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-rw-r--r--crates/ra_mbe/src/subtree_source.rs366
1 files changed, 166 insertions, 200 deletions
diff --git a/crates/ra_mbe/src/subtree_source.rs b/crates/ra_mbe/src/subtree_source.rs
index 4b37c2bda..0a070b46a 100644
--- a/crates/ra_mbe/src/subtree_source.rs
+++ b/crates/ra_mbe/src/subtree_source.rs
@@ -2,6 +2,64 @@ use ra_parser::{TokenSource};
2use ra_syntax::{classify_literal, SmolStr, SyntaxKind, SyntaxKind::*}; 2use ra_syntax::{classify_literal, SmolStr, SyntaxKind, SyntaxKind::*};
3use std::cell::{RefCell}; 3use std::cell::{RefCell};
4 4
5// A Sequece of Token,
6#[derive(Debug, Clone, Eq, PartialEq)]
7pub(super) enum TokenSeq<'a> {
8 Subtree(&'a tt::Subtree),
9 Seq(&'a [tt::TokenTree]),
10}
11
12impl<'a> From<&'a tt::Subtree> for TokenSeq<'a> {
13 fn from(s: &'a tt::Subtree) -> TokenSeq<'a> {
14 TokenSeq::Subtree(s)
15 }
16}
17
18impl<'a> From<&'a [tt::TokenTree]> for TokenSeq<'a> {
19 fn from(s: &'a [tt::TokenTree]) -> TokenSeq<'a> {
20 TokenSeq::Seq(s)
21 }
22}
23
24enum DelimToken<'a> {
25 Delim(&'a tt::Delimiter, bool),
26 Token(&'a tt::TokenTree),
27 End,
28}
29
30impl<'a> TokenSeq<'a> {
31 fn get(&self, pos: usize) -> DelimToken<'a> {
32 match self {
33 TokenSeq::Subtree(subtree) => {
34 let len = subtree.token_trees.len() + 2;
35 match pos {
36 p if p >= len => DelimToken::End,
37 p if p == len - 1 => DelimToken::Delim(&subtree.delimiter, true),
38 0 => DelimToken::Delim(&subtree.delimiter, false),
39 p => DelimToken::Token(&subtree.token_trees[p - 1]),
40 }
41 }
42 TokenSeq::Seq(tokens) => {
43 tokens.get(pos).map(DelimToken::Token).unwrap_or(DelimToken::End)
44 }
45 }
46 }
47
48 fn len(&self) -> usize {
49 match self {
50 TokenSeq::Subtree(subtree) => subtree.token_trees.len() + 2,
51 TokenSeq::Seq(tokens) => tokens.len(),
52 }
53 }
54
55 fn child_slice(&self) -> &[tt::TokenTree] {
56 match self {
57 TokenSeq::Subtree(subtree) => &subtree.token_trees,
58 TokenSeq::Seq(tokens) => &tokens,
59 }
60 }
61}
62
5#[derive(Debug, Clone, Eq, PartialEq)] 63#[derive(Debug, Clone, Eq, PartialEq)]
6struct TtToken { 64struct TtToken {
7 pub kind: SyntaxKind, 65 pub kind: SyntaxKind,
@@ -12,29 +70,27 @@ struct TtToken {
12 70
13#[derive(Debug, Clone, Eq, PartialEq)] 71#[derive(Debug, Clone, Eq, PartialEq)]
14enum WalkCursor { 72enum WalkCursor {
15 DelimiterBegin(Option<TtToken>), 73 Token(usize, TtToken),
16 Token(usize, Option<TtToken>),
17 DelimiterEnd(Option<TtToken>),
18 Eof, 74 Eof,
19} 75}
20 76
21#[derive(Debug)] 77#[derive(Debug)]
22struct SubTreeWalker<'a> { 78struct SubTreeWalker<'a> {
23 pos: usize, 79 pos: usize,
24 stack: Vec<(&'a tt::Subtree, Option<usize>)>, 80 stack: Vec<(TokenSeq<'a>, usize)>,
25 cursor: WalkCursor, 81 cursor: WalkCursor,
26 last_steps: Vec<usize>, 82 last_steps: Vec<usize>,
27 subtree: &'a tt::Subtree, 83 ts: TokenSeq<'a>,
28} 84}
29 85
30impl<'a> SubTreeWalker<'a> { 86impl<'a> SubTreeWalker<'a> {
31 fn new(subtree: &tt::Subtree) -> SubTreeWalker { 87 fn new(ts: TokenSeq<'a>) -> SubTreeWalker {
32 let mut res = SubTreeWalker { 88 let mut res = SubTreeWalker {
33 pos: 0, 89 pos: 0,
34 stack: vec![], 90 stack: vec![],
