feee4ad46e7953b1948c112533360b6087bb/src/test/kotlin/org/rust/lang/core/macros/RsMacroExpansionTest.kt
63// * Port the test to rust and add it to this module
64// * Make it pass :-)
65
66#[test]
67fn test_token_id_shift() {
68 let expansion = parse_macro(
69 r#"
70macro_rules! foobar {
71 ($e:ident) => { foo bar $e }
72}
73"#,
74 )
75 .expand_tt("foobar!(baz);");
76
77 fn get_id(t: &tt::TokenTree) -> Option<u32> {
78 if let tt::TokenTree::Leaf(tt::Leaf::Ident(ident)) = t {
79 return Some(ident.id.0);
80 }
81 None
82 }
83
84 assert_eq!(expansion.token_trees.len(), 3);
85 // {($e:ident) => { foo bar $e }}
86 // 012345 67 8 9 T 12
87 assert_eq!(get_id(&expansion.token_trees[0]), Some(9));
88 assert_eq!(get_id(&expansion.token_trees[1]), Some(10));
89
90 // The input args of macro call include parentheses:
91 // (baz)
92 // So baz should be 12+1+1
93 assert_eq!(get_id(&expansion.token_trees[2]), Some(14));
94}
95
96#[test]
97fn test_token_map() {
98 let expanded = parse_macro(
99 r#"
100macro_rules! foobar {
101 ($e:ident) => { fn $e() {} }
102}
103"#,
104 )
105 .expand_tt("foobar!(baz);");
106
107 let (node, token_map) = token_tree_to_syntax_node(&expanded, FragmentKind::Items).unwrap();
108 let content = node.syntax_node().to_string();
109
110 let get_text = |id, kind| -> String {
111 content[token_map.range_by_token(id).unwrap().by_kind(kind).unwrap()].to_string()
112 };
113
114 assert_eq!(expanded.token_trees.len(), 4);
115 // {($e:ident) => { fn $e() {} }}
116 // 012345 67 8 9 T12 3
117
118 assert_eq!(get_text(tt::TokenId(9), IDENT), "fn");
119 assert_eq!(get_text(tt::TokenId(12), T!['(']), "(");
120 assert_eq!(get_text(tt::TokenId(13), T!['{']), "{");
121}
122
123#[test]
124fn test_convert_tt() {
125 parse_macro(r#"
126macro_rules! impl_froms {
127 ($e:ident: $($v:ident),*) => {
128 $(
129 impl From<$v> for $e {
130 fn from(it: $v) -> $e {
131 $e::$v(it)
132 }
133 }
134 )*
135 }
136}
137"#)
138 .assert_expand_tt(
139 "impl_froms!(TokenTree: Leaf, Subtree);",
140 "impl From <Leaf > for TokenTree {fn from (it : Leaf) -> TokenTree {TokenTree ::Leaf (it)}} \
141 impl From <Subtree > for TokenTree {fn from (it : Subtree) -> TokenTree {TokenTree ::Subtree (it)}}"
142 );
143}
144
145#[test]
146fn test_convert_tt2() {
147 parse_macro(
148 r#"
149macro_rules! impl_froms {
150 ($e:ident: $($v:ident),*) => {
151 $(
152 impl From<$v> for $e {
153 fn from(it: $v) -> $e {
154 $e::$v(it)
155 }
156 }
157 )*
158 }
159}
160"#,
161 )
162 .assert_expand(
163 "impl_froms!(TokenTree: Leaf, Subtree);",
164 r#"
165SUBTREE $
166 IDENT impl 20
167 IDENT From 21
168 PUNCH < [joint] 22
169 IDENT Leaf 53
170 PUNCH > [alone] 25
171 IDENT for 26
172 IDENT TokenTree 51
173 SUBTREE {} 29
174 IDENT fn 30
175 IDENT from 31
176 SUBTREE () 32
177 IDENT it 33
178 PUNCH : [alone] 34
179 IDENT Leaf 53
180 PUNCH - [joint] 37
181 PUNCH > [alone] 38
182 IDENT TokenTree 51
183 SUBTREE {} 41
184 IDENT TokenTree 51
185 PUNCH : [joint] 44
186 PUNCH : [joint] 45
187 IDENT Leaf 53
188 SUBTREE () 48
189 IDENT it 49
190 IDENT impl 20
191 IDENT From 21
192 PUNCH < [joint] 22
193 IDENT Subtree 55
194 PUNCH > [alone] 25
195 IDENT for 26
196 IDENT TokenTree 51
197 SUBTREE {} 29
198 IDENT fn 30
199 IDENT from 31
200 SUBTREE () 32
201 IDENT it 33
202 PUNCH : [alone] 34
203 IDENT Subtree 55
204 PUNCH - [joint] 37
205 PUNCH > [alone] 38
206 IDENT TokenTree 51
207 SUBTREE {} 41
208 IDENT TokenTree 51
209 PUNCH : [joint] 44
210 PUNCH : [joint] 45
211 IDENT Subtree 55
212 SUBTREE () 48
213 IDENT it 49
214"#,
215 );
216}
217
218#[test]
219fn test_lifetime_split() {
220 parse_macro(
221 r#"
222macro_rules! foo {
223 ($($t:tt)*) => { $($t)*}
224}
225"#,
226 )
227 .assert_expand(
228 r#"foo!(static bar: &'static str = "hello";);"#,
229 r#"
230SUBTREE $
231 IDENT static 17
232 IDENT bar 18
233 PUNCH : [alone] 19
234 PUNCH & [alone] 20
235 PUNCH ' [joint] 21
236 IDENT static 22
237 IDENT str 23
238 PUNCH = [alone] 24
239 LITERAL "hello" 25
240 PUNCH ; [joint] 26
241"#,
242 );
243}
244
245#[test]
246fn test_expr_order() {
247 let expanded = parse_macro(
248 r#"
249 macro_rules! foo {
250 ($ i:expr) => {
251 fn bar() { $ i * 2; }
252 }
253 }
254"#,
255 )
256 .expand_items("foo! { 1 + 1}");
257
258 let dump = format!("{:#?}", expanded);
259 assert_eq_text!(
260 dump.trim(),
261 r#"[email protected]
262 [email protected]
263 [email protected] "fn"
264 [email protected]
265 [email protected] "bar"
266 [email protected]
267 [email protected] "("
268 [email protected] ")"
269 [email protected]
270 [email protected] "{"
271 [email protected]
272 [email protected]
273 [email protected]
274 [email protected]
275 [email protected] "1"
276 [email protected] "+"
277 [email protected]
278 [email protected] "1"
279 [email protected] "*"
280 [email protected]
281 [email protected] "2"
282 [email protected] ";"
283 [email protected] "}""#,
284 );
285}
286
287#[test]
288fn test_fail_match_pattern_by_first_token() {
289 parse_macro(
290 r#"
291 macro_rules! foo {
292 ($ i:ident) => (
293 mod $ i {}
294 );
295 (= $ i:ident) => (
296 fn $ i() {}
297 );
298 (+ $ i:ident) => (
299 struct $ i;
300 )
301 }
302"#,
303 )
304 .assert_expand_items("foo! { foo }", "mod foo {}")
305 .assert_expand_items("foo! { = bar }", "fn bar () {}")
306 .assert_expand_items("foo! { + Baz }", "struct Baz ;");
307}
308
309#[test]
310fn test_fail_match_pattern_by_last_token() {
311 parse_macro(
312 r#"
313 macro_rules! foo {
314 ($ i:ident) => (
315 mod $ i {}
316 );
317 ($ i:ident =) => (
318 fn $ i() {}
319 );
320 ($ i:ident +) => (
321 struct $ i;
322 )
323 }
324"#,
325 )
326 .assert_expand_items("foo! { foo }", "mod foo {}")
327 .assert_expand_items("foo! { bar = }", "fn bar () {}")
328 .assert_expand_items("foo! { Baz + }", "struct Baz ;");
329}
330
331#[test]
332fn test_fail_match_pattern_by_word_token() {
333 parse_macro(
334 r#"
335 macro_rules! foo {
336 ($ i:ident) => (
337 mod $ i {}
338 );
339 (spam $ i:ident) => (
340 fn $ i() {}
341 );
342 (eggs $ i:ident) => (
343 struct $ i;
344 )
345 }
346"#,
347 )
348 .assert_expand_items("foo! { foo }", "mod foo {}")
349 .assert_expand_items("foo! { spam bar }", "fn bar () {}")
350 .assert_expand_items("foo! { eggs Baz }", "struct Baz ;");
351}
352
353#[test]
354fn test_match_group_pattern_by_separator_token() {
355 parse_macro(
356 r#"
357 macro_rules! foo {
358 ($ ($ i:ident),*) => ($ (
