1 //! Renderer for macro invocations.
3 use hir::{Documentation, HasSource};
4 use ide_db::SymbolKind;
5 use syntax::display::macro_label;
8 item::{CompletionItem, CompletionKind, ImportEdit},
12 pub(crate) fn render_macro<'a>(
13 ctx: RenderContext<'a>,
14 import_to_add: Option<ImportEdit>,
16 macro_: hir::MacroDef,
17 ) -> Option<CompletionItem> {
18 let _p = profile::span("render_macro");
19 MacroRender::new(ctx, name, macro_).render(import_to_add)
23 struct MacroRender<'a> {
24 ctx: RenderContext<'a>,
26 macro_: hir::MacroDef,
27 docs: Option<Documentation>,
32 impl<'a> MacroRender<'a> {
33 fn new(ctx: RenderContext<'a>, name: String, macro_: hir::MacroDef) -> MacroRender<'a> {
34 let docs = ctx.docs(macro_);
35 let docs_str = docs.as_ref().map_or("", |s| s.as_str());
36 let (bra, ket) = guess_macro_braces(&name, docs_str);
38 MacroRender { ctx, name, macro_, docs, bra, ket }
41 fn render(&self, import_to_add: Option<ImportEdit>) -> Option<CompletionItem> {
43 CompletionItem::new(CompletionKind::Reference, self.ctx.source_range(), &self.label());
44 item.kind(SymbolKind::Macro)
45 .set_documentation(self.docs.clone())
46 .set_deprecated(self.ctx.is_deprecated(self.macro_))
47 .add_import(import_to_add)
48 .set_detail(self.detail());
50 let needs_bang = self.needs_bang();
51 match self.ctx.snippet_cap() {
52 Some(cap) if needs_bang => {
53 let snippet = self.snippet();
54 let lookup = self.lookup();
55 item.insert_snippet(cap, snippet).lookup_by(lookup);
57 None if needs_bang => {
58 item.insert_text(self.banged_name());
61 cov_mark::hit!(dont_insert_macro_call_parens_unncessary);
62 item.insert_text(&self.name);
69 fn needs_bang(&self) -> bool {
70 self.ctx.completion.use_item_syntax.is_none() && !self.ctx.completion.is_macro_call
73 fn label(&self) -> String {
74 if self.needs_bang() && self.ctx.snippet_cap().is_some() {
75 format!("{}!{}…{}", self.name, self.bra, self.ket)
77 if self.macro_.kind() == hir::MacroKind::Derive {
85 fn snippet(&self) -> String {
86 format!("{}!{}$0{}", self.name, self.bra, self.ket)
89 fn lookup(&self) -> String {
93 fn banged_name(&self) -> String {
94 format!("{}!", self.name)
97 fn detail(&self) -> Option<String> {
98 let ast_node = self.macro_.source(self.ctx.db())?.value.left()?;
99 Some(macro_label(&ast_node))
103 fn guess_macro_braces(macro_name: &str, docs: &str) -> (&'static str, &'static str) {
104 let mut votes = [0, 0, 0];
105 for (idx, s) in docs.match_indices(¯o_name) {
106 let (before, after) = (&docs[..idx], &docs[idx + s.len()..]);
107 // Ensure to match the full word
108 if after.starts_with('!')
109 && !before.ends_with(|c: char| c == '_' || c.is_ascii_alphanumeric())
111 // It may have spaces before the braces like `foo! {}`
112 match after[1..].chars().find(|&c| !c.is_whitespace()) {
113 Some('{') => votes[0] += 1,
114 Some('[') => votes[1] += 1,
115 Some('(') => votes[2] += 1,
121 // Insert a space before `{}`.
122 // We prefer the last one when some votes equal.
123 let (_vote, (bra, ket)) = votes
125 .zip(&[(" {", "}"), ("[", "]"), ("(", ")")])
126 .max_by_key(|&(&vote, _)| vote)
133 use crate::test_utils::check_edit;
136 fn dont_insert_macro_call_parens_unncessary() {
137 cov_mark::check!(dont_insert_macro_call_parens_unncessary);
141 //- /main.rs crate:main deps:foo
143 //- /foo/lib.rs crate:foo
145 macro_rules! frobnicate { () => () }
155 macro_rules! frobnicate { () => () }
156 fn main() { frob$0!(); }
159 macro_rules! frobnicate { () => () }
160 fn main() { frobnicate!(); }
166 fn guesses_macro_braces() {
170 /// Creates a [`Vec`] containing the arguments.
173 /// let v = vec![1, 2, 3];
174 /// assert_eq!(v[0], 1);
175 /// assert_eq!(v[1], 2);
176 /// assert_eq!(v[2], 3);
178 macro_rules! vec { () => {} }
183 /// Creates a [`Vec`] containing the arguments.
186 /// let v = vec![1, 2, 3];
187 /// assert_eq!(v[0], 1);
188 /// assert_eq!(v[1], 2);
189 /// assert_eq!(v[2], 3);
191 macro_rules! vec { () => {} }
193 fn fn main() { vec![$0] }
202 /// Don't call `fooo!()` `fooo!()`, or `_foo![]` `_foo![]`,
203 /// call as `let _=foo! { hello world };`
204 macro_rules! foo { () => {} }
210 /// Don't call `fooo!()` `fooo!()`, or `_foo![]` `_foo![]`,
211 /// call as `let _=foo! { hello world };`
212 macro_rules! foo { () => {} }
213 fn main() { foo! {$0} }