35 cursor: WalkCursor::Eof, 91 cursor: WalkCursor::Eof,
36 last_steps: vec![], 92 last_steps: vec![],
37 subtree, 93 ts,
38 }; 94 };
39 95
40 res.reset(); 96 res.reset();
@@ -47,209 +103,108 @@ impl<'a> SubTreeWalker<'a> {
47 103
48 fn reset(&mut self) { 104 fn reset(&mut self) {
49 self.pos = 0; 105 self.pos = 0;
50 self.stack = vec![(self.subtree, None)]; 106 self.stack = vec![];
51 self.cursor = WalkCursor::DelimiterBegin(convert_delim(self.subtree.delimiter, false));
52 self.last_steps = vec![]; 107 self.last_steps = vec![];
53 108
54 while self.is_empty_delimiter() { 109 self.cursor = match self.ts.get(0) {
55 self.forward_unchecked(); 110 DelimToken::Token(token) => match token {
56 } 111 tt::TokenTree::Subtree(subtree) => {
57 } 112 let ts = TokenSeq::from(subtree);
58 113 self.stack.push((ts, 0));
59 // This funciton will fast forward the cursor, 114 WalkCursor::Token(0, convert_delim(subtree.delimiter, false))
60 // Such that backward will stop at `start_pos` point 115 }
61 fn start_from_nth(&mut self, start_pos: usize) { 116 tt::TokenTree::Leaf(leaf) => {
62 self.reset(); 117 let next_tokens = self.ts.child_slice();
63 self.pos = start_pos; 118 WalkCursor::Token(0, convert_leaf(&next_tokens, leaf))
64 self.cursor = self.walk_token(start_pos, 0, false); 119 }
65 120 },
66 while self.is_empty_delimiter() { 121 DelimToken::Delim(delim, is_end) => {
67 self.forward_unchecked(); 122 assert!(!is_end);
123 WalkCursor::Token(0, convert_delim(*delim, false))
124 }
125 DelimToken::End => WalkCursor::Eof,
68 } 126 }
69 } 127 }
70 128
71 fn current(&self) -> Option<&TtToken> { 129 fn current(&self) -> Option<&TtToken> {
72 match &self.cursor { 130 match &self.cursor {
73 WalkCursor::DelimiterBegin(t) => t.as_ref(), 131 WalkCursor::Token(_, t) => Some(t),
74 WalkCursor::Token(_, t) => t.as_ref(),
75 WalkCursor::DelimiterEnd(t) => t.as_ref(),
76 WalkCursor::Eof => None, 132 WalkCursor::Eof => None,
77 } 133 }
78 } 134 }
79 135
80 fn is_empty_delimiter(&self) -> bool { 136 fn top(&self) -> &TokenSeq {
81 match &self.cursor { 137 self.stack.last().map(|(t, _)| t).unwrap_or(&self.ts)
82 WalkCursor::DelimiterBegin(None) => true,
83 WalkCursor::DelimiterEnd(None) => true,
84 _ => false,
85 }
86 } 138 }
87 139
88 /// Move cursor backward by 1 step with empty checking 140 /// Move cursor backward by 1 step
89 fn backward(&mut self) { 141 fn backward(&mut self) {
90 if self.last_steps.is_empty() { 142 if self.last_steps.is_empty() {
91 return; 143 return;
92 } 144 }
145
93 self.pos -= 1; 146 self.pos -= 1;
94 loop { 147 let last_step = self.last_steps.pop().unwrap();
95 self.backward_unchecked();
96 // Skip Empty delimiter
97 if self.last_steps.is_empty() || !self.is_empty_delimiter() {
98 break;
99 }
100 }
101 148
102 // Move forward if it is empty delimiter 149 self.cursor = match self.cursor {
103 if self.last_steps.is_empty() { 150 WalkCursor::Token(idx, _) => self.walk_token(idx, last_step, true),
104 while self.is_empty_delimiter() { 151 WalkCursor::Eof => {
105 self.forward_unchecked(); 152 let len = self.top().len();
153 self.walk_token(len, last_step, true)
106 } 154 }
107 } 155 }
108 } 156 }
109 157