359 mod $ i {}
360 )*);
361 ($ ($ i:ident)#*) => ($ (
362 fn $ i() {}
363 )*);
364 ($ i:ident ,# $ j:ident) => (
365 struct $ i;
366 struct $ j;
367 )
368 }
369"#,
370 )
371 .assert_expand_items("foo! { foo, bar }", "mod foo {} mod bar {}")
372 .assert_expand_items("foo! { foo# bar }", "fn foo () {} fn bar () {}")
373 .assert_expand_items("foo! { Foo,# Bar }", "struct Foo ; struct Bar ;");
374}
375
376#[test]
377fn test_match_group_pattern_with_multiple_defs() {
378 parse_macro(
379 r#"
380 macro_rules! foo {
381 ($ ($ i:ident),*) => ( struct Bar { $ (
382 fn $ i {}
383 )*} );
384 }
385"#,
386 )
387 .assert_expand_items("foo! { foo, bar }", "struct Bar {fn foo {} fn bar {}}");
388}
389
390#[test]
391fn test_match_group_pattern_with_multiple_statement() {
392 parse_macro(
393 r#"
394 macro_rules! foo {
395 ($ ($ i:ident),*) => ( fn baz { $ (
396 $ i ();
397 )*} );
398 }
399"#,
400 )
401 .assert_expand_items("foo! { foo, bar }", "fn baz {foo () ; bar () ;}");
402}
403
404#[test]
405fn test_match_group_pattern_with_multiple_statement_without_semi() {
406 parse_macro(
407 r#"
408 macro_rules! foo {
409 ($ ($ i:ident),*) => ( fn baz { $ (
410 $i()
411 );*} );
412 }
413"#,
414 )
415 .assert_expand_items("foo! { foo, bar }", "fn baz {foo () ;bar ()}");
416}
417
418#[test]
419fn test_match_group_empty_fixed_token() {
420 parse_macro(
421 r#"
422 macro_rules! foo {
423 ($ ($ i:ident)* #abc) => ( fn baz { $ (
424 $ i ();
425 )*} );
426 }
427"#,
428 )
429 .assert_expand_items("foo! {#abc}", "fn baz {}");
430}
431
432#[test]
433fn test_match_group_in_subtree() {
434 parse_macro(
435 r#"
436 macro_rules! foo {
437 (fn $name:ident {$($i:ident)*} ) => ( fn $name() { $ (
438 $ i ();
439 )*} );
440 }"#,
441 )
442 .assert_expand_items("foo! {fn baz {a b} }", "fn baz () {a () ; b () ;}");
443}
444
445#[test]
446fn test_match_group_with_multichar_sep() {
447 parse_macro(
448 r#"
449 macro_rules! foo {
450 (fn $name:ident {$($i:literal)*} ) => ( fn $name() -> bool { $($i)&&*} );
451 }"#,
452 )
453 .assert_expand_items("foo! (fn baz {true true} );", "fn baz () -> bool {true &&true}");
454}
455
456#[test]
457fn test_match_group_zero_match() {
458 parse_macro(
459 r#"
460 macro_rules! foo {
461 ( $($i:ident)* ) => ();
462 }"#,
463 )
464 .assert_expand_items("foo! ();", "");
465}
466
467#[test]
468fn test_match_group_in_group() {
469 parse_macro(
470 r#"
471 macro_rules! foo {
472 { $( ( $($i:ident)* ) )* } => ( $( ( $($i)* ) )* );
473 }"#,
474 )
475 .assert_expand_items("foo! ( (a b) );", "(a b)");
476}
477
478#[test]
479fn test_expand_to_item_list() {
480 let tree = parse_macro(
481 "
482 macro_rules! structs {
483 ($($i:ident),*) => {
484 $(struct $i { field: u32 } )*
485 }
486 }
487 ",
488 )
489 .expand_items("structs!(Foo, Bar);");
490 assert_eq!(
491 format!("{:#?}", tree).trim(),
492 r#"
493[email protected]
494 [email protected]
495 [email protected] "struct"
496 [email protected]
497 [email protected] "Foo"
498 [email protected]
499 [email protected] "{"
500 [email protected]
501 [email protected]
502 [email protected] "field"
503 [email protected] ":"
504 [email protected]
505 [email protected]
506 [email protected]
507 [email protected]
508 [email protected] "u32"
509 [email protected] "}"
510 [email protected]
511 [email protected] "struct"
512 [email protected]
513 [email protected] "Bar"
514 [email protected]
515 [email protected] "{"
516 [email protected]
517 [email protected]
518 [email protected] "field"
519 [email protected] ":"
520 [email protected]
521 [email protected]
522 [email protected]
523 [email protected]
524 [email protected] "u32"
525 [email protected] "}""#
526 .trim()
527 );
528}
529
530fn to_subtree(tt: &tt::TokenTree) -> &tt::Subtree {
531 if let tt::TokenTree::Subtree(subtree) = tt {
532 return &subtree;
533 }
534 unreachable!("It is not a subtree");
535}
536fn to_literal(tt: &tt::TokenTree) -> &tt::Literal {
537 if let tt::TokenTree::Leaf(tt::Leaf::Literal(lit)) = tt {
538 return lit;
539 }
540 unreachable!("It is not a literal");
541}
542
543fn to_punct(tt: &tt::TokenTree) -> &tt::Punct {
544 if let tt::TokenTree::Leaf(tt::Leaf::Punct(lit)) = tt {
545 return lit;
546 }
547 unreachable!("It is not a Punct");
548}
549
550#[test]
551fn test_expand_literals_to_token_tree() {
552 let expansion = parse_macro(
553 r#"
554 macro_rules! literals {
555 ($i:ident) => {
556 {
557 let a = 'c';
558 let c = 1000;
559 let f = 12E+99_f64;
560 let s = "rust1";
561 }
562 }
563 }
564 "#,
565 )
566 .expand_tt("literals!(foo);");
567 let stm_tokens = &to_subtree(&expansion.token_trees[0]).token_trees;
568
569 // [let] [a] [=] ['c'] [;]
570 assert_eq!(to_literal(&stm_tokens[3]).text, "'c'");
571 // [let] [c] [=] [1000] [;]
572 assert_eq!(to_literal(&stm_tokens[5 + 3]).text, "1000");
573 // [let] [f] [=] [12E+99_f64] [;]
574 assert_eq!(to_literal(&stm_tokens[10 + 3]).text, "12E+99_f64");
575 // [let] [s] [=] ["rust1"] [;]
576 assert_eq!(to_literal(&stm_tokens[15 + 3]).text, "\"rust1\"");
577}
578
579#[test]
580fn test_attr_to_token_tree() {
581 let expansion = parse_to_token_tree_by_syntax(
582 r#"
583 #[derive(Copy)]
584 struct Foo;
585 "#,
586 );
587
588 assert_eq!(to_punct(&expansion.token_trees[0]).char, '#');
589 assert_eq!(
590 to_subtree(&expansion.token_trees[1]).delimiter_kind(),
591 Some(tt::DelimiterKind::Bracket)
592 );
593}
594
595#[test]
596fn test_two_idents() {
597 parse_macro(
598 r#"
599 macro_rules! foo {
600 ($ i:ident, $ j:ident) => {
601 fn foo() { let a = $ i; let b = $j; }
602 }
603 }
604"#,
605 )
606 .assert_expand_items("foo! { foo, bar }", "fn foo () {let a = foo ; let b = bar ;}");
607}
608
609#[test]
610fn test_tt_to_stmts() {
611 let stmts = parse_macro(
612 r#"
613 macro_rules! foo {
614 () => {
615 let a = 0;
616 a = 10 + 1;
617 a
618 }
619 }
620"#,
621 )
622 .expand_statements("foo!{}");
623
624 assert_eq!(
625 format!("{:#?}", stmts).trim(),
626 r#"[email protected]
627 [email protected]
628 [email protected] "let"
629 [email protected]
630 [email protected]
631 [email protected] "a"
632 [email protected] "="
633 [email protected]
634 [email protected] "0"
635 [email protected] ";"
636 [email protected]
637 [email protected]
638 [email protected]
639 [email protected]
640 [email protected]
641 [email protected]
642 [email protected] "a"
643 [email protected] "="
644 [email protected]
645 [email protected]
