Goto type actions for notable trait hovers

3 files changed, 212 insertions, 79 deletions

diff --git a/crates/ide/src/hover.rs b/crates/ide/src/hover.rs
index d06577d3db2..5ed3b2dbbcf 100644
--- a/crates/ide/src/hover.rs
+++ b/crates/ide/src/hover.rs
@@ -3,10 +3,10 @@ mod render;
 #[cfg(test)]
 mod tests;
 
-use std::iter;
+use std::{iter, ops::Not};
 
 use either::Either;
-use hir::{db::DefDatabase, DescendPreference, HasSource, LangItem, Semantics};
+use hir::{db::DefDatabase, DescendPreference, HasCrate, HasSource, LangItem, Semantics};
 use ide_db::{
     base_db::FileRange,
     defs::{Definition, IdentClass, NameRefClass, OperatorClass},
@@ -64,7 +64,7 @@ pub enum HoverAction {
 }
 
 impl HoverAction {
-    fn goto_type_from_targets(db: &RootDatabase, targets: Vec<hir::ModuleDef>) -> Self {
+    fn goto_type_from_targets(db: &RootDatabase, targets: Vec<hir::ModuleDef>) -> Option<Self> {
         let targets = targets
             .into_iter()
             .filter_map(|it| {
@@ -77,8 +77,8 @@ impl HoverAction {
                     nav: it.try_to_nav(db)?.call_site(),
                 })
             })
-            .collect();
-        HoverAction::GoToType(targets)
+            .collect::<Vec<_>>();
+        targets.is_empty().not().then_some(HoverAction::GoToType(targets))
     }
 }
 
@@ -315,7 +315,7 @@ fn hover_simple(
                     ast::IntNumber(num) => {
                         res.markup = match num.value() {
                             Ok(num) => {
-                                Markup::fenced_block_text(format_args!("{num} (0x{num:X}|0x{num:b})"))
+                                Markup::fenced_block_text(format_args!("{num} (0x{num:X}|0b{num:b})"))
                             },
                             Err(e) => {
                                 Markup::fenced_block_text(format_args!("{e}"))
@@ -365,25 +365,67 @@ fn hover_ranged(
     })
 }
 
+// FIXME: Why is this pub(crate)?
 pub(crate) fn hover_for_definition(
     sema: &Semantics<'_, RootDatabase>,
     file_id: FileId,
-    definition: Definition,
+    def: Definition,
     scope_node: &SyntaxNode,
     config: &HoverConfig,
 ) -> Option<HoverResult> {
-    let famous_defs = match &definition {
+    let famous_defs = match &def {
         Definition::BuiltinType(_) => Some(FamousDefs(sema, sema.scope(scope_node)?.krate())),
         _ => None,
     };
-    render::definition(sema.db, definition, famous_defs.as_ref(), config).map(|markup| {
+
+    let db = sema.db;
+    let def_ty = match def {
+        Definition::Local(it) => Some(it.ty(db)),
+        Definition::GenericParam(hir::GenericParam::ConstParam(it)) => Some(it.ty(db)),
+        Definition::GenericParam(hir::GenericParam::TypeParam(it)) => Some(it.ty(db)),
+        Definition::Field(field) => Some(field.ty(db)),
+        Definition::TupleField(it) => Some(it.ty(db)),
+        Definition::Function(it) => Some(it.ty(db)),
+        Definition::Adt(it) => Some(it.ty(db)),
+        Definition::Const(it) => Some(it.ty(db)),
+        Definition::Static(it) => Some(it.ty(db)),
+        Definition::TypeAlias(it) => Some(it.ty(db)),
+        Definition::BuiltinType(it) => Some(it.ty(db)),
+        _ => None,
+    };
+    let notable_traits = def_ty
+        .map(|ty| {
+            db.notable_traits_in_deps(ty.krate(db).into())
+                .iter()
+                .flat_map(|it| &**it)
+                .filter_map(move |&trait_| {
+                    let trait_ = trait_.into();
+                    ty.impls_trait(db, trait_, &[]).then(|| {
+                        (
+                            trait_,
+                            trait_
+                                .items(db)
+                                .into_iter()
+                                .filter_map(hir::AssocItem::as_type_alias)
+                                .map(|alias| {
+                                    (ty.normalize_trait_assoc_type(db, &[], alias), alias.name(db))
+                                })
+                                .collect::<Vec<_>>(),
+                        )
+                    })
+                })
+                .collect::<Vec<_>>()
+        })
+        .unwrap_or_default();
+
+    render::definition(sema.db, def, famous_defs.as_ref(), &notable_traits, config).map(|markup| {
         HoverResult {
-            markup: render::process_markup(sema.db, definition, &markup, config),
+            markup: render::process_markup(sema.db, def, &markup, config),
             actions: [
-                show_implementations_action(sema.db, definition),
-                show_fn_references_action(sema.db, definition),
-                runnable_action(sema, definition, file_id),
-                goto_type_action_for_def(sema.db, definition),
+                show_implementations_action(sema.db, def),
+                show_fn_references_action(sema.db, def),
+                runnable_action(sema, def, file_id),
+                goto_type_action_for_def(sema.db, def, &notable_traits),
             ]
             .into_iter()
             .flatten()
@@ -446,7 +488,11 @@ fn runnable_action(
     }
 }
 
