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authorAleksey Kladov <[email protected]>2019-01-08 19:33:36 +0000
committerAleksey Kladov <[email protected]>2019-01-08 19:33:36 +0000
commit5b573deb20b15451788dd2861e9fc6e69ed0472e (patch)
tree0b9438789c69af28fd1d91ca3c25c268ef103bac /crates/ra_ide_api/src/completion/completion_context.rs
parent6bca91af532d79abbced5b151cb4188ff8625c04 (diff)
fix usages after rename
Diffstat (limited to 'crates/ra_ide_api/src/completion/completion_context.rs')
-rw-r--r--crates/ra_ide_api/src/completion/completion_context.rs205
1 files changed, 205 insertions, 0 deletions
diff --git a/crates/ra_ide_api/src/completion/completion_context.rs b/crates/ra_ide_api/src/completion/completion_context.rs
new file mode 100644
index 000000000..01786bb69
--- /dev/null
+++ b/crates/ra_ide_api/src/completion/completion_context.rs
@@ -0,0 +1,205 @@
1use ra_text_edit::AtomTextEdit;
2use ra_syntax::{
3 AstNode, SyntaxNode, SourceFile, TextUnit, TextRange,
4 ast,
5 algo::{find_leaf_at_offset, find_covering_node, find_node_at_offset},
6 SyntaxKind::*,
7};
8use hir::source_binder;
9
10use crate::{db, FilePosition, Cancelable};
11
12/// `CompletionContext` is created early during completion to figure out, where
13/// exactly is the cursor, syntax-wise.
14#[derive(Debug)]
15pub(super) struct CompletionContext<'a> {
16 pub(super) db: &'a db::RootDatabase,
17 pub(super) offset: TextUnit,
18 pub(super) leaf: &'a SyntaxNode,
19 pub(super) module: Option<hir::Module>,
20 pub(super) function: Option<hir::Function>,
21 pub(super) function_syntax: Option<&'a ast::FnDef>,
22 pub(super) use_item_syntax: Option<&'a ast::UseItem>,
23 pub(super) is_param: bool,
24 /// A single-indent path, like `foo`.
25 pub(super) is_trivial_path: bool,
26 /// If not a trivial, path, the prefix (qualifier).
27 pub(super) path_prefix: Option<hir::Path>,
28 pub(super) after_if: bool,
29 /// `true` if we are a statement or a last expr in the block.
30 pub(super) can_be_stmt: bool,
31 /// Something is typed at the "top" level, in module or impl/trait.
32 pub(super) is_new_item: bool,
33 /// The receiver if this is a field or method access, i.e. writing something.<|>
34 pub(super) dot_receiver: Option<&'a ast::Expr>,
35 /// If this is a method call in particular, i.e. the () are already there.
36 pub(super) is_method_call: bool,
37}
38
39impl<'a> CompletionContext<'a> {
40 pub(super) fn new(
41 db: &'a db::RootDatabase,
42 original_file: &'a SourceFile,
43 position: FilePosition,
44 ) -> Cancelable<Option<CompletionContext<'a>>> {
45 let module = source_binder::module_from_position(db, position)?;
46 let leaf =
47 ctry!(find_leaf_at_offset(original_file.syntax(), position.offset).left_biased());
48 let mut ctx = CompletionContext {
49 db,
50 leaf,
51 offset: position.offset,
52 module,
53 function: None,
54 function_syntax: None,
55 use_item_syntax: None,
56 is_param: false,
57 is_trivial_path: false,
58 path_prefix: None,
59 after_if: false,
60 can_be_stmt: false,
61 is_new_item: false,
62 dot_receiver: None,
63 is_method_call: false,
64 };
65 ctx.fill(original_file, position.offset);
66 Ok(Some(ctx))
67 }
68
69 fn fill(&mut self, original_file: &'a SourceFile, offset: TextUnit) {
70 // Insert a fake ident to get a valid parse tree. We will use this file
71 // to determine context, though the original_file will be used for
72 // actual completion.
73 let file = {
74 let edit = AtomTextEdit::insert(offset, "intellijRulezz".to_string());
75 original_file.reparse(&edit)
76 };
77
78 // First, let's try to complete a reference to some declaration.
79 if let Some(name_ref) = find_node_at_offset::<ast::NameRef>(file.syntax(), offset) {
80 // Special case, `trait T { fn foo(i_am_a_name_ref) {} }`.