646 [email protected] "10"
647 [email protected] "+"
648 [email protected]
649 [email protected] "1"
650 [email protected] ";"
651 [email protected]
652 [email protected]
653 [email protected]
654 [email protected]
655 [email protected]
656 [email protected] "a""#,
657 );
658}
659
660#[test]
661fn test_match_literal() {
662 parse_macro(
663 r#"
664 macro_rules! foo {
665 ('(') => {
666 fn foo() {}
667 }
668 }
669"#,
670 )
671 .assert_expand_items("foo! ['('];", "fn foo () {}");
672}
673
674// The following tests are port from intellij-rust directly
675// https://github.com/intellij-rust/intellij-rust/blob/c4e9feee4ad46e7953b1948c112533360b6087bb/src/test/kotlin/org/rust/lang/core/macros/RsMacroExpansionTest.kt
676
677#[test]
678fn test_path() {
679 parse_macro(
680 r#"
681 macro_rules! foo {
682 ($ i:path) => {
683 fn foo() { let a = $ i; }
684 }
685 }
686"#,
687 )
688 .assert_expand_items("foo! { foo }", "fn foo () {let a = foo ;}")
689 .assert_expand_items(
690 "foo! { bar::<u8>::baz::<u8> }",
691 "fn foo () {let a = bar ::< u8 >:: baz ::< u8 > ;}",
692 );
693}
694
695#[test]
696fn test_two_paths() {
697 parse_macro(
698 r#"
699 macro_rules! foo {
700 ($ i:path, $ j:path) => {
701 fn foo() { let a = $ i; let b = $j; }
702 }
703 }
704"#,
705 )
706 .assert_expand_items("foo! { foo, bar }", "fn foo () {let a = foo ; let b = bar ;}");
707}
708
709#[test]
710fn test_path_with_path() {
711 parse_macro(
712 r#"
713 macro_rules! foo {
714 ($ i:path) => {
715 fn foo() { let a = $ i :: bar; }
716 }
717 }
718"#,
719 )
720 .assert_expand_items("foo! { foo }", "fn foo () {let a = foo :: bar ;}");
721}
722
723#[test]
724fn test_expr() {
725 parse_macro(
726 r#"
727 macro_rules! foo {
728 ($ i:expr) => {
729 fn bar() { $ i; }
730 }
731 }
732"#,
733 )
734 .assert_expand_items(
735 "foo! { 2 + 2 * baz(3).quux() }",
736 "fn bar () {2 + 2 * baz (3) . quux () ;}",
737 );
738}
739
740#[test]
741fn test_last_expr() {
742 parse_macro(
743 r#"
744 macro_rules! vec {
745 ($($item:expr),*) => {
746 {
747 let mut v = Vec::new();
748 $(
749 v.push($item);
750 )*
751 v
752 }
753 };
754 }
755"#,
756 )
757 .assert_expand_items(
758 "vec!(1,2,3);",
759 "{let mut v = Vec :: new () ; v . push (1) ; v . push (2) ; v . push (3) ; v}",
760 );
761}
762
763#[test]
764fn test_ty() {
765 parse_macro(
766 r#"
767 macro_rules! foo {
768 ($ i:ty) => (
769 fn bar() -> $ i { unimplemented!() }
770 )
771 }
772"#,
773 )
774 .assert_expand_items("foo! { Baz<u8> }", "fn bar () -> Baz < u8 > {unimplemented ! ()}");
775}
776
777#[test]
778fn test_ty_with_complex_type() {
779 parse_macro(
780 r#"
781 macro_rules! foo {
782 ($ i:ty) => (
783 fn bar() -> $ i { unimplemented!() }
784 )
785 }
786"#,
787 )
788 // Reference lifetime struct with generic type
789 .assert_expand_items(
790 "foo! { &'a Baz<u8> }",
791 "fn bar () -> & 'a Baz < u8 > {unimplemented ! ()}",
792 )
793 // extern "Rust" func type
794 .assert_expand_items(
795 r#"foo! { extern "Rust" fn() -> Ret }"#,
796 r#"fn bar () -> extern "Rust" fn () -> Ret {unimplemented ! ()}"#,
797 );
798}
799
800#[test]
801fn test_pat_() {
802 parse_macro(
803 r#"
804 macro_rules! foo {
805 ($ i:pat) => { fn foo() { let $ i; } }
806 }
807"#,
808 )
809 .assert_expand_items("foo! { (a, b) }", "fn foo () {let (a , b) ;}");
810}
811
812#[test]
813fn test_stmt() {
814 parse_macro(
815 r#"
816 macro_rules! foo {
817 ($ i:stmt) => (
818 fn bar() { $ i; }
819 )
820 }
821"#,
822 )
823 .assert_expand_items("foo! { 2 }", "fn bar () {2 ;}")
824 .assert_expand_items("foo! { let a = 0 }", "fn bar () {let a = 0 ;}");
825}
826
827#[test]
828fn test_single_item() {
829 parse_macro(
830 r#"
831 macro_rules! foo {
832 ($ i:item) => (
833 $ i
834 )
835 }
836"#,
837 )
838 .assert_expand_items("foo! {mod c {}}", "mod c {}");
839}
840
841#[test]
842fn test_all_items() {
843 parse_macro(
844 r#"
845 macro_rules! foo {
846 ($ ($ i:item)*) => ($ (
847 $ i
848 )*)
849 }
850"#,
851 ).
852 assert_expand_items(
853 r#"
854 foo! {
855 extern crate a;
856 mod b;
857 mod c {}
858 use d;
859 const E: i32 = 0;
860 static F: i32 = 0;
861 impl G {}
862 struct H;
863 enum I { Foo }
864 trait J {}
865 fn h() {}
866 extern {}
867 type T = u8;
868 }
869"#,
870 r#"extern crate a ; mod b ; mod c {} use d ; const E : i32 = 0 ; static F : i32 = 0 ; impl G {} struct H ; enum I {Foo} trait J {} fn h () {} extern {} type T = u8 ;"#,
871 );
872}
873
874#[test]
875fn test_block() {
876 parse_macro(
877 r#"
878 macro_rules! foo {
879 ($ i:block) => { fn foo() $ i }
880 }
881"#,
882 )
883 .assert_expand_statements("foo! { { 1; } }", "fn foo () {1 ;}");
884}
885
886#[test]
887fn test_meta() {
888 parse_macro(
889 r#"
890 macro_rules! foo {
891 ($ i:meta) => (
892 #[$ i]
893 fn bar() {}
894 )
895 }
896"#,
897 )
898 .assert_expand_items(
899 r#"foo! { cfg(target_os = "windows") }"#,
900 r#"# [cfg (target_os = "windows")] fn bar () {}"#,
901 );
902}
903
904#[test]
905fn test_meta_doc_comments() {
906 parse_macro(
907 r#"
908 macro_rules! foo {
909 ($(#[$ i:meta])+) => (
910 $(#[$ i])+
911 fn bar() {}
912 )
913 }
914"#,
915 ).
916 assert_expand_items(
917 r#"foo! {
918 /// Single Line Doc 1
919 /**
920 MultiLines Doc
921 */
922 }"#,
923 "# [doc = \" Single Line Doc 1\"] # [doc = \"\\\\n MultiLines Doc\\\\n \"] fn bar () {}",
924 );
925}
926
927#[test]
928fn test_tt_block() {
929 parse_macro(
930 r#"
931 macro_rules! foo {
932 ($ i:tt) => { fn foo() $ i }
933 }
934 "#,
935 )
936 .assert_expand_items(r#"foo! { { 1; } }"#, r#"fn foo () {1 ;}"#);
937}
938
939#[test]
940fn test_tt_group() {
941 parse_macro(
942 r#"
943 macro_rules! foo {
944 ($($ i:tt)*) => { $($ i)* }
945 }
946 "#,
947 )
948 .assert_expand_items(r#"foo! { fn foo() {} }"#, r#"fn foo () {}"#);
949}
950
951#[test]
952fn test_tt_composite() {
953 parse_macro(
954 r#"
955 macro_rules! foo {
956 ($i:tt) => { 0 }
957 }
958 "#,
959 )
960 .assert_expand_items(r#"foo! { => }"#, r#"0"#);
961}
962
963#[test]
964fn test_tt_composite2() {
965 let node = parse_macro(
966 r#"
967 macro_rules! foo {
968 ($($tt:tt)*) => { abs!(=> $($tt)*) }
969 }
970 "#,
971 )
972 .expand_items(r#"foo!{#}"#);
973
974 let res = format!("{:#?}", &node);
975 assert_eq_text!(
976 res.trim(),
977 r###"[email protected]
978 [email protected]
979 [email protected]
980 [email protected]
981 [email protected]
982 [email protected] "abs"
983 [email protected] "!"