-fn goto_type_action_for_def(db: &RootDatabase, def: Definition) -> Option<HoverAction> {
+fn goto_type_action_for_def(
+    db: &RootDatabase,
+    def: Definition,
+    notable_traits: &[(hir::Trait, Vec<(Option<hir::Type>, hir::Name)>)],
+) -> Option<HoverAction> {
     let mut targets: Vec<hir::ModuleDef> = Vec::new();
     let mut push_new_def = |item: hir::ModuleDef| {
         if !targets.contains(&item) {
@@ -454,6 +500,13 @@ fn goto_type_action_for_def(db: &RootDatabase, def: Definition) -> Option<HoverA
         }
     };
 
+    for &(trait_, ref assocs) in notable_traits {
+        push_new_def(trait_.into());
+        assocs.iter().filter_map(|(ty, _)| ty.as_ref()).for_each(|ty| {
+            walk_and_push_ty(db, ty, &mut push_new_def);
+        });
+    }
+
     if let Definition::GenericParam(hir::GenericParam::TypeParam(it)) = def {
         let krate = it.module(db).krate();
         let sized_trait =
@@ -469,13 +522,13 @@ fn goto_type_action_for_def(db: &RootDatabase, def: Definition) -> Option<HoverA
             Definition::GenericParam(hir::GenericParam::ConstParam(it)) => it.ty(db),
             Definition::Field(field) => field.ty(db),
             Definition::Function(function) => function.ret_type(db),
-            _ => return None,
+            _ => return HoverAction::goto_type_from_targets(db, targets),
         };
 
         walk_and_push_ty(db, &ty, &mut push_new_def);
     }
 
-    Some(HoverAction::goto_type_from_targets(db, targets))
+    HoverAction::goto_type_from_targets(db, targets)
 }
 
 fn walk_and_push_ty(
diff --git a/crates/ide/src/hover/render.rs b/crates/ide/src/hover/render.rs
index d3a9975b2b2..511137f67c8 100644
--- a/crates/ide/src/hover/render.rs
+++ b/crates/ide/src/hover/render.rs
@@ -3,8 +3,8 @@ use std::{mem, ops::Not};
 
 use either::Either;
 use hir::{
-    db::DefDatabase, Adt, AsAssocItem, AssocItem, CaptureKind, HasCrate, HasSource, HirDisplay,
-    Layout, LayoutError, Semantics, TypeInfo,
+    Adt, AsAssocItem, CaptureKind, HasSource, HirDisplay, Layout, LayoutError, Name, Semantics,
+    Trait, Type, TypeInfo,
 };
 use ide_db::{
     base_db::SourceDatabase,
@@ -117,7 +117,9 @@ pub(super) fn try_expr(
     };
     walk_and_push_ty(sema.db, &inner_ty, &mut push_new_def);
     walk_and_push_ty(sema.db, &body_ty, &mut push_new_def);
-    res.actions.push(HoverAction::goto_type_from_targets(sema.db, targets));
+    if let Some(actions) = HoverAction::goto_type_from_targets(sema.db, targets) {
+        res.actions.push(actions);
+    }
 
     let inner_ty = inner_ty.display(sema.db).to_string();
     let body_ty = body_ty.display(sema.db).to_string();
@@ -195,7 +197,9 @@ pub(super) fn deref_expr(
         )
         .into()
     };
-    res.actions.push(HoverAction::goto_type_from_targets(sema.db, targets));
+    if let Some(actions) = HoverAction::goto_type_from_targets(sema.db, targets) {
+        res.actions.push(actions);
+    }
 
     Some(res)
 }
@@ -302,7 +306,9 @@ pub(super) fn struct_rest_pat(
 
         Markup::fenced_block(&s)
     };
-    res.actions.push(HoverAction::goto_type_from_targets(sema.db, targets));
+    if let Some(actions) = HoverAction::goto_type_from_targets(sema.db, targets) {
+        res.actions.push(actions);
+    }
     res
 }
 
