Attribute completion is context aware

This commit is contained in:
Lukas Wirth 2021-05-27 23:28:14 +02:00
parent 01bfc5f5c0
commit fc37e2f953
4 changed files with 150 additions and 28 deletions

1
Cargo.lock generated
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@ -647,6 +647,7 @@ dependencies = [
"ide_db",
"itertools",
"log",
"once_cell",
"profile",
"rustc-hash",
"stdx",

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@ -15,6 +15,7 @@ itertools = "0.10.0"
log = "0.4.8"
rustc-hash = "1.1.0"
either = "1.6.1"
once_cell = "1.7"
stdx = { path = "../stdx", version = "0.0.0" }
syntax = { path = "../syntax", version = "0.0.0" }

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@ -4,8 +4,9 @@
//! for built-in attributes.
use itertools::Itertools;
use rustc_hash::FxHashSet;
use syntax::{ast, AstNode, T};
use once_cell::sync::Lazy;
use rustc_hash::{FxHashMap, FxHashSet};
use syntax::{ast, AstNode, SyntaxKind, T};
use crate::{
context::CompletionContext,
@ -20,27 +21,34 @@ pub(crate) fn complete_attribute(acc: &mut Completions, ctx: &CompletionContext)
}
let attribute = ctx.attribute_under_caret.as_ref()?;
match (attribute.path(), attribute.token_tree()) {
(Some(path), Some(token_tree)) => {
let path = path.syntax().text();
if path == "derive" {
complete_derive(acc, ctx, token_tree)
} else if path == "feature" {
complete_lint(acc, ctx, token_tree, FEATURES)
} else if path == "allow" || path == "warn" || path == "deny" || path == "forbid" {
match (attribute.path().and_then(|p| p.as_single_name_ref()), attribute.token_tree()) {
(Some(path), Some(token_tree)) => match path.text().as_str() {
"derive" => complete_derive(acc, ctx, token_tree),
"feature" => complete_lint(acc, ctx, token_tree, FEATURES),
"allow" | "warn" | "deny" | "forbid" => {
complete_lint(acc, ctx, token_tree.clone(), DEFAULT_LINT_COMPLETIONS);
complete_lint(acc, ctx, token_tree, CLIPPY_LINTS);
}
}
(_, Some(_token_tree)) => {}
_ => complete_attribute_start(acc, ctx, attribute),
_ => (),
},
(None, Some(_)) => (),
_ => complete_new_attribute(acc, ctx, attribute),
}
Some(())
}
fn complete_attribute_start(acc: &mut Completions, ctx: &CompletionContext, attribute: &ast::Attr) {
fn complete_new_attribute(acc: &mut Completions, ctx: &CompletionContext, attribute: &ast::Attr) {
let attribute_annotated_item_kind = attribute.syntax().parent().map(|it| it.kind());
let attributes = attribute_annotated_item_kind.and_then(|kind| {
if ast::Expr::can_cast(kind) {
Some(EXPR_ATTRIBUTES)
} else {
KIND_TO_ATTRIBUTES.get(&kind).copied()
}
});
let is_inner = attribute.kind() == ast::AttrKind::Inner;
for attr_completion in ATTRIBUTES.iter().filter(|compl| is_inner || !compl.prefer_inner) {
let add_completion = |attr_completion: &AttrCompletion| {
let mut item = CompletionItem::new(
CompletionKind::Attribute,
ctx.source_range(),
@ -56,9 +64,19 @@ fn complete_attribute_start(acc: &mut Completions, ctx: &CompletionContext, attr
item.insert_snippet(cap, snippet);
}
if attribute.kind() == ast::AttrKind::Inner || !attr_completion.prefer_inner {
if is_inner || !attr_completion.prefer_inner {
acc.add(item.build());
}
};
match attributes {
Some(applicable) => applicable
.iter()
.flat_map(|name| ATTRIBUTES.binary_search_by(|attr| attr.key().cmp(name)).ok())