984 [email protected]
985 [email protected] "("
986 [email protected] "="
987 [email protected] ">"
988 [email protected] " "
989 [email protected] "#"
990 [email protected] ")""###
991 );
992}
993
994#[test]
995fn test_lifetime() {
996 parse_macro(
997 r#"
998 macro_rules! foo {
999 ($ lt:lifetime) => { struct Ref<$ lt>{ s: &$ lt str } }
1000 }
1001"#,
1002 )
1003 .assert_expand_items(r#"foo!{'a}"#, r#"struct Ref <'a > {s : &'a str}"#);
1004}
1005
1006#[test]
1007fn test_literal() {
1008 parse_macro(
1009 r#"
1010 macro_rules! foo {
1011 ($ type:ty $ lit:literal) => { const VALUE: $ type = $ lit;};
1012 }
1013"#,
1014 )
1015 .assert_expand_items(r#"foo!(u8 0);"#, r#"const VALUE : u8 = 0 ;"#);
1016}
1017
1018#[test]
1019fn test_boolean_is_ident() {
1020 parse_macro(
1021 r#"
1022 macro_rules! foo {
1023 ($lit0:literal, $lit1:literal) => { const VALUE: (bool,bool) = ($lit0,$lit1); };
1024 }
1025"#,
1026 )
1027 .assert_expand(
1028 r#"foo!(true,false);"#,
1029 r#"
1030SUBTREE $
1031 IDENT const 14
1032 IDENT VALUE 15
1033 PUNCH : [alone] 16
1034 SUBTREE () 17
1035 IDENT bool 18
1036 PUNCH , [alone] 19
1037 IDENT bool 20
1038 PUNCH = [alone] 21
1039 SUBTREE () 22
1040 IDENT true 29
1041 PUNCH , [joint] 25
1042 IDENT false 31
1043 PUNCH ; [alone] 28
1044"#,
1045 );
1046}
1047
1048#[test]
1049fn test_vis() {
1050 parse_macro(
1051 r#"
1052 macro_rules! foo {
1053 ($ vis:vis $ name:ident) => { $ vis fn $ name() {}};
1054 }
1055"#,
1056 )
1057 .assert_expand_items(r#"foo!(pub foo);"#, r#"pub fn foo () {}"#)
1058 // test optional cases
1059 .assert_expand_items(r#"foo!(foo);"#, r#"fn foo () {}"#);
1060}
1061
1062#[test]
1063fn test_inner_macro_rules() {
1064 parse_macro(
1065 r#"
1066macro_rules! foo {
1067 ($a:ident, $b:ident, $c:tt) => {
1068
1069 macro_rules! bar {
1070 ($bi:ident) => {
1071 fn $bi() -> u8 {$c}
1072 }
1073 }
1074
1075 bar!($a);
1076 fn $b() -> u8 {$c}
1077 }
1078}
1079"#,
1080 ).
1081 assert_expand_items(
1082 r#"foo!(x,y, 1);"#,
1083 r#"macro_rules ! bar {($ bi : ident) => {fn $ bi () -> u8 {1}}} bar ! (x) ; fn y () -> u8 {1}"#,
1084 );
1085}
1086
1087// The following tests are based on real world situations
1088#[test]
1089fn test_vec() {
1090 let fixture = parse_macro(
1091 r#"
1092 macro_rules! vec {
1093 ($($item:expr),*) => {
1094 {
1095 let mut v = Vec::new();
1096 $(
1097 v.push($item);
1098 )*
1099 v
1100 }
1101 };
1102}
1103"#,
1104 );
1105 fixture
1106 .assert_expand_items(r#"vec!();"#, r#"{let mut v = Vec :: new () ; v}"#)
1107 .assert_expand_items(
1108 r#"vec![1u32,2];"#,
1109 r#"{let mut v = Vec :: new () ; v . push (1u32) ; v . push (2) ; v}"#,
1110 );
1111
1112 let tree = fixture.expand_expr(r#"vec![1u32,2];"#);
1113
1114 assert_eq!(
1115 format!("{:#?}", tree).trim(),
1116 r#"[email protected]
1117 [email protected] "{"
1118 [email protected]
1119 [email protected] "let"
1120 [email protected]
1121 [email protected] "mut"
1122 [email protected]
1123 [email protected] "v"
1124 [email protected] "="
1125 [email protected]
1126 [email protected]
1127 [email protected]
1128 [email protected]
1129 [email protected]
1130 [email protected]
1131 [email protected] "Vec"
1132 [email protected] "::"
1133 [email protected]
1134 [email protected]
1135 [email protected] "new"
1136 [email protected]
1137 [email protected] "("
1138 [email protected] ")"
1139 [email protected] ";"
1140 [email protected]
1141 [email protected]
1142 [email protected]
1143 [email protected]
1144 [email protected]
1145 [email protected]
1146 [email protected] "v"
1147 [email protected] "."
1148 [email protected]
1149 [email protected] "push"
1150 [email protected]
1151 [email protected] "("
1152 [email protected]
1153 [email protected] "1u32"
1154 [email protected] ")"
1155 [email protected] ";"
1156 [email protected]
1157 [email protected]
1158 [email protected]
1159 [email protected]
1160 [email protected]
1161 [email protected]
1162 [email protected] "v"
1163 [email protected] "."
1164 [email protected]
1165 [email protected] "push"
1166 [email protected]
1167 [email protected] "("
1168 [email protected]
1169 [email protected] "2"
1170 [email protected] ")"
1171 [email protected] ";"
1172 [email protected]
1173 [email protected]
1174 [email protected]
1175 [email protected]
1176 [email protected] "v"
1177 [email protected] "}""#
1178 );
1179}
1180
1181#[test]
1182fn test_winapi_struct() {
1183 // from https://github.com/retep998/winapi-rs/blob/a7ef2bca086aae76cf6c4ce4c2552988ed9798ad/src/macros.rs#L366
1184
1185 parse_macro(
1186 r#"
1187macro_rules! STRUCT {
1188 ($(#[$attrs:meta])* struct $name:ident {
1189 $($field:ident: $ftype:ty,)+
1190 }) => (
1191 #[repr(C)] #[derive(Copy)] $(#[$attrs])*
1192 pub struct $name {
1193 $(pub $field: $ftype,)+
1194 }
1195 impl Clone for $name {
1196 #[inline]
1197 fn clone(&self) -> $name { *self }
1198 }
1199 #[cfg(feature = "impl-default")]
1200 impl Default for $name {
1201 #[inline]
1202 fn default() -> $name { unsafe { $crate::_core::mem::zeroed() } }
1203 }
1204 );
1205}
1206"#,
1207 ).
