diff options
Diffstat (limited to 'crates/ra_syntax/src/validation.rs')
-rw-r--r-- | crates/ra_syntax/src/validation.rs | 58 |
1 files changed, 58 insertions, 0 deletions
diff --git a/crates/ra_syntax/src/validation.rs b/crates/ra_syntax/src/validation.rs index 5e93895ec..f0b3dec63 100644 --- a/crates/ra_syntax/src/validation.rs +++ b/crates/ra_syntax/src/validation.rs | |||
@@ -96,6 +96,7 @@ pub(crate) fn validate(root: &SyntaxNode) -> Vec<SyntaxError> { | |||
96 | ast::RecordField(it) => validate_numeric_name(it.name_ref(), &mut errors), | 96 | ast::RecordField(it) => validate_numeric_name(it.name_ref(), &mut errors), |
97 | ast::Visibility(it) => validate_visibility(it, &mut errors), | 97 | ast::Visibility(it) => validate_visibility(it, &mut errors), |
98 | ast::RangeExpr(it) => validate_range_expr(it, &mut errors), | 98 | ast::RangeExpr(it) => validate_range_expr(it, &mut errors), |
99 | ast::PathSegment(it) => validate_crate_keyword_in_path_segment(it, &mut errors), | ||
99 | _ => (), | 100 | _ => (), |
100 | } | 101 | } |
101 | } | 102 | } |
@@ -222,3 +223,60 @@ fn validate_range_expr(expr: ast::RangeExpr, errors: &mut Vec<SyntaxError>) { | |||
222 | )); | 223 | )); |
223 | } | 224 | } |
224 | } | 225 | } |
226 | |||
227 | fn validate_crate_keyword_in_path_segment( | ||
228 | segment: ast::PathSegment, | ||
229 | errors: &mut Vec<SyntaxError>, | ||
230 | ) { | ||
231 | const ERR_MSG: &str = "The `crate` keyword is only allowed as the first segment of a path"; | ||
232 | |||
233 | let crate_token = match segment.crate_token() { | ||
234 | None => return, | ||
235 | Some(it) => it, | ||
236 | }; | ||
237 | |||
238 | // Disallow both ::crate and foo::crate | ||
239 | let mut path = segment.parent_path(); | ||
240 | if segment.coloncolon_token().is_some() || path.qualifier().is_some() { | ||
241 | errors.push(SyntaxError::new(ERR_MSG, crate_token.text_range())); | ||
242 | return; | ||
243 | } | ||
244 | |||
245 | // For expressions and types, validation is complete, but we still have | ||
246 | // to handle invalid UseItems like this: | ||
247 | // | ||
248 | // use foo:{crate::bar::baz}; | ||
249 | // | ||
250 | // To handle this we must inspect the parent `UseItem`s and `UseTree`s | ||
251 | // but right now we're looking deep inside the nested `Path` nodes because | ||
252 | // `Path`s are left-associative: | ||
253 | // | ||
254 | // ((crate)::bar)::baz) | ||
255 | // ^ current value of path | ||
256 | // | ||
257 | // So we need to climb to the top | ||
258 | while let Some(parent) = path.parent_path() { | ||
259 | path = parent; | ||
260 | } | ||
261 | |||
262 | // Now that we've found the whole path we need to see if there's a prefix | ||
263 | // somewhere in the UseTree hierarchy. This check is arbitrarily deep | ||
264 | // because rust allows arbitrary nesting like so: | ||
265 | // | ||
266 | // use {foo::{{{{crate::bar::baz}}}}}; | ||
267 | for node in path.syntax().ancestors().skip(1) { | ||
268 | match_ast! { | ||
269 | match node { | ||
270 | ast::UseTree(it) => if let Some(tree_path) = it.path() { | ||
271 | // Even a top-level path exists within a `UseTree` so we must explicitly | ||
272 | // allow our path but disallow anything else | ||
273 | if tree_path != path { | ||
274 | errors.push(SyntaxError::new(ERR_MSG, crate_token.text_range())); | ||
275 | } | ||
276 | }, | ||
277 | ast::UseTreeList(_it) => continue, | ||
278 | _ => return, | ||
279 | } | ||
280 | }; | ||
281 | } | ||
282 | } | ||