diff options
Diffstat (limited to 'crates/ra_hir/src/attr.rs')
-rw-r--r-- | crates/ra_hir/src/attr.rs | 80 |
1 files changed, 80 insertions, 0 deletions
diff --git a/crates/ra_hir/src/attr.rs b/crates/ra_hir/src/attr.rs new file mode 100644 index 000000000..f67e80bfd --- /dev/null +++ b/crates/ra_hir/src/attr.rs | |||
@@ -0,0 +1,80 @@ | |||
1 | //! A higher level attributes based on TokenTree, with also some shortcuts. | ||
2 | |||
3 | use std::sync::Arc; | ||
4 | |||
5 | use mbe::ast_to_token_tree; | ||
6 | use ra_cfg::CfgOptions; | ||
7 | use ra_syntax::{ | ||
8 | ast::{self, AstNode, AttrsOwner}, | ||
9 | SmolStr, | ||
10 | }; | ||
11 | use tt::Subtree; | ||
12 | |||
13 | use crate::{db::AstDatabase, path::Path, HirFileId, Source}; | ||
14 | |||
15 | #[derive(Debug, Clone, PartialEq, Eq)] | ||
16 | pub(crate) struct Attr { | ||
17 | pub(crate) path: Path, | ||
18 | pub(crate) input: Option<AttrInput>, | ||
19 | } | ||
20 | |||
21 | #[derive(Debug, Clone, PartialEq, Eq)] | ||
22 | pub enum AttrInput { | ||
23 | Literal(SmolStr), | ||
24 | TokenTree(Subtree), | ||
25 | } | ||
26 | |||
27 | impl Attr { | ||
28 | pub(crate) fn from_src( | ||
29 | Source { file_id, ast }: Source<ast::Attr>, | ||
30 | db: &impl AstDatabase, | ||
31 | ) -> Option<Attr> { | ||
32 | let path = Path::from_src(Source { file_id, ast: ast.path()? }, db)?; | ||
33 | let input = match ast.input() { | ||
34 | None => None, | ||
35 | Some(ast::AttrInput::Literal(lit)) => { | ||
36 | // FIXME: escape? raw string? | ||
37 | let value = lit.syntax().first_token()?.text().trim_matches('"').into(); | ||
38 | Some(AttrInput::Literal(value)) | ||
39 | } | ||
40 | Some(ast::AttrInput::TokenTree(tt)) => { | ||
41 | Some(AttrInput::TokenTree(ast_to_token_tree(&tt)?.0)) | ||
42 | } | ||
43 | }; | ||
44 | |||
45 | Some(Attr { path, input }) | ||
46 | } | ||
47 | |||
48 | pub(crate) fn from_attrs_owner( | ||
49 | file_id: HirFileId, | ||
50 | owner: &dyn AttrsOwner, | ||
51 | db: &impl AstDatabase, | ||
52 | ) -> Option<Arc<[Attr]>> { | ||
53 | let mut attrs = owner.attrs().peekable(); | ||
54 | if attrs.peek().is_none() { | ||
55 | // Avoid heap allocation | ||
56 | return None; | ||
57 | } | ||
58 | Some(attrs.flat_map(|ast| Attr::from_src(Source { file_id, ast }, db)).collect()) | ||
59 | } | ||
60 | |||
61 | pub(crate) fn is_simple_atom(&self, name: &str) -> bool { | ||
62 | // FIXME: Avoid cloning | ||
63 | self.path.as_ident().map_or(false, |s| s.to_string() == name) | ||
64 | } | ||
65 | |||
66 | pub(crate) fn as_cfg(&self) -> Option<&Subtree> { | ||
67 | if self.is_simple_atom("cfg") { | ||
68 | match &self.input { | ||
69 | Some(AttrInput::TokenTree(subtree)) => Some(subtree), | ||
70 | _ => None, | ||
71 | } | ||
72 | } else { | ||
73 | None | ||
74 | } | ||
75 | } | ||
76 | |||
77 | pub(crate) fn is_cfg_enabled(&self, cfg_options: &CfgOptions) -> Option<bool> { | ||
78 | cfg_options.is_cfg_enabled(self.as_cfg()?) | ||
79 | } | ||
80 | } | ||