1208 // from https://github.com/retep998/winapi-rs/blob/a7ef2bca086aae76cf6c4ce4c2552988ed9798ad/src/shared/d3d9caps.rs
1209 assert_expand_items(r#"STRUCT!{struct D3DVSHADERCAPS2_0 {Caps: u8,}}"#,
1210 "# [repr (C)] # [derive (Copy)] pub struct D3DVSHADERCAPS2_0 {pub Caps : u8 ,} impl Clone for D3DVSHADERCAPS2_0 {# [inline] fn clone (& self) -> D3DVSHADERCAPS2_0 {* self}} # [cfg (feature = \"impl-default\")] impl Default for D3DVSHADERCAPS2_0 {# [inline] fn default () -> D3DVSHADERCAPS2_0 {unsafe {$crate :: _core :: mem :: zeroed ()}}}"
1211 )
1212 .assert_expand_items(r#"STRUCT!{#[cfg_attr(target_arch = "x86", repr(packed))] struct D3DCONTENTPROTECTIONCAPS {Caps : u8 ,}}"#,
1213 "# [repr (C)] # [derive (Copy)] # [cfg_attr (target_arch = \"x86\" , repr (packed))] pub struct D3DCONTENTPROTECTIONCAPS {pub Caps : u8 ,} impl Clone for D3DCONTENTPROTECTIONCAPS {# [inline] fn clone (& self) -> D3DCONTENTPROTECTIONCAPS {* self}} # [cfg (feature = \"impl-default\")] impl Default for D3DCONTENTPROTECTIONCAPS {# [inline] fn default () -> D3DCONTENTPROTECTIONCAPS {unsafe {$crate :: _core :: mem :: zeroed ()}}}"
1214 );
1215}
1216
1217#[test]
1218fn test_int_base() {
1219 parse_macro(
1220 r#"
1221macro_rules! int_base {
1222 ($Trait:ident for $T:ident as $U:ident -> $Radix:ident) => {
1223 #[stable(feature = "rust1", since = "1.0.0")]
1224 impl fmt::$Trait for $T {
1225 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
1226 $Radix.fmt_int(*self as $U, f)
1227 }
1228 }
1229 }
1230}
1231"#,
1232 ).assert_expand_items(r#" int_base!{Binary for isize as usize -> Binary}"#,
1233 "# [stable (feature = \"rust1\" , since = \"1.0.0\")] impl fmt ::Binary for isize {fn fmt (& self , f : & mut fmt :: Formatter < \'_ >) -> fmt :: Result {Binary . fmt_int (* self as usize , f)}}"
1234 );
1235}
1236
1237#[test]
1238fn test_generate_pattern_iterators() {
1239 // from https://github.com/rust-lang/rust/blob/316a391dcb7d66dc25f1f9a4ec9d368ef7615005/src/libcore/str/mod.rs
1240 parse_macro(
1241 r#"
1242macro_rules! generate_pattern_iterators {
1243 { double ended; with $(#[$common_stability_attribute:meta])*,
1244 $forward_iterator:ident,
1245 $reverse_iterator:ident, $iterty:ty
1246 } => {
1247 fn foo(){}
1248 }
1249}
1250"#,
1251 ).assert_expand_items(
1252 r#"generate_pattern_iterators ! ( double ended ; with # [ stable ( feature = "rust1" , since = "1.0.0" ) ] , Split , RSplit , & 'a str );"#,
1253 "fn foo () {}",
1254 );
1255}
1256
1257#[test]
1258fn test_impl_fn_for_zst() {
1259 // from https://github.com/rust-lang/rust/blob/5d20ff4d2718c820632b38c1e49d4de648a9810b/src/libcore/internal_macros.rs
1260 parse_macro(
1261 r#"
1262macro_rules! impl_fn_for_zst {
1263 { $( $( #[$attr: meta] )*
1264 struct $Name: ident impl$( <$( $lifetime : lifetime ),+> )? Fn =
1265 |$( $arg: ident: $ArgTy: ty ),*| -> $ReturnTy: ty
1266$body: block; )+
1267 } => {
1268 $(
1269 $( #[$attr] )*
1270 struct $Name;
1271
1272 impl $( <$( $lifetime ),+> )? Fn<($( $ArgTy, )*)> for $Name {
1273 #[inline]
1274 extern "rust-call" fn call(&self, ($( $arg, )*): ($( $ArgTy, )*)) -> $ReturnTy {
1275 $body
1276 }
1277 }
1278
1279 impl $( <$( $lifetime ),+> )? FnMut<($( $ArgTy, )*)> for $Name {
1280 #[inline]
1281 extern "rust-call" fn call_mut(
1282 &mut self,
1283 ($( $arg, )*): ($( $ArgTy, )*)
1284 ) -> $ReturnTy {
1285 Fn::call(&*self, ($( $arg, )*))
1286 }
1287 }
1288
1289 impl $( <$( $lifetime ),+> )? FnOnce<($( $ArgTy, )*)> for $Name {
1290 type Output = $ReturnTy;
1291
1292 #[inline]
1293 extern "rust-call" fn call_once(self, ($( $arg, )*): ($( $ArgTy, )*)) -> $ReturnTy {
1294 Fn::call(&self, ($( $arg, )*))
1295 }
1296 }
1297 )+
1298}
1299 }
1300"#,
1301 ).assert_expand_items(r#"
1302impl_fn_for_zst ! {
1303 # [ derive ( Clone ) ]
1304 struct CharEscapeDebugContinue impl Fn = | c : char | -> char :: EscapeDebug {
1305 c . escape_debug_ext ( false )
1306 } ;
1307
1308 # [ derive ( Clone ) ]
1309 struct CharEscapeUnicode impl Fn = | c : char | -> char :: EscapeUnicode {
1310 c . escape_unicode ( )
1311 } ;
1312 # [ derive ( Clone ) ]
1313 struct CharEscapeDefault impl Fn = | c : char | -> char :: EscapeDefault {
1314 c . escape_default ( )
1315 } ;
1316 }
1317"#,
1318 "# [derive (Clone)] struct CharEscapeDebugContinue ; impl Fn < (char ,) > for CharEscapeDebugContinue {# [inline] extern \"rust-call\" fn call (& self , (c ,) : (char ,)) -> char :: EscapeDebug {{c . escape_debug_ext (false)}}} impl FnMut < (char ,) > for CharEscapeDebugContinue {# [inline] extern \"rust-call\" fn call_mut (& mut self , (c ,) : (char ,)) -> char :: EscapeDebug {Fn :: call (&* self , (c ,))}} impl FnOnce < (char ,) > for CharEscapeDebugContinue {type Output = char :: EscapeDebug ; # [inline] extern \"rust-call\" fn call_once (self , (c ,) : (char ,)) -> char :: EscapeDebug {Fn :: call (& self , (c ,))}} # [derive (Clone)] struct CharEscapeUnicode ; impl Fn < (char ,) > for CharEscapeUnicode {# [inline] extern \"rust-call\" fn call (& self , (c ,) : (char ,)) -> char :: EscapeUnicode {{c . escape_unicode ()}}} impl FnMut < (char ,) > for CharEscapeUnicode {# [inline] extern \"rust-call\" fn call_mut (& mut self , (c ,) : (char ,)) -> char :: EscapeUnicode {Fn :: call (&* self , (c ,))}} impl FnOnce < (char ,) > for CharEscapeUnicode {type Output = char :: EscapeUnicode ; # [inline] extern \"rust-call\" fn call_once (self , (c ,) : (char ,)) -> char :: EscapeUnicode {Fn :: call (& self , (c ,))}} # [derive (Clone)] struct CharEscapeDefault ; impl Fn < (char ,) > for CharEscapeDefault {# [inline] extern \"rust-call\" fn call (& self , (c ,) : (char ,)) -> char :: EscapeDefault {{c . escape_default ()}}} impl FnMut < (char ,) > for CharEscapeDefault {# [inline] extern \"rust-call\" fn call_mut (& mut self , (c ,) : (char ,)) -> char :: EscapeDefault {Fn :: call (&* self , (c ,))}} impl FnOnce < (char ,) > for CharEscapeDefault {type Output = char :: EscapeDefault ; # [inline] extern \"rust-call\" fn call_once (self , (c ,) : (char ,)) -> char :: EscapeDefault {Fn :: call (& self , (c ,))}}"
1319 );
1320}
1321
1322#[test]
1323fn test_impl_nonzero_fmt() {
1324 // from https://github.com/rust-lang/rust/blob/316a391dcb7d66dc25f1f9a4ec9d368ef7615005/src/libcore/num/mod.rs#L12
1325 parse_macro(
1326 r#"
1327 macro_rules! impl_nonzero_fmt {
1328 ( #[$stability: meta] ( $( $Trait: ident ),+ ) for $Ty: ident ) => {
1329 fn foo () {}
1330 }
1331 }
1332"#,
1333 ).assert_expand_items(
1334 r#"impl_nonzero_fmt! { # [stable(feature= "nonzero",since="1.28.0")] (Debug,Display,Binary,Octal,LowerHex,UpperHex) for NonZeroU8}"#,
1335 "fn foo () {}",
1336 );
1337}
1338
1339#[test]
1340fn test_cfg_if_items() {
1341 // from https://github.com/rust-lang/rust/blob/33fe1131cadba69d317156847be9a402b89f11bb/src/libstd/macros.rs#L986
1342 parse_macro(
1343 r#"
1344 macro_rules! __cfg_if_items {
1345 (($($not:meta,)*) ; ) => {};
1346 (($($not:meta,)*) ; ( ($($m:meta),*) ($($it:item)*) ), $($rest:tt)*) => {
1347 __cfg_if_items! { ($($not,)* $($m,)*) ; $($rest)* }
1348 }
1349 }
1350"#,
1351 ).assert_expand_items(
1352 r#"__cfg_if_items ! { ( rustdoc , ) ; ( ( ) ( # [ cfg ( any ( target_os = "redox" , unix ) ) ] # [ stable ( feature = "rust1" , since = "1.0.0" ) ] pub use sys :: ext as unix ; # [ cfg ( windows ) ] # [ stable ( feature = "rust1" , since = "1.0.0" ) ] pub use sys :: ext as windows ; # [ cfg ( any ( target_os = "linux" , target_os = "l4re" ) ) ] pub mod linux ; ) ) , }"#,
1353 "__cfg_if_items ! {(rustdoc ,) ;}",
1354 );
1355}
1356
1357#[test]
1358fn test_cfg_if_main() {
1359 // from https://github.com/rust-lang/rust/blob/3d211248393686e0f73851fc7548f6605220fbe1/src/libpanic_unwind/macros.rs#L9
1360 parse_macro(
1361 r#"
1362 macro_rules! cfg_if {
1363 ($(
1364 if #[cfg($($meta:meta),*)] { $($it:item)* }
1365 ) else * else {
1366 $($it2:item)*
1367 }) => {
1368 __cfg_if_items! {
1369 () ;
1370 $( ( ($($meta),*) ($($it)*) ), )*
1371 ( () ($($it2)*) ),
1372 }
1373 };
1374
1375 // Internal macro to Apply a cfg attribute to a list of items
1376 (@__apply $m:meta, $($it:item)*) => {
1377 $(#[$m] $it)*
1378 };
1379 }
1380"#,
1381 ).assert_expand_items(r#"
1382cfg_if ! {
1383 if # [ cfg ( target_env = "msvc" ) ] {
1384 // no extra unwinder support needed
1385 } else if # [ cfg ( all ( target_arch = "wasm32" , not ( target_os = "emscripten" ) ) ) ] {
1386 // no unwinder on the system!