110 /// Move cursor backward by 1 step without empty check 158 /// Move cursor forward by 1 step
111 ///
112 /// Depends on the current state of cursor:
113 ///
114 /// * Delimiter Begin => Pop the stack, goto last walking token (`walk_token`)
115 /// * Token => Goto prev token (`walk_token`)
116 /// * Delimiter End => Goto the last child token (`walk_token`)
117 /// * Eof => push the root subtree, and set it as Delimiter End
118 fn backward_unchecked(&mut self) {
119 if self.last_steps.is_empty() {
120 return;
121 }
122
123 let last_step = self.last_steps.pop().unwrap();
124 let do_walk_token = match self.cursor {
125 WalkCursor::DelimiterBegin(_) => None,
126 WalkCursor::Token(u, _) => Some(u),
127 WalkCursor::DelimiterEnd(_) => {
128 let (top, _) = self.stack.last().unwrap();
129 Some(top.token_trees.len())
130 }
131 WalkCursor::Eof => None,
132 };
133
134 self.cursor = match do_walk_token {
135 Some(u) => self.walk_token(u, last_step, true),
136 None => match self.cursor {
137 WalkCursor::Eof => {
138 self.stack.push((self.subtree, None));
139 WalkCursor::DelimiterEnd(convert_delim(
140 self.stack.last().unwrap().0.delimiter,
141 true,
142 ))
143 }
144 _ => {
145 let (_, last_top_cursor) = self.stack.pop().unwrap();
146 assert!(!self.stack.is_empty());
147
148 self.walk_token(last_top_cursor.unwrap(), last_step, true)
149 }
150 },
151 };
152 }
153
154 /// Move cursor forward by 1 step with empty checking
155 fn forward(&mut self) { 159 fn forward(&mut self) {
156 if self.is_eof() { 160 if self.is_eof() {
157 return; 161 return;
158 } 162 }
159
160 self.pos += 1; 163 self.pos += 1;
161 loop {
162 self.forward_unchecked();
163 if !self.is_empty_delimiter() {
164 break;
165 }
166 }
167 }
168
169 /// Move cursor forward by 1 step without empty checking
170 ///
171 /// Depends on the current state of cursor:
172 ///
173 /// * Delimiter Begin => Goto the first child token (`walk_token`)
174 /// * Token => Goto next token (`walk_token`)
175 /// * Delimiter End => Pop the stack, goto last walking token (`walk_token`)
176 ///
177 fn forward_unchecked(&mut self) {
178 if self.is_eof() {
179 return;
180 }
181 164
182 let step = self.current().map(|x| x.n_tokens).unwrap_or(1); 165 let step = self.current().map(|x| x.n_tokens).unwrap_or(1);
183 self.last_steps.push(step); 166 self.last_steps.push(step);
184 167
185 let do_walk_token = match self.cursor { 168 if let WalkCursor::Token(u, _) = self.cursor {
186 WalkCursor::DelimiterBegin(_) => Some((0, 0)), 169 self.cursor = self.walk_token(u, step, false)
187 WalkCursor::Token(u, _) => Some((u, step)), 170 }
188 WalkCursor::DelimiterEnd(_) => None,
189 _ => unreachable!(),
190 };
191
192 self.cursor = match do_walk_token {
193 Some((u, step)) => self.walk_token(u, step, false),
194 None => {
195 let (_, last_top_idx) = self.stack.pop().unwrap();
196 match self.stack.last() {
197 Some(_) => self.walk_token(last_top_idx.unwrap(), 1, false),
198 None => WalkCursor::Eof,
199 }
200 }
201 };
202 } 171 }
203 172
204 /// Traversal child token 173 /// Traversal child token
205 /// Depends on the new position, it returns:
206 ///
207 /// * new position < 0 => DelimiterBegin