@@ -388,6 +394,7 @@ pub(super) fn definition(
     db: &RootDatabase,
     def: Definition,
     famous_defs: Option<&FamousDefs<'_, '_>>,
+    notable_traits: &[(Trait, Vec<(Option<Type>, Name)>)],
     config: &HoverConfig,
 ) -> Option<Markup> {
     let mod_path = definition_mod_path(db, &def);
@@ -464,58 +471,35 @@ pub(super) fn definition(
         _ => None,
     };
 
-    let def_ty = match def {
-        Definition::Local(it) => Some(it.ty(db)),
-        Definition::GenericParam(hir::GenericParam::ConstParam(it)) => Some(it.ty(db)),
-        Definition::GenericParam(hir::GenericParam::TypeParam(it)) => Some(it.ty(db)),
-        Definition::Field(field) => Some(field.ty(db)),
-        Definition::TupleField(it) => Some(it.ty(db)),
-        Definition::Function(it) => Some(it.ty(db)),
-        Definition::Adt(it) => Some(it.ty(db)),
-        Definition::Const(it) => Some(it.ty(db)),
-        Definition::Static(it) => Some(it.ty(db)),
-        Definition::TypeAlias(it) => Some(it.ty(db)),
-        Definition::BuiltinType(it) => Some(it.ty(db)),
-        _ => None,
-    };
-    let notable_traits = def_ty.and_then(|ty| {
+    let notable_traits = {
         let mut desc = String::new();
         let mut needs_impl_header = true;
-        for &trait_ in db.notable_traits_in_deps(ty.krate(db).into()).iter().flat_map(|it| &**it) {
-            let trait_ = trait_.into();
-            if ty.impls_trait(db, trait_, &[]) {
-                let aliases: Vec<_> = trait_
-                    .items(db)
-                    .into_iter()
-                    .filter_map(AssocItem::as_type_alias)
-                    .map(|alias| (ty.normalize_trait_assoc_type(db, &[], alias), alias.name(db)))
-                    .collect();
-                desc.push_str(if mem::take(&mut needs_impl_header) {
-                    " // notable traits impls: "
-                } else {
-                    ", "
-                });
-                format_to!(desc, "{}", trait_.name(db).display(db),);
-                if !aliases.is_empty() {
-                    desc.push('<');
-                    format_to!(
-                        desc,
-                        "{}",
-                        aliases.into_iter().format_with(", ", |(ty, name), f| {
-                            f(&name.display(db))?;
-                            f(&" = ")?;
-                            match ty {
-                                Some(ty) => f(&ty.display(db)),
-                                None => f(&"?"),
-                            }
-                        })
-                    );
-                    desc.push('>');
-                }
+        for (trait_, assoc_types) in notable_traits {
+            desc.push_str(if mem::take(&mut needs_impl_header) {
+                " // notable traits implemented: "
+            } else {
+                ", "
+            });
+            format_to!(desc, "{}", trait_.name(db).display(db),);
+            if !assoc_types.is_empty() {
+                desc.push('<');
+                format_to!(
+                    desc,
+                    "{}",
+                    assoc_types.into_iter().format_with(", ", |(ty, name), f| {
+                        f(&name.display(db))?;
+                        f(&" = ")?;
+                        match ty {
+                            Some(ty) => f(&ty.display(db)),
+                            None => f(&"?"),
+                        }
+                    })
+                );
+                desc.push('>');
             }
         }
         desc.is_empty().not().then(|| desc)
-    });
+    };
 
     let mut desc = String::new();
     if let Some(notable_traits) = notable_traits {
@@ -569,7 +553,9 @@ fn type_info(
     } else {
         Markup::fenced_block(&original.display(sema.db))
     };
-    res.actions.push(HoverAction::goto_type_from_targets(sema.db, targets));
+    if let Some(actions) = HoverAction::goto_type_from_targets(sema.db, targets) {
+        res.actions.push(actions);
+    }
     Some(res)
 }
 
@@ -629,7 +615,9 @@ fn closure_ty(
     );
 