1387 } else {
1388 mod libunwind ;
1389 pub use libunwind :: * ;
1390 }
1391 }
1392"#,
1393 "__cfg_if_items ! {() ; ((target_env = \"msvc\") ()) , ((all (target_arch = \"wasm32\" , not (target_os = \"emscripten\"))) ()) , (() (mod libunwind ; pub use libunwind :: * ;)) ,}"
1394 ).assert_expand_items(
1395 r#"
1396cfg_if ! { @ __apply cfg ( all ( not ( any ( not ( any ( target_os = "solaris" , target_os = "illumos" ) ) ) ) ) ) , }
1397"#,
1398 "",
1399 );
1400}
1401
1402#[test]
1403fn test_proptest_arbitrary() {
1404 // from https://github.com/AltSysrq/proptest/blob/d1c4b049337d2f75dd6f49a095115f7c532e5129/proptest/src/arbitrary/macros.rs#L16
1405 parse_macro(
1406 r#"
1407macro_rules! arbitrary {
1408 ([$($bounds : tt)*] $typ: ty, $strat: ty, $params: ty;
1409 $args: ident => $logic: expr) => {
1410 impl<$($bounds)*> $crate::arbitrary::Arbitrary for $typ {
1411 type Parameters = $params;
1412 type Strategy = $strat;
1413 fn arbitrary_with($args: Self::Parameters) -> Self::Strategy {
1414 $logic
1415 }
1416 }
1417 };
1418
1419}"#,
1420 ).assert_expand_items(r#"arbitrary ! ( [ A : Arbitrary ]
1421 Vec < A > ,
1422 VecStrategy < A :: Strategy > ,
1423 RangedParams1 < A :: Parameters > ;
1424 args => { let product_unpack ! [ range , a ] = args ; vec ( any_with :: < A > ( a ) , range ) }
1425 ) ;"#,
1426 "impl <A : Arbitrary > $crate :: arbitrary :: Arbitrary for Vec < A > {type Parameters = RangedParams1 < A :: Parameters > ; type Strategy = VecStrategy < A :: Strategy > ; fn arbitrary_with (args : Self :: Parameters) -> Self :: Strategy {{let product_unpack ! [range , a] = args ; vec (any_with :: < A > (a) , range)}}}"
1427 );
1428}
1429
1430#[test]
1431fn test_old_ridl() {
1432 // This is from winapi 2.8, which do not have a link from github
1433 //
1434 let expanded = parse_macro(
1435 r#"
1436#[macro_export]
1437macro_rules! RIDL {
1438 (interface $interface:ident ($vtbl:ident) : $pinterface:ident ($pvtbl:ident)
1439 {$(
1440 fn $method:ident(&mut self $(,$p:ident : $t:ty)*) -> $rtr:ty
1441 ),+}
1442 ) => {
1443 impl $interface {
1444 $(pub unsafe fn $method(&mut self) -> $rtr {
1445 ((*self.lpVtbl).$method)(self $(,$p)*)
1446 })+
1447 }
1448 };
1449}"#,
1450 ).expand_tt(r#"
1451 RIDL!{interface ID3D11Asynchronous(ID3D11AsynchronousVtbl): ID3D11DeviceChild(ID3D11DeviceChildVtbl) {
1452 fn GetDataSize(&mut self) -> UINT
1453 }}"#);
1454
1455 assert_eq!(expanded.to_string(), "impl ID3D11Asynchronous {pub unsafe fn GetDataSize (& mut self) -> UINT {((* self . lpVtbl) .GetDataSize) (self)}}");
1456}
1457
1458#[test]
1459fn test_quick_error() {
1460 let expanded = parse_macro(
1461 r#"
1462macro_rules! quick_error {
1463
1464 (SORT [enum $name:ident $( #[$meta:meta] )*]
1465 items [$($( #[$imeta:meta] )*
1466 => $iitem:ident: $imode:tt [$( $ivar:ident: $ityp:ty ),*]
1467 {$( $ifuncs:tt )*} )* ]
1468 buf [ ]
1469 queue [ ]
1470 ) => {
1471 quick_error!(ENUMINITION [enum $name $( #[$meta] )*]
1472 body []
1473 queue [$(
1474 $( #[$imeta] )*
1475 =>
1476 $iitem: $imode [$( $ivar: $ityp ),*]
1477 )*]
1478 );
1479};
1480
1481}
1482"#,
1483 )
1484 .expand_tt(
1485 r#"
1486quick_error ! (SORT [enum Wrapped # [derive (Debug)]] items [
1487 => One : UNIT [] {}
1488 => Two : TUPLE [s :String] {display ("two: {}" , s) from ()}
1489 ] buf [] queue []) ;
1490"#,
1491 );
1492
1493 assert_eq!(expanded.to_string(), "quick_error ! (ENUMINITION [enum Wrapped # [derive (Debug)]] body [] queue [=> One : UNIT [] => Two : TUPLE [s : String]]) ;");
1494}
1495
1496#[test]
1497fn test_empty_repeat_vars_in_empty_repeat_vars() {
1498 parse_macro(
1499 r#"
1500macro_rules! delegate_impl {
1501 ([$self_type:ident, $self_wrap:ty, $self_map:ident]
1502 pub trait $name:ident $(: $sup:ident)* $(+ $more_sup:ident)* {
1503
1504 // "Escaped" associated types. Stripped before making the `trait`
1505 // itself, but forwarded when delegating impls.
1506 $(
1507 @escape [type $assoc_name_ext:ident]
1508 // Associated types. Forwarded.
1509 )*
1510 $(
1511 @section type
1512 $(
1513 $(#[$_assoc_attr:meta])*
1514 type $assoc_name:ident $(: $assoc_bound:ty)*;
1515 )+
1516 )*
1517 // Methods. Forwarded. Using $self_map!(self) around the self argument.
1518 // Methods must use receiver `self` or explicit type like `self: &Self`
1519 // &self and &mut self are _not_ supported.
1520 $(
1521 @section self
1522 $(
1523 $(#[$_method_attr:meta])*
1524 fn $method_name:ident(self $(: $self_selftype:ty)* $(,$marg:ident : $marg_ty:ty)*) -> $mret:ty;
1525 )+
1526 )*
1527 // Arbitrary tail that is ignored when forwarding.
