Complete desugared and resugared async fn in trait impls

This commit is contained in:
Lukas Wirth 2024-09-01 11:04:45 +02:00
parent 18feb726be
commit eb64cc8c35
5 changed files with 267 additions and 87 deletions

View file

@ -2207,51 +2207,33 @@ impl Function {
db.function_data(self.id).is_async()
}
/// Whether this function is a `fn` that returns `impl Future`.
pub fn is_desugar_async(self, db: &dyn HirDatabase) -> bool {
if self.is_async(db) || self.is_const(db) {
return false;
pub fn returns_impl_future(self, db: &dyn HirDatabase) -> bool {
if self.is_async(db) {
return true;
}
let Some(impl_traits) = self.ret_type(db).as_impl_traits(db) else { return false };
let Some(future_trait_id) =
db.lang_item(self.ty(db).env.krate, LangItem::Future).and_then(|t| t.as_trait())
else {
return false;
};
let Some(size_trait_id) =
let Some(sized_trait_id) =
db.lang_item(self.ty(db).env.krate, LangItem::Sized).and_then(|t| t.as_trait())
else {
return false;
};
let Some(sync_trait_id) =
db.lang_item(self.ty(db).env.krate, LangItem::Sync).and_then(|t| t.as_trait())
else {
return false;
};
// TODO: There's no `LangItem::Send`. How do we get the id of `Send` trait?
// let Some(send_trait_id) = db.lang_item(self.ty(db).env.krate, LangItem::Send).and_then(|t| t.as_trait()) else {
// eprint!("no future_trait_id\n");
// return false
// };
let allowed_to_leaked_types = vec![size_trait_id, sync_trait_id];
let mut has_impl_future = false;
let mut has_types_not_allow_to_leaked = false;
for impl_trait in impl_traits {
if impl_trait.id == future_trait_id {
has_impl_future = true;
} else if !allowed_to_leaked_types.contains(&impl_trait.id) {
has_types_not_allow_to_leaked = true;
}
}
has_impl_future && !has_types_not_allow_to_leaked
impl_traits
.filter(|t| {
let fut = t.id == future_trait_id;
has_impl_future |= fut;
!fut && t.id != sized_trait_id
})
// all traits but the future trait must be auto traits
.all(|t| t.is_auto(db))
&& has_impl_future
}
/// Does this function have `#[test]` attribute?