.flat_map(|idx| ATTRIBUTES.get(idx))
.for_each(add_completion),
None if is_inner => ATTRIBUTES.iter().for_each(add_completion),
None => ATTRIBUTES.iter().filter(|compl| !compl.prefer_inner).for_each(add_completion),
}
}
@ -70,6 +88,10 @@ struct AttrCompletion {
}
impl AttrCompletion {
fn key(&self) -> &'static str {
self.lookup.unwrap_or(self.label)
}
const fn prefer_inner(self) -> AttrCompletion {
AttrCompletion { prefer_inner: true, ..self }
}
@ -83,26 +105,81 @@ const fn attr(
AttrCompletion { label, lookup, snippet, prefer_inner: false }
}
macro_rules! attrs {
[$($($mac:ident!),+;)? $($key:literal),*] => {
&["allow", "cfg", "cfg_attr", "deny", "forbid", "warn", $($($mac!()),+,)? $($key),*] as _
}
}
macro_rules! item_attrs {
() => {
"deprecated"
};
}
static KIND_TO_ATTRIBUTES: Lazy<FxHashMap<SyntaxKind, &[&str]>> = Lazy::new(|| {
std::array::IntoIter::new([
(SyntaxKind::SOURCE_FILE, attrs!(item_attrs!;"crate_name")),
(SyntaxKind::MODULE, attrs!(item_attrs!;)),
(SyntaxKind::ITEM_LIST, attrs!(item_attrs!;)),
(SyntaxKind::MACRO_RULES, attrs!(item_attrs!;)),
(SyntaxKind::MACRO_DEF, attrs!(item_attrs!;)),
(SyntaxKind::EXTERN_CRATE, attrs!(item_attrs!;)),
(SyntaxKind::USE, attrs!(item_attrs!;)),
(SyntaxKind::FN, attrs!(item_attrs!;"cold", "must_use")),
(SyntaxKind::TYPE_ALIAS, attrs!(item_attrs!;)),
(SyntaxKind::STRUCT, attrs!(item_attrs!;"must_use")),
(SyntaxKind::ENUM, attrs!(item_attrs!;"must_use")),
(SyntaxKind::UNION, attrs!(item_attrs!;"must_use")),
(SyntaxKind::CONST, attrs!(item_attrs!;)),
(SyntaxKind::STATIC, attrs!(item_attrs!;)),
(SyntaxKind::TRAIT, attrs!(item_attrs!; "must_use")),
(SyntaxKind::IMPL, attrs!(item_attrs!;"automatically_derived")),
(SyntaxKind::ASSOC_ITEM_LIST, attrs!(item_attrs!;)),
(SyntaxKind::EXTERN_BLOCK, attrs!(item_attrs!;)),
(SyntaxKind::EXTERN_ITEM_LIST, attrs!(item_attrs!;)),
(SyntaxKind::MACRO_CALL, attrs!()),
(SyntaxKind::SELF_PARAM, attrs!()),
(SyntaxKind::PARAM, attrs!()),
(SyntaxKind::RECORD_FIELD, attrs!()),
(SyntaxKind::VARIANT, attrs!()),
(SyntaxKind::TYPE_PARAM, attrs!()),
(SyntaxKind::CONST_PARAM, attrs!()),
(SyntaxKind::LIFETIME_PARAM, attrs!()),
(SyntaxKind::LET_STMT, attrs!()),
(SyntaxKind::EXPR_STMT, attrs!()),
(SyntaxKind::LITERAL, attrs!()),
(SyntaxKind::RECORD_EXPR_FIELD_LIST, attrs!()),
(SyntaxKind::RECORD_EXPR_FIELD, attrs!()),
(SyntaxKind::MATCH_ARM_LIST, attrs!()),
(SyntaxKind::MATCH_ARM, attrs!()),
(SyntaxKind::IDENT_PAT, attrs!()),
(SyntaxKind::RECORD_PAT_FIELD, attrs!()),
])
.collect()
});
const EXPR_ATTRIBUTES: &[&str] = attrs!();
/// https://doc.rust-lang.org/reference/attributes.html#built-in-attributes-index
// Keep these sorted for the binary search!
const ATTRIBUTES: &[AttrCompletion] = &[
attr("allow(…)", Some("allow"), Some("allow(${0:lint})")),
attr("automatically_derived", None, None),
attr("cfg_attr(…)", Some("cfg_attr"), Some("cfg_attr(${1:predicate}, ${0:attr})")),
attr("cfg(…)", Some("cfg"), Some("cfg(${0:predicate})")),
attr("cfg_attr(…)", Some("cfg_attr"), Some("cfg_attr(${1:predicate}, ${0:attr})")),
attr("cold", None, None),
attr(r#"crate_name = """#, Some("crate_name"), Some(r#"crate_name = "${0:crate_name}""#))
.prefer_inner(),
attr("deny(…)", Some("deny"), Some("deny(${0:lint})")),
attr(r#"deprecated"#, Some("deprecated"), Some(r#"deprecated"#)),