81 // See RFC#1685.
82 if is_node::<ast::Param>(name_ref.syntax()) {
83 self.is_param = true;
84 return;
85 }
86 self.classify_name_ref(original_file, name_ref);
87 }
88
89 // Otherwise, see if this is a declaration. We can use heuristics to
90 // suggest declaration names, see `CompletionKind::Magic`.
91 if let Some(name) = find_node_at_offset::<ast::Name>(file.syntax(), offset) {
92 if is_node::<ast::Param>(name.syntax()) {
93 self.is_param = true;
94 return;
95 }
96 }
97 }
98 fn classify_name_ref(&mut self, original_file: &'a SourceFile, name_ref: &ast::NameRef) {
99 let name_range = name_ref.syntax().range();
100 let top_node = name_ref
101 .syntax()
102 .ancestors()
103 .take_while(|it| it.range() == name_range)
104 .last()
105 .unwrap();
106
107 match top_node.parent().map(|it| it.kind()) {
108 Some(SOURCE_FILE) | Some(ITEM_LIST) => {
109 self.is_new_item = true;
110 return;
111 }
112 _ => (),
113 }
114
115 self.use_item_syntax = self.leaf.ancestors().find_map(ast::UseItem::cast);
116
117 self.function_syntax = self
118 .leaf
119 .ancestors()
120 .take_while(|it| it.kind() != SOURCE_FILE && it.kind() != MODULE)
121 .find_map(ast::FnDef::cast);
122 match (&self.module, self.function_syntax) {
123 (Some(module), Some(fn_def)) => {
124 let function = source_binder::function_from_module(self.db, module, fn_def);
125 self.function = Some(function);
126 }
127 _ => (),
128 }
129
130 let parent = match name_ref.syntax().parent() {
131 Some(it) => it,
132 None => return,
133 };
134 if let Some(segment) = ast::PathSegment::cast(parent) {
135 let path = segment.parent_path();
136 if let Some(mut path) = hir::Path::from_ast(path) {
137 if !path.is_ident() {
138 path.segments.pop().unwrap();
139 self.path_prefix = Some(path);
140 return;
141 }
142 }
143 if path.qualifier().is_none() {
144 self.is_trivial_path = true;
145
146 // Find either enclosing expr statement (thing with `;`) or a
147 // block. If block, check that we are the last expr.
148 self.can_be_stmt = name_ref
149 .syntax()
150 .ancestors()
151 .find_map(|node| {
152 if let Some(stmt) = ast::ExprStmt::cast(node) {
153 return Some(stmt.syntax().range() == name_ref.syntax().range());
154 }
155 if let Some(block) = ast::Block::cast(node) {
156 return Some(
157 block.expr().map(|e| e.syntax().range())
158 == Some(name_ref.syntax().range()),
159 );
160 }
161 None
162 })
163 .unwrap_or(false);
164
165 if let Some(off) = name_ref.syntax().range().start().checked_sub(2.into()) {
166 if let Some(if_expr) =
167 find_node_at_offset::<ast::IfExpr>(original_file.syntax(), off)
168 {
169 if if_expr.syntax().range().end() < name_ref.syntax().range().start() {
170 self.after_if = true;
171 }
172 }
173 }
174 }
175 }
176 if let Some(field_expr) = ast::FieldExpr::cast(parent) {
177 // The receiver comes before the point of insertion of the fake
178 // ident, so it should have the same range in the non-modified file
179 self.dot_receiver = field_expr
180 .expr()
181 .map(|e| e.syntax().range())
182 .and_then(|r| find_node_with_range(original_file.syntax(), r));
183 }
184 if let Some(method_call_expr) = ast::MethodCallExpr::cast(parent) {
185 // As above
186 self.dot_receiver = method_call_expr
187 .expr()
188 .map(|e| e.syntax().range())
189 .and_then(|r| find_node_with_range(original_file.syntax(), r));
190 self.is_method_call = true;
191 }
192 }
193}
194
195fn find_node_with_range<N: AstNode>(syntax: &SyntaxNode, range: TextRange) -> Option<&N> {
196 let node = find_covering_node(syntax, range);
197 node.ancestors().find_map(N::cast)
198}
199
200fn is_node<N: AstNode>(node: &SyntaxNode) -> bool {
201 match node.ancestors().filter_map(N::cast).next() {
202 None => false,
203 Some(n) => n.syntax().range() == node.range(),
204 }
205}