View file

@ -31,14 +31,14 @@
//! }
//! ```
use hir::HasAttrs;
use hir::{HasAttrs, Name};
use ide_db::{
documentation::HasDocs, path_transform::PathTransform,
syntax_helpers::insert_whitespace_into_node, traits::get_missing_assoc_items, SymbolKind,
};
use syntax::{
ast::{self, edit_in_place::AttrsOwnerEdit, HasTypeBounds},
format_smolstr, AstNode, SmolStr, SyntaxElement, SyntaxKind, TextRange, ToSmolStr, T,
ast::{self, edit_in_place::AttrsOwnerEdit, make, HasGenericArgs, HasTypeBounds},
format_smolstr, ted, AstNode, SmolStr, SyntaxElement, SyntaxKind, TextRange, ToSmolStr, T,
};
use text_edit::TextEdit;
@ -178,12 +178,36 @@ fn add_function_impl(
func: hir::Function,
impl_def: hir::Impl,
) {
let fn_name = func.name(ctx.db);
let fn_name = &func.name(ctx.db);
let sugar: &[_] = if func.is_async(ctx.db) {
&[AsyncSugaring::Async, AsyncSugaring::Desugar]
} else if func.returns_impl_future(ctx.db) {
&[AsyncSugaring::Plain, AsyncSugaring::Resugar]
} else {
&[AsyncSugaring::Plain]
};
for &sugaring in sugar {
add_function_impl_(acc, ctx, replacement_range, func, impl_def, fn_name, sugaring);
}
}
let is_async = func.is_async(ctx.db);
fn add_function_impl_(
acc: &mut Completions,
ctx: &CompletionContext<'_>,
replacement_range: TextRange,
func: hir::Function,
impl_def: hir::Impl,
fn_name: &Name,
async_sugaring: AsyncSugaring,
) {
let async_ = if let AsyncSugaring::Async | AsyncSugaring::Resugar = async_sugaring {
"async "
} else {
""
};
let label = format_smolstr!(
"{}fn {}({})",
if is_async { "async " } else { "" },
async_,
fn_name.display(ctx.db, ctx.edition),
if func.assoc_fn_params(ctx.db).is_empty() { "" } else { ".." }
);
@ -195,22 +219,14 @@ fn add_function_impl(
});
let mut item = CompletionItem::new(completion_kind, replacement_range, label, ctx.edition);
item.lookup_by(format!(
"{}fn {}",
if is_async { "async " } else { "" },
fn_name.display(ctx.db, ctx.edition)
))
.set_documentation(func.docs(ctx.db))
.set_relevance(CompletionRelevance { is_item_from_trait: true, ..Default::default() });
item.lookup_by(format!("{}fn {}", async_, fn_name.display(ctx.db, ctx.edition)))
.set_documentation(func.docs(ctx.db))
.set_relevance(CompletionRelevance { is_item_from_trait: true, ..Default::default() });
if let Some(source) = ctx.sema.source(func) {
let assoc_item = ast::AssocItem::Fn(source.value);
if let Some(transformed_item) = get_transformed_assoc_item(ctx, assoc_item, impl_def) {
let transformed_fn = match transformed_item {
ast::AssocItem::Fn(func) => func,
_ => unreachable!(),
};
// TODO: need `function_decl` that unwraps future in the return type
if let Some(transformed_fn) =
get_transformed_fn(ctx, source.value, impl_def, async_sugaring)
{
let function_decl = function_declaration(&transformed_fn, source.file_id.is_macro());
match ctx.config.snippet_cap {
Some(cap) => {
@ -225,42 +241,14 @@ fn add_function_impl(
item.add_to(acc, ctx.db);
}
}
}
eprint!("is_desugar_async: {}", func.is_desugar_async(ctx.db));
if func.is_desugar_async(ctx.db) {
let label = format_smolstr!(
"async fn {}({})",
fn_name.display(ctx.db),
if func.assoc_fn_params(ctx.db).is_empty() { "" } else { ".." }
);
let mut item = CompletionItem::new(completion_kind, replacement_range, label);
item.lookup_by(format!("async fn {}", fn_name.display(ctx.db)))
.set_documentation(func.docs(ctx.db))
.set_relevance(CompletionRelevance { is_item_from_trait: true, ..Default::default() });
if let Some(source) = ctx.sema.source(func) {
let assoc_item = ast::AssocItem::Fn(source.value);
if let Some(transformed_item) = get_transformed_assoc_item(ctx, assoc_item, impl_def) {
let transformed_fn = match transformed_item {
ast::AssocItem::Fn(func) => func,
_ => unreachable!(),
};
let function_decl =
function_declaration(&transformed_fn, source.file_id.is_macro());
match ctx.config.snippet_cap {
Some(cap) => {
let snippet = format!("{function_decl} {{\n $0\n}}");
item.snippet_edit(cap, TextEdit::replace(replacement_range, snippet));
}
None => {
let header = format!("{function_decl} {{");
item.text_edit(TextEdit::replace(replacement_range, header));
}
};
item.add_to(acc, ctx.db);
}
}
}
#[derive(Copy, Clone)]
enum AsyncSugaring {
Desugar,
Resugar,
Async,
Plain,
}
/// Transform a relevant associated item to inline generics from the impl, remove attrs and docs, etc.
@ -287,6 +275,82 @@ fn get_transformed_assoc_item(
Some(assoc_item)
}
/// Transform a relevant associated item to inline generics from the impl, remove attrs and docs, etc.
fn get_transformed_fn(
ctx: &CompletionContext<'_>,
fn_: ast::Fn,
impl_def: hir::Impl,
async_: AsyncSugaring,
) -> Option<ast::Fn> {
let trait_ = impl_def.trait_(ctx.db)?;
let source_scope = &ctx.sema.scope(fn_.syntax())?;
let target_scope = &ctx.sema.scope(ctx.sema.source(impl_def)?.syntax().value)?;
let transform = PathTransform::trait_impl(
target_scope,
source_scope,
trait_,
ctx.sema.source(impl_def)?.value,
);
let fn_ = fn_.clone_for_update();
// FIXME: Paths in nested macros are not handled well. See
// `macro_generated_assoc_item2` test.
transform.apply(fn_.syntax());
fn_.remove_attrs_and_docs();
match async_ {
AsyncSugaring::Desugar => {
match fn_.ret_type() {
Some(ret_ty) => {
let ty = ret_ty.ty()?;
ted::replace(
ty.syntax(),
make::ty(&format!("impl Future<Output = {ty}>"))
.syntax()
.clone_for_update(),
);
}
None => ted::append_child(
fn_.param_list()?.syntax(),
make::ret_type(make::ty("impl Future<Output = ()>"))
.syntax()
.clone_for_update(),
),
}
fn_.async_token().unwrap().detach();
}
AsyncSugaring::Resugar => {
let ty = fn_.ret_type()?.ty()?;
match &ty {
// best effort guessing here
ast::Type::ImplTraitType(t) => {
let output = t.type_bound_list()?.bounds().find_map(|b| match b.ty()? {
ast::Type::PathType(p) => {
let p = p.path()?.segment()?;
if p.name_ref()?.text() != "Future" {
return None;
}
match p.generic_arg_list()?.generic_args().next()? {
ast::GenericArg::AssocTypeArg(a)
if a.name_ref()?.text() == "Output" =>
{
a.ty()
}
_ => None,
}
}
_ => None,
})?;
ted::replace(ty.syntax(), output.syntax());
}
_ => (),
}
ted::prepend_child(fn_.syntax(), make::token(T![async]));
}
AsyncSugaring::Async | AsyncSugaring::Plain => (),
}
Some(fn_)
}
fn add_type_alias_impl(
acc: &mut Completions,
ctx: &CompletionContext<'_>,
@ -1437,6 +1501,134 @@ trait Tr {
impl Tr for () {
type Item = $0;
}
"#,
);
}
#[test]
fn impl_fut() {
check_edit(
"fn foo",
r#"
//- minicore: future, send, sized
use core::future::Future;
trait DesugaredAsyncTrait {
fn foo(&self) -> impl Future<Output = usize> + Send;
}
impl DesugaredAsyncTrait for () {
$0
}
"#,
r#"
use core::future::Future;
trait DesugaredAsyncTrait {
fn foo(&self) -> impl Future<Output = usize> + Send;
}
impl DesugaredAsyncTrait for () {
fn foo(&self) -> impl Future<Output = usize> + Send {
$0
}
}
"#,
);
}
#[test]
fn impl_fut_resugared() {
check_edit(
"async fn foo",
r#"
//- minicore: future, send, sized
use core::future::Future;
trait DesugaredAsyncTrait {
fn foo(&self) -> impl Future<Output = usize> + Send;
}
impl DesugaredAsyncTrait for () {
$0
}
"#,
r#"
use core::future::Future;
trait DesugaredAsyncTrait {
fn foo(&self) -> impl Future<Output = usize> + Send;
}
impl DesugaredAsyncTrait for () {
async fn foo(&self) -> usize {
$0
}
}
"#,
);
}
#[test]
fn async_desugared() {
check_edit(
"fn foo",
r#"
//- minicore: future, send, sized
use core::future::Future;
trait DesugaredAsyncTrait {
async fn foo(&self) -> usize;
}
impl DesugaredAsyncTrait for () {
$0
}
"#,
r#"
use core::future::Future;
trait DesugaredAsyncTrait {
async fn foo(&self) -> usize;
}
impl DesugaredAsyncTrait for () {
fn foo(&self) -> impl Future<Output = usize> {
$0
}
}
"#,
);
}
#[test]
fn async_() {
check_edit(
"async fn foo",
r#"
//- minicore: future, send, sized
use core::future::Future;
trait DesugaredAsyncTrait {
async fn foo(&self) -> usize;
}
impl DesugaredAsyncTrait for () {
$0
}
"#,
r#"
use core::future::Future;
trait DesugaredAsyncTrait {
async fn foo(&self) -> usize;
}
impl DesugaredAsyncTrait for () {
async fn foo(&self) -> usize {
$0
}
}
"#,
);
}