1528 $(
1529 @section nodelegate
1530 $($tail:tt)*
1531 )*
1532 }) => {
1533 impl<> $name for $self_wrap where $self_type: $name {
1534 $(
1535 $(
1536 fn $method_name(self $(: $self_selftype)* $(,$marg: $marg_ty)*) -> $mret {
1537 $self_map!(self).$method_name($($marg),*)
1538 }
1539 )*
1540 )*
1541 }
1542 }
1543}
1544"#,
1545 ).assert_expand_items(
1546 r#"delegate_impl ! {[G , & 'a mut G , deref] pub trait Data : GraphBase {@ section type type NodeWeight ;}}"#,
1547 "impl <> Data for & \'a mut G where G : Data {}",
1548 );
1549}
1550
1551#[test]
1552fn expr_interpolation() {
1553 let expanded = parse_macro(
1554 r#"
1555 macro_rules! id {
1556 ($expr:expr) => {
1557 map($expr)
1558 }
1559 }
1560 "#,
1561 )
1562 .expand_expr("id!(x + foo);");
1563
1564 assert_eq!(expanded.to_string(), "map(x+foo)");
1565}
1566
1567pub(crate) struct MacroFixture {
1568 rules: MacroRules,
1569}
1570
1571impl MacroFixture {
1572 pub(crate) fn expand_tt(&self, invocation: &str) -> tt::Subtree {
1573 self.try_expand_tt(invocation).unwrap()
1574 }
1575
1576 fn try_expand_tt(&self, invocation: &str) -> Result<tt::Subtree, ExpandError> {
1577 let source_file = ast::SourceFile::parse(invocation).tree();
1578 let macro_invocation =
1579 source_file.syntax().descendants().find_map(ast::MacroCall::cast).unwrap();
1580
1581 let (invocation_tt, _) = ast_to_token_tree(&macro_invocation.token_tree().unwrap())
1582 .ok_or_else(|| ExpandError::ConversionError)?;
1583
1584 self.rules.expand(&invocation_tt).result()
1585 }
1586
1587 fn assert_expand_err(&self, invocation: &str, err: &ExpandError) {
1588 assert_eq!(self.try_expand_tt(invocation).as_ref(), Err(err));
1589 }
1590
1591 fn expand_items(&self, invocation: &str) -> SyntaxNode {
1592 let expanded = self.expand_tt(invocation);
1593 token_tree_to_syntax_node(&expanded, FragmentKind::Items).unwrap().0.syntax_node()
1594 }
1595
1596 fn expand_statements(&self, invocation: &str) -> SyntaxNode {
1597 let expanded = self.expand_tt(invocation);
1598 token_tree_to_syntax_node(&expanded, FragmentKind::Statements).unwrap().0.syntax_node()
1599 }
1600
1601 fn expand_expr(&self, invocation: &str) -> SyntaxNode {
1602 let expanded = self.expand_tt(invocation);
1603 token_tree_to_syntax_node(&expanded, FragmentKind::Expr).unwrap().0.syntax_node()
1604 }
1605
1606 fn assert_expand_tt(&self, invocation: &str, expected: &str) {
1607 let expansion = self.expand_tt(invocation);
1608 assert_eq!(expansion.to_string(), expected);
1609 }
1610
1611 fn assert_expand(&self, invocation: &str, expected: &str) {
1612 let expansion = self.expand_tt(invocation);
1613 let actual = format!("{:?}", expansion);
1614 test_utils::assert_eq_text!(&actual.trim(), &expected.trim());
1615 }
1616
1617 fn assert_expand_items(&self, invocation: &str, expected: &str) -> &MacroFixture {
1618 self.assert_expansion(FragmentKind::Items, invocation, expected);
1619 self
1620 }
1621
1622 fn assert_expand_statements(&self, invocation: &str, expected: &str) -> &MacroFixture {
1623 self.assert_expansion(FragmentKind::Statements, invocation, expected);
1624 self
1625 }
1626
1627 fn assert_expansion(&self, kind: FragmentKind, invocation: &str, expected: &str) {
1628 let expanded = self.expand_tt(invocation);
1629 assert_eq!(expanded.to_string(), expected);
1630
1631 let expected = expected.replace("$crate", "C_C__C");
1632
1633 // wrap the given text to a macro call
1634 let expected = {
1635 let wrapped = format!("wrap_macro!( {} )", expected);
1636 let wrapped = ast::SourceFile::parse(&wrapped);
1637 let wrapped =
1638 wrapped.tree().syntax().descendants().find_map(ast::TokenTree::cast).unwrap();
1639 let mut wrapped = ast_to_token_tree(&wrapped).unwrap().0;
1640 wrapped.delimiter = None;
1641 wrapped
1642 };
1643
1644 let expanded_tree = token_tree_to_syntax_node(&expanded, kind).unwrap().0.syntax_node();
1645 let expanded_tree = debug_dump_ignore_spaces(&expanded_tree).trim().to_string();
1646
1647 let expected_tree = token_tree_to_syntax_node(&expected, kind).unwrap().0.syntax_node();
1648 let expected_tree = debug_dump_ignore_spaces(&expected_tree).trim().to_string();
1649
1650 let expected_tree = expected_tree.replace("C_C__C", "$crate");
1651 assert_eq!(
1652 expanded_tree, expected_tree,
1653 "\nleft:\n{}\nright:\n{}",
1654 expanded_tree, expected_tree,
1655 );
1656 }
1657}
1658
1659fn parse_macro_to_tt(ra_fixture: &str) -> tt::Subtree {
1660 let source_file = ast::SourceFile::parse(ra_fixture).ok().unwrap();
1661 let macro_definition =
1662 source_file.syntax().descendants().find_map(ast::MacroCall::cast).unwrap();
1663
1664 let (definition_tt, _) = ast_to_token_tree(&macro_definition.token_tree().unwrap()).unwrap();
1665
1666 let parsed = parse_to_token_tree(
1667 &ra_fixture[macro_definition.token_tree().unwrap().syntax().text_range()],
1668 )
1669 .unwrap()
1670 .0;
1671 assert_eq!(definition_tt, parsed);
1672
1673 definition_tt
1674}
1675
1676pub(crate) fn parse_macro(ra_fixture: &str) -> MacroFixture {
1677 let definition_tt = parse_macro_to_tt(ra_fixture);
1678 let rules = MacroRules::parse(&definition_tt).unwrap();
1679 MacroFixture { rules }
1680}
1681
1682pub(crate) fn parse_macro_error(ra_fixture: &str) -> ParseError {
1683 let definition_tt = parse_macro_to_tt(ra_fixture);
1684
1685 match MacroRules::parse(&definition_tt) {
1686 Ok(_) => panic!("Expect error"),
1687 Err(err) => err,
1688 }
1689}
1690
1691pub(crate) fn parse_to_token_tree_by_syntax(ra_fixture: &str) -> tt::Subtree {
1692 let source_file = ast::SourceFile::parse(ra_fixture).ok().unwrap();
1693 let tt = syntax_node_to_token_tree(source_file.syntax()).unwrap().0;
1694
1695 let parsed = parse_to_token_tree(ra_fixture).unwrap().0;
1696 assert_eq!(tt, parsed);
1697
1698 parsed
1699}
1700
1701fn debug_dump_ignore_spaces(node: &syntax::SyntaxNode) -> String {
1702 let mut level = 0;
1703 let mut buf = String::new();
1704 macro_rules! indent {
1705 () => {
1706 for _ in 0..level {
1707 buf.push_str(" ");
1708 }
1709 };
1710 }
1711
1712 for event in node.preorder_with_tokens() {
1713 match event {
1714 WalkEvent::Enter(element) => {
1715 match element {
1716 NodeOrToken::Node(node) => {
1717 indent!();
1718 writeln!(buf, "{:?}", node.kind()).unwrap();
1719 }
1720 NodeOrToken::Token(token) => match token.kind() {
1721 syntax::SyntaxKind::WHITESPACE => {}
1722 _ => {
1723 indent!();
1724 writeln!(buf, "{:?}", token.kind()).unwrap();
1725 }
1726 },
1727 }
1728 level += 1;
1729 }
1730 WalkEvent::Leave(_) => level -= 1,
1731 }
1732 }
1733
1734 buf
1735}
1736
1737#[test]
1738fn test_issue_2520() {
1739 let macro_fixture = parse_macro(
1740 r#"
1741 macro_rules! my_macro {
1742 {
1743 ( $(
1744 $( [] $sname:ident : $stype:ty )?
