diff options
author | Jeremy A. Kolb <[email protected]> | 2018-10-09 15:08:17 +0100 |
---|---|---|
committer | Jeremy A. Kolb <[email protected]> | 2018-10-11 21:40:46 +0100 |
commit | f8a2b533045757c42c206b2596448baf4737f1f0 (patch) | |
tree | 587e681ec5323d8deabcc6d533de033e7aa79be7 /crates/ra_analysis/src/imp.rs | |
parent | 2ba6f18586d02a6dbc32e0bea88f7b4236277ea1 (diff) |
Language Server: textDocument/signatureHelp
Implements a pretty barebones function signature help mechanism in
the language server.
Users can use `Analysis::resolve_callback()` to get basic information
about a call site.
Fixes #102
Diffstat (limited to 'crates/ra_analysis/src/imp.rs')
-rw-r--r-- | crates/ra_analysis/src/imp.rs | 114 |
1 files changed, 110 insertions, 4 deletions
diff --git a/crates/ra_analysis/src/imp.rs b/crates/ra_analysis/src/imp.rs index 47bc0032b..9e3ae2b03 100644 --- a/crates/ra_analysis/src/imp.rs +++ b/crates/ra_analysis/src/imp.rs | |||
@@ -12,19 +12,18 @@ use relative_path::RelativePath; | |||
12 | use rustc_hash::FxHashSet; | 12 | use rustc_hash::FxHashSet; |
13 | use ra_editor::{self, FileSymbol, LineIndex, find_node_at_offset, LocalEdit, resolve_local_name}; | 13 | use ra_editor::{self, FileSymbol, LineIndex, find_node_at_offset, LocalEdit, resolve_local_name}; |
14 | use ra_syntax::{ | 14 | use ra_syntax::{ |
15 | TextUnit, TextRange, SmolStr, File, AstNode, | 15 | TextUnit, TextRange, SmolStr, File, AstNode, SyntaxNodeRef, |
16 | SyntaxKind::*, | 16 | SyntaxKind::*, |
17 | ast::{self, NameOwner}, | 17 | ast::{self, NameOwner, ArgListOwner, Expr}, |
18 | }; | 18 | }; |
19 | 19 | ||
20 | use { | 20 | use { |
21 | FileId, FileResolver, Query, Diagnostic, SourceChange, SourceFileEdit, Position, FileSystemEdit, | 21 | FileId, FileResolver, Query, Diagnostic, SourceChange, SourceFileEdit, Position, FileSystemEdit, |
22 | JobToken, CrateGraph, CrateId, | 22 | JobToken, CrateGraph, CrateId, |
23 | roots::{SourceRoot, ReadonlySourceRoot, WritableSourceRoot}, | 23 | roots::{SourceRoot, ReadonlySourceRoot, WritableSourceRoot}, |
24 | descriptors::{ModuleTreeDescriptor, Problem}, | 24 | descriptors::{FnDescriptor, ModuleTreeDescriptor, Problem}, |
25 | }; | 25 | }; |
26 | 26 | ||
27 | |||
28 | #[derive(Clone, Debug)] | 27 | #[derive(Clone, Debug)] |
29 | pub(crate) struct FileResolverImp { | 28 | pub(crate) struct FileResolverImp { |
30 | inner: Arc<FileResolver> | 29 | inner: Arc<FileResolver> |
@@ -306,6 +305,70 @@ impl AnalysisImpl { | |||
306 | .collect() | 305 | .collect() |
307 | } | 306 | } |
308 | 307 | ||
308 | pub fn resolve_callable(&self, file_id: FileId, offset: TextUnit, token: &JobToken) | ||
309 | -> Option<(FnDescriptor, Option<usize>)> { | ||
310 | |||
311 | let root = self.root(file_id); | ||
312 | let file = root.syntax(file_id); | ||
313 | let syntax = file.syntax(); | ||
314 | |||
315 | // Find the calling expression and it's NameRef | ||
316 | let calling_node = FnCallNode::with_node(syntax, offset)?; | ||
317 | let name_ref = calling_node.name_ref()?; | ||
318 | |||
319 | // Resolve the function's NameRef (NOTE: this isn't entirely accurate). | ||
320 | let file_symbols = self.index_resolve(name_ref, token); | ||
321 | for (_, fs) in file_symbols { | ||
322 | if fs.kind == FN_DEF { | ||
323 | if let Some(fn_def) = find_node_at_offset(syntax, fs.node_range.start()) { | ||
324 | let descriptor = FnDescriptor::new(fn_def); | ||
325 | |||
326 | // If we have a calling expression let's find which argument we are on | ||
