rust-analyzer

diff --git a/crates/hir-def/src/resolver.rs b/crates/hir-def/src/resolver.rs
index 62576100ea..2f9187009e 100644
--- a/crates/hir-def/src/resolver.rs
+++ b/crates/hir-def/src/resolver.rs

@@ -12,6 +12,7 @@ use triomphe::Arc;

use crate::{

body::scope::{ExprScopes, ScopeId},

builtin_type::BuiltinType,

+ data::ExternCrateDeclData,

db::DefDatabase,

generics::{GenericParams, TypeOrConstParamData},

hir::{BindingId, ExprId, LabelId},

@@ -451,6 +452,7 @@ impl Resolver {

def_map[module_id].scope.entries().for_each(|(name, def)| {

res.add_per_ns(name, def);

});

def_map[module_id].scope.legacy_macros().for_each(|(name, macs)| {

macs.iter().for_each(|&mac| {

res.add(name, ScopeDef::ModuleDef(ModuleDefId::MacroId(mac)));

@@ -474,6 +476,23 @@ impl Resolver {

res.map

}

+ pub fn extern_crate_decls_in_scope<'a>(

+ &'a self,

+ db: &'a dyn DefDatabase,

+ ) -> impl Iterator<Item = Name> + 'a {

+ self.module_scope.def_map[self.module_scope.module_id]

+ .scope

+ .extern_crate_decls()

+ .map(|id| ExternCrateDeclData::extern_crate_decl_data_query(db, id).name.clone())

+ }

+ pub fn extern_crates_in_scope<'a>(&'a self) -> impl Iterator<Item = (Name, ModuleId)> + 'a {

+ self.module_scope

+ .def_map

+ .extern_prelude()

+ .map(|(name, module_id)| (name.clone(), module_id.0.into()))

+ }

pub fn traits_in_scope(&self, db: &dyn DefDatabase) -> FxHashSet<TraitId> {

// FIXME(trait_alias): Trait alias brings aliased traits in scope! Note that supertraits of

// aliased traits are NOT brought in scope (unless also aliased).

diff --git a/crates/hir/src/semantics.rs b/crates/hir/src/semantics.rs
index 65ccb8b073..b8d4ecd441 100644
--- a/crates/hir/src/semantics.rs
+++ b/crates/hir/src/semantics.rs

@@ -1722,6 +1722,14 @@ impl SemanticsScope<'_> {

|name, id| cb(name, id.into()),

)

}

+ pub fn extern_crates(&self) -> impl Iterator<Item = (Name, Module)> + '_ {

+ self.resolver.extern_crates_in_scope().map(|(name, id)| (name, Module { id }))

+ }

+ pub fn extern_crate_decls(&self) -> impl Iterator<Item = Name> + '_ {

+ self.resolver.extern_crate_decls_in_scope(self.db.upcast())

+ }

}

#[derive(Debug)]

diff --git a/crates/ide-completion/src/completions.rs b/crates/ide-completion/src/completions.rs
index 7e2ecdbb85..f60ac15016 100644
--- a/crates/ide-completion/src/completions.rs
+++ b/crates/ide-completion/src/completions.rs

@@ -20,6 +20,7 @@ pub(crate) mod r#type;

pub(crate) mod use_;

pub(crate) mod vis;

pub(crate) mod env_vars;

+pub(crate) mod extern_crate;

use std::iter;

@@ -739,6 +740,7 @@ pub(super) fn complete_name_ref(

}

+ NameRefKind::ExternCrate => extern_crate::complete_extern_crate(acc, ctx),

NameRefKind::DotAccess(dot_access) => {

flyimport::import_on_the_fly_dot(acc, ctx, dot_access);

dot::complete_dot(acc, ctx, dot_access);

diff --git a/crates/ide-completion/src/completions/extern_crate.rs b/crates/ide-completion/src/completions/extern_crate.rs
new file mode 100644
index 0000000000..0d0e143f5f
--- /dev/null
+++ b/crates/ide-completion/src/completions/extern_crate.rs

@@ -0,0 +1,71 @@

+//! Completion for extern crates

+use hir::{HasAttrs, Name};

+use ide_db::SymbolKind;

+use crate::{context::CompletionContext, CompletionItem, CompletionItemKind};

+use super::Completions;

+pub(crate) fn complete_extern_crate(acc: &mut Completions, ctx: &CompletionContext<'_>) {

+ let imported_extern_crates: Vec<Name> = ctx.scope.extern_crate_decls().collect();

+ for (name, module) in ctx.scope.extern_crates() {

+ if imported_extern_crates.contains(&name) {

+ continue;

+ }

+ let mut item = CompletionItem::new(

+ CompletionItemKind::SymbolKind(SymbolKind::Module),

+ ctx.source_range(),

+ name.to_smol_str(),

+ );

+ item.set_documentation(module.docs(ctx.db));

+ item.add_to(acc, ctx.db);

+ }

+#[cfg(test)]

+mod test {

+ use crate::tests::completion_list_no_kw;

+ #[test]

+ fn can_complete_extern_crate() {

+ let case = r#"

+//- /lib.rs crate:other_crate_a

+// nothing here

+//- /other_crate_b.rs crate:other_crate_b

+pub mod good_mod{}

+//- /lib.rs crate:crate_c

+// nothing here

+//- /lib.rs crate:lib deps:other_crate_a,other_crate_b,crate_c extern-prelude:other_crate_a

+extern crate oth$0

+mod other_mod {}

+"#;

+ let completion_list = completion_list_no_kw(case);

+ assert_eq!("md other_crate_a\n".to_string(), completion_list);

+ }

+ #[test]

+ fn will_not_complete_existing_import() {

+ let case = r#"

+//- /lib.rs crate:other_crate_a

+// nothing here

+//- /lib.rs crate:crate_c

+// nothing here

+//- /lib.rs crate:other_crate_b

+//

+//- /lib.rs crate:lib deps:other_crate_a,other_crate_b,crate_c extern-prelude:other_crate_a,other_crate_b

+extern crate other_crate_b;

+extern crate oth$0

+mod other_mod {}

+"#;

+ let completion_list = completion_list_no_kw(case);

+ assert_eq!("md other_crate_a\n".to_string(), completion_list);

+ }

diff --git a/crates/ide-completion/src/context.rs b/crates/ide-completion/src/context.rs
index 1fd635ba2e..0da7ba6d00 100644
--- a/crates/ide-completion/src/context.rs
+++ b/crates/ide-completion/src/context.rs

@@ -351,6 +351,7 @@ pub(super) enum NameRefKind {

expr: ast::RecordExpr,

Pattern(PatternContext),

+ ExternCrate,

}

/// The identifier we are currently completing.

diff --git a/crates/ide-completion/src/context/analysis.rs b/crates/ide-completion/src/context/analysis.rs
index c66cb987fe..1e6b2f319a 100644
--- a/crates/ide-completion/src/context/analysis.rs
+++ b/crates/ide-completion/src/context/analysis.rs

@@ -624,6 +624,10 @@ fn classify_name_ref(

});

return Some(make_res(kind));

+ ast::ExternCrate(_) => {

+ let kind = NameRefKind::ExternCrate;

+ return Some(make_res(kind));

+ },

ast::MethodCallExpr(method) => {

let receiver = find_opt_node_in_file(original_file, method.receiver());

let kind = NameRefKind::DotAccess(DotAccess {