208 /// * new position > token_tree.len() => DelimiterEnd
209 /// * if new position is a subtree, depends on traversal direction:
210 /// ** backward => DelimiterEnd
211 /// ** forward => DelimiterBegin
212 /// * if new psoition is a leaf, return walk_leaf()
213 fn walk_token(&mut self, pos: usize, offset: usize, backward: bool) -> WalkCursor { 174 fn walk_token(&mut self, pos: usize, offset: usize, backward: bool) -> WalkCursor {
214 let (top, _) = self.stack.last().unwrap(); 175 let top = self.stack.last().map(|(t, _)| t).unwrap_or(&self.ts);
215 176
216 if backward && pos < offset { 177 if backward && pos < offset {
217 return WalkCursor::DelimiterBegin(convert_delim( 178 let (_, last_idx) = self.stack.pop().unwrap();
218 self.stack.last().unwrap().0.delimiter, 179 return self.walk_token(last_idx, offset, backward);
219 false,
220 ));
221 }
222
223 if !backward && pos + offset >= top.token_trees.len() {
224 return WalkCursor::DelimiterEnd(convert_delim(
225 self.stack.last().unwrap().0.delimiter,
226 true,
227 ));
228 } 180 }
229 181
230 let pos = if backward { pos - offset } else { pos + offset }; 182 let pos = if backward { pos - offset } else { pos + offset };
231 183
232 match &top.token_trees[pos] { 184 match top.get(pos) {
233 tt::TokenTree::Subtree(subtree) => { 185 DelimToken::Token(token) => match token {
234 self.stack.push((subtree, Some(pos))); 186 tt::TokenTree::Subtree(subtree) => {
235 let delim = convert_delim(self.stack.last().unwrap().0.delimiter, backward); 187 let ts = TokenSeq::from(subtree);
236 if backward { 188 let new_idx = if backward { ts.len() - 1 } else { 0 };
237 WalkCursor::DelimiterEnd(delim) 189 self.stack.push((ts, pos));
238 } else { 190 WalkCursor::Token(new_idx, convert_delim(subtree.delimiter, backward))
239 WalkCursor::DelimiterBegin(delim) 191 }
192 tt::TokenTree::Leaf(leaf) => {
193 let next_tokens = top.child_slice();
194 WalkCursor::Token(pos, convert_leaf(&next_tokens[pos..], leaf))
240 } 195 }
196 },
197 DelimToken::Delim(delim, is_end) => {
198 WalkCursor::Token(pos, convert_delim(*delim, is_end))
241 } 199 }
242 tt::TokenTree::Leaf(leaf) => WalkCursor::Token(pos, Some(self.walk_leaf(leaf, pos))), 200 DelimToken::End => {
243 } 201 // it is the top level
244 } 202 if let Some((_, last_idx)) = self.stack.pop() {
245 203 assert!(!backward);
246 fn walk_leaf(&mut self, leaf: &tt::Leaf, pos: usize) -> TtToken { 204 self.walk_token(last_idx, offset, backward)
247 match leaf { 205 } else {
248 tt::Leaf::Literal(l) => convert_literal(l), 206 WalkCursor::Eof
249 tt::Leaf::Ident(ident) => convert_ident(ident), 207 }
250 tt::Leaf::Punct(punct) => {
251 let (top, _) = self.stack.last().unwrap();
252 convert_punct(punct, top, pos)
253 } 208 }
254 } 209 }
255 } 210 }
@@ -263,27 +218,20 @@ pub(crate) trait Querier {
263#[derive(Debug)] 218#[derive(Debug)]
264pub(crate) struct WalkerOwner<'a> { 219pub(crate) struct WalkerOwner<'a> {
265 walker: RefCell<SubTreeWalker<'a>>, 220 walker: RefCell<SubTreeWalker<'a>>,
266 offset: usize,
267} 221}
268 222
269impl<'a> WalkerOwner<'a> { 223impl<'a> WalkerOwner<'a> {
270 fn new(subtree: &'a tt::Subtree) -> Self { 224 fn new<I: Into<TokenSeq<'a>>>(ts: I) -> Self {