327 | let mut current_parameter = None; | ||
328 | |||
329 | let num_params = descriptor.params.len(); | ||
330 | let has_self = fn_def.param_list() | ||
331 | .and_then(|l| l.self_param()) | ||
332 | .is_some(); | ||
333 | |||
334 | |||
335 | if num_params == 1 { | ||
336 | if !has_self { | ||
337 | current_parameter = Some(1); | ||
338 | } | ||
339 | } | ||
340 | else if num_params > 1 { | ||
341 | // Count how many parameters into the call we are. | ||
342 | // TODO: This is best effort for now and should be fixed at some point. | ||
343 | // It may be better to see where we are in the arg_list and then check | ||
344 | // where offset is in that list (or beyond). | ||
345 | // Revisit this after we get documentation comments in. | ||
346 | if let Some(ref arg_list) = calling_node.arg_list() { | ||
347 | let start = arg_list.syntax().range().start(); | ||
348 | |||
349 | let range_search = TextRange::from_to(start, offset); | ||
350 | let mut commas : usize = arg_list.syntax().text() | ||
351 | .slice(range_search).to_string() | ||
352 | .matches(",") | ||
353 | .count(); | ||
354 | |||
355 | // If we have a method call eat the first param since it's just self. | ||
356 | if has_self { | ||
357 | commas = commas + 1; | ||
358 | } | ||
359 | |||
360 | current_parameter = Some(commas); | ||
361 | } | ||
362 | } | ||
363 | |||
364 | return Some((descriptor, current_parameter)); | ||
365 | } | ||
366 | } | ||
367 | } | ||
368 | |||
369 | None | ||
370 | } | ||
371 | |||
309 | fn index_resolve(&self, name_ref: ast::NameRef, token: &JobToken) -> Vec<(FileId, FileSymbol)> { | 372 | fn index_resolve(&self, name_ref: ast::NameRef, token: &JobToken) -> Vec<(FileId, FileSymbol)> { |
310 | let name = name_ref.text(); | 373 | let name = name_ref.text(); |
311 | let mut query = Query::new(name.to_string()); | 374 | let mut query = Query::new(name.to_string()); |
@@ -355,3 +418,46 @@ impl CrateGraph { | |||
355 | Some(crate_id) | 418 | Some(crate_id) |
356 | } | 419 | } |
357 | } | 420 | } |
421 | |||
422 | enum FnCallNode<'a> { | ||
423 | CallExpr(ast::CallExpr<'a>), | ||
424 | MethodCallExpr(ast::MethodCallExpr<'a>) | ||
425 | } | ||
426 | |||
427 | impl<'a> FnCallNode<'a> { | ||
428 | pub fn with_node(syntax: SyntaxNodeRef, offset: TextUnit) -> Option<FnCallNode> { | ||
429 | if let Some(expr) = find_node_at_offset::<ast::CallExpr>(syntax, offset) { | ||
430 | return Some(FnCallNode::CallExpr(expr)); | ||
431 | } | ||
432 | if let Some(expr) = find_node_at_offset::<ast::MethodCallExpr>(syntax, offset) { | ||
433 | return Some(FnCallNode::MethodCallExpr(expr)); | ||
434 | } | ||
435 | None | ||
436 | } | ||
437 | |||
438 | pub fn name_ref(&self) -> Option<ast::NameRef> { | ||
439 | match *self { | ||
440 | FnCallNode::CallExpr(call_expr) => { | ||
441 | Some(match call_expr.expr()? { | ||
442 | Expr::PathExpr(path_expr) => { | ||
443 | path_expr.path()?.segment()?.name_ref()? | ||
444 | }, | ||
445 | _ => return None | ||
446 | }) | ||
447 | }, | ||
448 | |||
449 | FnCallNode::MethodCallExpr(call_expr) => { | ||
450 | call_expr.syntax().children() | ||
451 | .filter_map(ast::NameRef::cast) | ||
452 | .nth(0) | ||
453 | } | ||
454 | } | ||
455 | } | ||
456 | |||
457 | pub fn arg_list(&self) -> Option<ast::ArgList> { | ||
458 | match *self { | ||
459 | FnCallNode::CallExpr(expr) => expr.arg_list(), | ||
460 | FnCallNode::MethodCallExpr(expr) => expr.arg_list() | ||
461 | } | ||
462 | } | ||
463 | } \ No newline at end of file | ||