View file

@ -313,6 +313,7 @@ impl Test for () {
ct const CONST1: () =
fn async fn function2()
fn fn function1()
fn fn function2()
ma makro!() macro_rules! makro
md module
ta type Type1 =

View file

@ -1162,7 +1162,7 @@ pub mod tokens {
pub(super) static SOURCE_FILE: LazyLock<Parse<SourceFile>> = LazyLock::new(|| {
SourceFile::parse(
"const C: <()>::Item = ( true && true , true || true , 1 != 1, 2 == 2, 3 < 3, 4 <= 4, 5 > 5, 6 >= 6, !true, *p, &p , &mut p, { let _ @ [] })\n;\n\nimpl A for B where: {}", Edition::CURRENT,
"const C: <()>::Item = ( true && true , true || true , 1 != 1, 2 == 2, 3 < 3, 4 <= 4, 5 > 5, 6 >= 6, !true, *p, &p , &mut p, async { let _ @ [] })\n;\n\nimpl A for B where: {}", Edition::CURRENT,
)
});

View file

@ -147,6 +147,11 @@ pub fn append_child_raw(node: &(impl Into<SyntaxNode> + Clone), child: impl Elem
insert_raw(position, child);
}
pub fn prepend_child(node: &(impl Into<SyntaxNode> + Clone), child: impl Element) {
let position = Position::first_child_of(node);
insert(position, child);
}
fn ws_before(position: &Position, new: &SyntaxElement) -> Option<SyntaxToken> {
let prev = match &position.repr {
PositionRepr::FirstChild(_) => return None,