attr("derive(…)", Some("derive"), Some(r#"derive(${0:Debug})"#)),
attr(r#"doc = "…""#, Some("doc"), Some(r#"doc = "${0:docs}""#)),
attr(r#"doc(alias = "…")"#, Some("docalias"), Some(r#"doc(alias = "${0:docs}")"#)),
attr(r#"doc(hidden)"#, Some("dochidden"), Some(r#"doc(hidden)"#)),
attr(
r#"export_name = "…""#,
Some("export_name"),
Some(r#"export_name = "${0:exported_symbol_name}""#),
),
attr(r#"doc(alias = "…")"#, Some("docalias"), Some(r#"doc(alias = "${0:docs}")"#)),
attr(r#"doc = "…""#, Some("doc"), Some(r#"doc = "${0:docs}""#)),
attr(r#"doc(hidden)"#, Some("dochidden"), Some(r#"doc(hidden)"#)),
attr("feature(…)", Some("feature"), Some("feature(${0:flag})")).prefer_inner(),
attr("forbid(…)", Some("forbid"), Some("forbid(${0:lint})")),
// FIXME: resolve through macro resolution?
@ -119,8 +196,8 @@ const ATTRIBUTES: &[AttrCompletion] = &[
attr("macro_export", None, None),
attr("macro_use", None, None),
attr(r#"must_use"#, Some("must_use"), Some(r#"must_use"#)),
attr("no_link", None, None).prefer_inner(),
attr("no_implicit_prelude", None, None).prefer_inner(),
attr("no_link", None, None).prefer_inner(),
attr("no_main", None, None).prefer_inner(),
attr("no_mangle", None, None),
attr("no_std", None, None).prefer_inner(),
@ -153,6 +230,22 @@ const ATTRIBUTES: &[AttrCompletion] = &[
.prefer_inner(),
];
#[test]
fn attributes_are_sorted() {
let mut attrs = ATTRIBUTES.iter().map(|attr| attr.key());
let mut prev = attrs.next().unwrap();
attrs.for_each(|next| {
assert!(
prev < next,
r#"Attributes are not sorted, "{}" should come after "{}""#,
prev,
next
);
prev = next;
});
}
fn complete_derive(acc: &mut Completions, ctx: &CompletionContext, derive_input: ast::TokenTree) {
if let Ok(existing_derives) = parse_comma_sep_input(derive_input) {
for derive_completion in DEFAULT_DERIVE_COMPLETIONS
@ -409,6 +502,26 @@ mod tests {
expect.assert_eq(&actual);
}
#[test]
fn complete_attribute_on_struct() {
check(
r#"
#[$0]
struct Test {}
"#,
expect![[r#"
at allow()
at cfg()
at cfg_attr()
at deny()
at forbid()
at warn()
at deprecated
at must_use
"#]],
);
}
#[test]
fn empty_derive_completion() {
check(
@ -468,16 +581,16 @@ struct Test {}
expect![[r#"
at allow()
at automatically_derived
at cfg_attr()
at cfg()
at cfg_attr()
at cold
at deny()
at deprecated
at derive()
at export_name = ""
at doc(alias = "")
at doc = ""
at doc(alias = "")
at doc(hidden)
at export_name = ""
at forbid()
at ignore = ""
at inline
@ -516,17 +629,17 @@ struct Test {}
expect![[r#"
at allow()
at automatically_derived
at cfg_attr()
at cfg()
at cfg_attr()
at cold
at crate_name = ""
at deny()
at deprecated
at derive()
at export_name = ""
at doc(alias = "")
at doc = ""
at doc(alias = "")
at doc(hidden)
at export_name = ""
at feature()
at forbid()
at global_allocator
@ -538,8 +651,8 @@ struct Test {}
at macro_export
at macro_use
at must_use
at no_link
at no_implicit_prelude
at no_link
at no_main
at no_mangle
at no_std

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@ -243,6 +243,13 @@ impl ast::Path {
}
}
pub fn as_single_name_ref(&self) -> Option<ast::NameRef> {
match self.qualifier() {
Some(_) => None,
None => self.segment()?.name_ref(),
}
}
pub fn first_qualifier_or_self(&self) -> ast::Path {
successors(Some(self.clone()), ast::Path::qualifier).last().unwrap()
}