271 WalkerOwner { walker: RefCell::new(SubTreeWalker::new(subtree)), offset: 0 } 225 WalkerOwner { walker: RefCell::new(SubTreeWalker::new(ts.into())) }
272 } 226 }
273 227
274 fn get<'b>(&self, pos: usize) -> Option<TtToken> { 228 fn get<'b>(&self, pos: usize) -> Option<TtToken> {
275 self.set_walker_pos(pos); 229 self.set_pos(pos);
276 let walker = self.walker.borrow(); 230 let walker = self.walker.borrow();
277 walker.current().cloned() 231 walker.current().cloned()
278 } 232 }
279 233
280 fn start_from_nth(&mut self, pos: usize) { 234 fn set_pos(&self, pos: usize) {
281 self.offset = pos;
282 self.walker.borrow_mut().start_from_nth(pos);
283 }
284
285 fn set_walker_pos(&self, mut pos: usize) {
286 pos += self.offset;
287 let mut walker = self.walker.borrow_mut(); 235 let mut walker = self.walker.borrow_mut();
288 while pos > walker.pos && !walker.is_eof() { 236 while pos > walker.pos && !walker.is_eof() {
289 walker.forward(); 237 walker.forward();
@@ -294,19 +242,26 @@ impl<'a> WalkerOwner<'a> {
294 } 242 }
295 243
296 fn collect_token_trees(&mut self, n: usize) -> Vec<&tt::TokenTree> { 244 fn collect_token_trees(&mut self, n: usize) -> Vec<&tt::TokenTree> {
297 self.start_from_nth(self.offset);
298
299 let mut res = vec![]; 245 let mut res = vec![];
300 let mut walker = self.walker.borrow_mut(); 246 let mut walker = self.walker.borrow_mut();
247 walker.reset();
301 248
302 while walker.pos - self.offset < n { 249 while walker.pos < n {
303 if let WalkCursor::Token(u, tt) = &walker.cursor { 250 if let WalkCursor::Token(u, tt) = &walker.cursor {
304 if walker.stack.len() == 1 { 251 // We only collect the topmost child
305 // We only collect the topmost child 252 if walker.stack.len() == 0 {
306 res.push(&walker.stack[0].0.token_trees[*u]); 253 for i in 0..tt.n_tokens {
307 if let Some(tt) = tt { 254 if let DelimToken::Token(token) = walker.ts.get(u + i) {
308 for i in 0..tt.n_tokens - 1 { 255 res.push(token);
309 res.push(&walker.stack[0].0.token_trees[u + i]); 256 }
257 }
258 } else if walker.stack.len() == 1 {
259 if let DelimToken::Delim(_, is_end) = walker.top().get(*u) {
260 if !is_end {
261 let (_, last_idx) = &walker.stack[0];
262 if let DelimToken::Token(token) = walker.ts.get(*last_idx) {
263 res.push(token);
264 }
310 } 265 }
311 } 266 }
312 } 267 }
@@ -331,12 +286,8 @@ pub(crate) struct SubtreeTokenSource<'a> {
331} 286}
332 287
333impl<'a> SubtreeTokenSource<'a> { 288impl<'a> SubtreeTokenSource<'a> {
334 pub fn new(subtree: &tt::Subtree) -> SubtreeTokenSource { 289 pub fn new<I: Into<TokenSeq<'a>>>(ts: I) -> SubtreeTokenSource<'a> {
335 SubtreeTokenSource { walker: WalkerOwner::new(subtree) } 290 SubtreeTokenSource { walker: WalkerOwner::new(ts) }
336 }
337
338 pub fn start_from_nth(&mut self, n: usize) {
339 self.walker.start_from_nth(n);
340 } 291 }
341 292
342 pub fn querier<'b>(&'a self) -> &'b WalkerOwner<'a> 293 pub fn querier<'b>(&'a self) -> &'b WalkerOwner<'a>
@@ -361,10 +312,16 @@ impl<'a> TokenSource for SubtreeTokenSource<'a> {
361 } 312 }
362 } 313 }
363 fn is_token_joint_to_next(&self, pos: usize) -> bool { 314 fn is_token_joint_to_next(&self, pos: usize) -> bool {