     let mut res = HoverResult::default();
-    res.actions.push(HoverAction::goto_type_from_targets(sema.db, targets));
+    if let Some(actions) = HoverAction::goto_type_from_targets(sema.db, targets) {
+        res.actions.push(actions);
+    }
     res.markup = markup.into();
     Some(res)
 }
@@ -783,7 +771,9 @@ fn keyword_hints(
                     KeywordHint {
                         description,
                         keyword_mod,
-                        actions: vec![HoverAction::goto_type_from_targets(sema.db, targets)],
+                        actions: HoverAction::goto_type_from_targets(sema.db, targets)
+                            .into_iter()
+                            .collect(),
                     }
                 }
                 _ => KeywordHint {
diff --git a/crates/ide/src/hover/tests.rs b/crates/ide/src/hover/tests.rs
index f8693cd1ea6..09548745f6e 100644
--- a/crates/ide/src/hover/tests.rs
+++ b/crates/ide/src/hover/tests.rs
@@ -6989,7 +6989,7 @@ fn main() {
         expect![[r#"
             *34325236457856836345234*
             ```text
-            34325236457856836345234 (0x744C659178614489D92|0x111010001001100011001011001000101111000011000010100010010001001110110010010)
+            34325236457856836345234 (0x744C659178614489D92|0b111010001001100011001011001000101111000011000010100010010001001110110010010)
             ```
         "#]],
     );
@@ -7002,7 +7002,7 @@ fn main() {
         expect![[r#"
             *134_123424_21*
             ```text
-            13412342421 (0x31F701A95|0x1100011111011100000001101010010101)
+            13412342421 (0x31F701A95|0b1100011111011100000001101010010101)
             ```
         "#]],
     );
@@ -7015,7 +7015,7 @@ fn main() {
         expect![[r#"
             *0x12423423*
             ```text
-            306328611 (0x12423423|0x10010010000100011010000100011)
+            306328611 (0x12423423|0b10010010000100011010000100011)
             ```
         "#]],
     );
@@ -7028,7 +7028,7 @@ fn main() {
         expect![[r#"
             *0b1111_1111*
             ```text
-            255 (0xFF|0x11111111)
+            255 (0xFF|0b11111111)
             ```
         "#]],
     );
@@ -7041,7 +7041,7 @@ fn main() {
         expect![[r#"
             *0o12345*
             ```text
-            5349 (0x14E5|0x1010011100101)
+            5349 (0x14E5|0b1010011100101)
             ```
         "#]],
     );
@@ -7080,7 +7080,7 @@ fn main(notable$0: u32) {}
             *notable*
 
             ```rust
-             // notable traits impls: Notable<Assoc = &str, Assoc2 = char>
+             // notable traits implemented: Notable<Assoc = &str, Assoc2 = char>
              // size = 4, align = 4
             notable: u32
             ```
@@ -7112,10 +7112,100 @@ impl Iterator for S {
             ```
 
             ```rust
-             // notable traits impls: Notable, Future<Output = u32>, Iterator<Item = S>
+             // notable traits implemented: Notable, Future<Output = u32>, Iterator<Item = S>
              // size = 0, align = 1
             struct S
             ```
         "#]],
     );
 }
+
+#[test]
+fn notable_actions() {
+    check_actions(
+        r#"
+//- minicore: future, iterator
+struct S;
+struct S2;
+#[doc(notable_trait)]
+trait Notable {}
+impl Notable for S$0 {}
+impl core::future::Future for S {
+    type Output = u32;
+}
+impl Iterator for S {
+    type Item = S2;
+}
+"#,
+        expect![[r#"
+            [
+                Implementation(
+                    FilePosition {
+                        file_id: FileId(
+                            0,
+                        ),
+                        offset: 7,
+                    },
+                ),
+                GoToType(
+                    [
+                        HoverGotoTypeData {
+                            mod_path: "test::Notable",
+                            nav: NavigationTarget {
+                                file_id: FileId(
+                                    0,
+                                ),
+                                full_range: 21..59,
+                                focus_range: 49..56,
+                                name: "Notable",
+                                kind: Trait,
+                                description: "trait Notable",
+                            },
+                        },
+                        HoverGotoTypeData {
+                            mod_path: "core::future::Future",
+                            nav: NavigationTarget {
+                                file_id: FileId(
+                                    1,
+                                ),
+                                full_range: 6012..6220,
+                                focus_range: 6077..6083,
+                                name: "Future",
+                                kind: Trait,
+                                container_name: "future",
+                                description: "pub trait Future",
+                            },
+                        },
+                        HoverGotoTypeData {
+                            mod_path: "core::iter::traits::iterator::Iterator",
+                            nav: NavigationTarget {
+                                file_id: FileId(
+                                    1,
+                                ),
+                                full_range: 6850..7316,
+                                focus_range: 6894..6902,
+                                name: "Iterator",
+                                kind: Trait,
+                                container_name: "iterator",
+                                description: "pub trait Iterator",
+                            },
+                        },
+                        HoverGotoTypeData {
+                            mod_path: "test::S2",
+                            nav: NavigationTarget {
+                                file_id: FileId(
+                                    0,
+                                ),
+                                full_range: 10..20,
+                                focus_range: 17..19,
+                                name: "S2",
+                                kind: Struct,
+                                description: "struct S2",
+                            },
+                        },
+                    ],
+                ),
+            ]
+        "#]],
+    );
+}