1745 $( [$expr:expr] $nname:ident : $ntype:ty )?
1746 ),* )
1747 } => {
1748 Test {
1749 $(
1750 $( $sname, )?
1751 )*
1752 }
1753 };
1754 }
1755 "#,
1756 );
1757
1758 macro_fixture.assert_expand_items(
1759 r#"my_macro ! {
1760 ([] p1 : u32 , [|_| S0K0] s : S0K0 , [] k0 : i32)
1761 }"#,
1762 "Test {p1 , k0 ,}",
1763 );
1764}
1765
1766#[test]
1767fn test_issue_3861() {
1768 let macro_fixture = parse_macro(
1769 r#"
1770 macro_rules! rgb_color {
1771 ($p:expr, $t: ty) => {
1772 pub fn new() {
1773 let _ = 0 as $t << $p;
1774 }
1775 };
1776 }
1777 "#,
1778 );
1779
1780 macro_fixture.expand_items(r#"rgb_color!(8 + 8, u32);"#);
1781}
1782
1783#[test]
1784fn test_repeat_bad_var() {
1785 // FIXME: the second rule of the macro should be removed and an error about
1786 // `$( $c )+` raised
1787 parse_macro(
1788 r#"
1789 macro_rules! foo {
1790 ($( $b:ident )+) => {
1791 $( $c )+
1792 };
1793 ($( $b:ident )+) => {
1794 $( $b )+
1795 }
1796 }
1797 "#,
1798 )
1799 .assert_expand_items("foo!(b0 b1);", "b0 b1");
1800}
1801
1802#[test]
1803fn test_no_space_after_semi_colon() {
1804 let expanded = parse_macro(
1805 r#"
1806 macro_rules! with_std { ($($i:item)*) => ($(#[cfg(feature = "std")]$i)*) }
1807 "#,
1808 )
1809 .expand_items(r#"with_std! {mod m;mod f;}"#);
1810
1811 let dump = format!("{:#?}", expanded);
1812 assert_eq_text!(
1813 dump.trim(),
1814 r###"[email protected]
1815 [email protected]
1816 [email protected]
1817 [email protected] "#"
1818 [email protected] "["
1819 [email protected]
1820 [email protected]
1821 [email protected]
1822 [email protected] "cfg"
1823 [email protected]
1824 [email protected] "("
1825 [email protected] "feature"
1826 [email protected] "="
1827 [email protected] "\"std\""
1828 [email protected] ")"
1829 [email protected] "]"
1830 [email protected] "mod"
1831 [email protected]
1832 [email protected] "m"
1833 [email protected] ";"
1834 [email protected]
1835 [email protected]
1836 [email protected] "#"
1837 [email protected] "["
1838 [email protected]
1839 [email protected]
1840 [email protected]
1841 [email protected] "cfg"
1842 [email protected]
1843 [email protected] "("
1844 [email protected] "feature"
1845 [email protected] "="
1846 [email protected] "\"std\""
1847 [email protected] ")"
1848 [email protected] "]"
1849 [email protected] "mod"
1850 [email protected]
1851 [email protected] "f"
1852 [email protected] ";""###,
1853 );
1854}
1855
1856// https://github.com/rust-lang/rust/blob/master/src/test/ui/issues/issue-57597.rs
1857#[test]
1858fn test_rustc_issue_57597() {
1859 fn test_error(fixture: &str) {
1860 assert_eq!(parse_macro_error(fixture), ParseError::RepetitionEmtpyTokenTree);
1861 }
1862
1863 test_error("macro_rules! foo { ($($($i:ident)?)+) => {}; }");
1864 test_error("macro_rules! foo { ($($($i:ident)?)*) => {}; }");
1865 test_error("macro_rules! foo { ($($($i:ident)?)?) => {}; }");
1866 test_error("macro_rules! foo { ($($($($i:ident)?)?)?) => {}; }");
1867 test_error("macro_rules! foo { ($($($($i:ident)*)?)?) => {}; }");
1868 test_error("macro_rules! foo { ($($($($i:ident)?)*)?) => {}; }");
1869 test_error("macro_rules! foo { ($($($($i:ident)?)?)*) => {}; }");
1870 test_error("macro_rules! foo { ($($($($i:ident)*)*)?) => {}; }");
1871 test_error("macro_rules! foo { ($($($($i:ident)?)*)*) => {}; }");
1872 test_error("macro_rules! foo { ($($($($i:ident)?)*)+) => {}; }");
1873 test_error("macro_rules! foo { ($($($($i:ident)+)?)*) => {}; }");
1874 test_error("macro_rules! foo { ($($($($i:ident)+)*)?) => {}; }");
1875}
1876
1877#[test]
1878fn test_expand_bad_literal() {
1879 parse_macro(
1880 r#"
1881 macro_rules! foo { ($i:literal) => {}; }
1882 "#,
1883 )
1884 .assert_expand_err(r#"foo!(&k");"#, &ExpandError::BindingError("".into()));
1885}
1886
1887#[test]
1888fn test_empty_comments() {
1889 parse_macro(
1890 r#"
1891 macro_rules! one_arg_macro { ($fmt:expr) => (); }
1892 "#,
1893 )
1894 .assert_expand_err(
1895 r#"one_arg_macro!(/**/)"#,
1896 &ExpandError::BindingError("expected Expr".into()),
1897 );
1898}
diff --git a/crates/mbe/src/tt_iter.rs b/crates/mbe/src/tt_iter.rs
new file mode 100644
index 000000000..46c420718
--- /dev/null
+++ b/crates/mbe/src/tt_iter.rs
@@ -0,0 +1,75 @@
1//! FIXME: write short doc here
2
3#[derive(Debug, Clone)]
4pub(crate) struct TtIter<'a> {
5 pub(crate) inner: std::slice::Iter<'a, tt::TokenTree>,
6}
7
8impl<'a> TtIter<'a> {
9 pub(crate) fn new(subtree: &'a tt::Subtree) -> TtIter<'a> {
10 TtIter { inner: subtree.token_trees.iter() }
11 }
12
13 pub(crate) fn expect_char(&mut self, char: char) -> Result<(), ()> {
14 match self.next() {
15 Some(tt::TokenTree::Leaf(tt::Leaf::Punct(tt::Punct { char: c, .. }))) if *c == char => {
16 Ok(())
17 }
18 _ => Err(()),
19 }
20 }
21
22 pub(crate) fn expect_subtree(&mut self) -> Result<&'a tt::Subtree, ()> {
23 match self.next() {
24 Some(tt::TokenTree::Subtree(it)) => Ok(it),
25 _ => Err(()),
26 }
27 }
28
29 pub(crate) fn expect_leaf(&mut self) -> Result<&'a tt::Leaf, ()> {
30 match self.next() {
31 Some(tt::TokenTree::Leaf(it)) => Ok(it),
32 _ => Err(()),
33 }
34 }
35
36 pub(crate) fn expect_ident(&mut self) -> Result<&'a tt::Ident, ()> {
37 match self.expect_leaf()? {
38 tt::Leaf::Ident(it) => Ok(it),
39 _ => Err(()),
40 }
41 }
42
43 pub(crate) fn expect_literal(&mut self) -> Result<&'a tt::Leaf, ()> {
44 let it = self.expect_leaf()?;
45 match it {
46 tt::Leaf::Literal(_) => Ok(it),
47 tt::Leaf::Ident(ident) if ident.text == "true" || ident.text == "false" => Ok(it),
48 _ => Err(()),
49 }
50 }
51
52 pub(crate) fn expect_punct(&mut self) -> Result<&'a tt::Punct, ()> {
53 match self.expect_leaf()? {
54 tt::Leaf::Punct(it) => Ok(it),
55 _ => Err(()),
56 }
57 }
58
59 pub(crate) fn peek_n(&self, n: usize) -> Option<&tt::TokenTree> {
60 self.inner.as_slice().get(n)
61 }
62}
63
64impl<'a> Iterator for TtIter<'a> {
65 type Item = &'a tt::TokenTree;
66 fn next(&mut self) -> Option<Self::Item> {
67 self.inner.next()
68 }
69
70 fn size_hint(&self) -> (usize, Option<usize>) {
71 self.inner.size_hint()
72 }
73}
74
75impl<'a> std::iter::ExactSizeIterator for TtIter<'a> {}
generated by cgit v1.2.3 (git 2.25.1) at 2024-07-01 08:35:48 +0100