364 self.walker.get(pos).unwrap().is_joint_to_next 315 match self.walker.get(pos) {
316 Some(t) => t.is_joint_to_next,
317 _ => false,
318 }
365 } 319 }
366 fn is_keyword(&self, pos: usize, kw: &str) -> bool { 320 fn is_keyword(&self, pos: usize, kw: &str) -> bool {
367 self.walker.get(pos).unwrap().text == *kw 321 match self.walker.get(pos) {
322 Some(t) => t.text == *kw,
323 _ => false,
324 }
368 } 325 }
369} 326}
370 327
@@ -467,18 +424,18 @@ where
467 None 424 None
468} 425}
469 426
470fn convert_delim(d: tt::Delimiter, closing: bool) -> Option<TtToken> { 427fn convert_delim(d: tt::Delimiter, closing: bool) -> TtToken {
471 let (kinds, texts) = match d { 428 let (kinds, texts) = match d {
472 tt::Delimiter::Parenthesis => ([L_PAREN, R_PAREN], "()"), 429 tt::Delimiter::Parenthesis => ([L_PAREN, R_PAREN], "()"),
473 tt::Delimiter::Brace => ([L_CURLY, R_CURLY], "{}"), 430 tt::Delimiter::Brace => ([L_CURLY, R_CURLY], "{}"),
474 tt::Delimiter::Bracket => ([L_BRACK, R_BRACK], "[]"), 431 tt::Delimiter::Bracket => ([L_BRACK, R_BRACK], "[]"),
475 tt::Delimiter::None => return None, 432 tt::Delimiter::None => ([L_DOLLAR, R_DOLLAR], ""),
476 }; 433 };
477 434
478 let idx = closing as usize; 435 let idx = closing as usize;
479 let kind = kinds[idx]; 436 let kind = kinds[idx];
480 let text = &texts[idx..texts.len() - (1 - idx)]; 437 let text = if texts.len() > 0 { &texts[idx..texts.len() - (1 - idx)] } else { "" };
481 Some(TtToken { kind, is_joint_to_next: false, text: SmolStr::new(text), n_tokens: 1 }) 438 TtToken { kind, is_joint_to_next: false, text: SmolStr::new(text), n_tokens: 1 }
482} 439}
483 440
484fn convert_literal(l: &tt::Literal) -> TtToken { 441fn convert_literal(l: &tt::Literal) -> TtToken {
@@ -495,8 +452,9 @@ fn convert_ident(ident: &tt::Ident) -> TtToken {
495 TtToken { kind, is_joint_to_next: false, text: ident.text.clone(), n_tokens: 1 } 452 TtToken { kind, is_joint_to_next: false, text: ident.text.clone(), n_tokens: 1 }
496} 453}
497 454
498fn convert_punct(p: &tt::Punct, parent: &tt::Subtree, next: usize) -> TtToken { 455fn convert_punct(p: &tt::Punct, next_tokens: &[tt::TokenTree]) -> TtToken {
499 let iter = parent.token_trees[next + 1..].iter(); 456 let mut iter = next_tokens.iter();
457 iter.next();
500 let mut peek = TokenPeek::new(iter); 458 let mut peek = TokenPeek::new(iter);
501 459
502 if let Some((kind, is_joint_to_next, text, size)) = convert_multi_char_punct(p, &mut peek) { 460 if let Some((kind, is_joint_to_next, text, size)) = convert_multi_char_punct(p, &mut peek) {
@@ -519,3 +477,11 @@ fn convert_punct(p: &tt::Punct, parent: &tt::Subtree, next: usize) -> TtToken {
519 TtToken { kind, is_joint_to_next: p.spacing == tt::Spacing::Joint, text, n_tokens: 1 } 477 TtToken { kind, is_joint_to_next: p.spacing == tt::Spacing::Joint, text, n_tokens: 1 }
520 } 478 }
521} 479}
480
481fn convert_leaf(tokens: &[tt::TokenTree], leaf: &tt::Leaf) -> TtToken {
482 match leaf {
483 tt::Leaf::Literal(l) => convert_literal(l),
484 tt::Leaf::Ident(ident) => convert_ident(ident),
485 tt::Leaf::Punct(punct) => convert_punct(punct, tokens),
486 }
487}