Merge #5917

5917: Add a command to open docs for the symbol under the cursor r=matklad a=zacps

#### Todo

- [ ] Decide if there should be a default keybind or context menu entry
- [x] Figure out how to get the documentation path for methods and other non-top-level defs
- [x] Design the protocol extension. In future we'll probably want parameters for local/remote documentation URLs, so that should maybe be done in this PR?
- [x] Code organisation
- [x] Tests


Co-authored-by: Zac Pullar-Strecker <zacmps@gmail.com>

Author: bors[bot]

crates/hir/src/code_model.rs

@@ -186,6 +186,16 @@ impl_from!(
     for ModuleDef
 );
 
+impl From<VariantDef> for ModuleDef {
+    fn from(var: VariantDef) -> Self {
+        match var {
+            VariantDef::Struct(t) => Adt::from(t).into(),
+            VariantDef::Union(t) => Adt::from(t).into(),
+            VariantDef::EnumVariant(t) => t.into(),
+        }
+    }
+}
+
 impl ModuleDef {
     pub fn module(self, db: &dyn HirDatabase) -> Option<Module> {
         match self {
@@ -752,6 +762,13 @@ impl Function {
     pub fn diagnostics(self, db: &dyn HirDatabase, sink: &mut DiagnosticSink) {
         hir_ty::diagnostics::validate_body(db, self.id.into(), sink)
     }
+
+    /// Whether this function declaration has a definition.
+    ///
+    /// This is false in the case of required (not provided) trait methods.
+    pub fn has_body(self, db: &dyn HirDatabase) -> bool {
+        db.function_data(self.id).has_body
+    }
 }
 
 // Note: logically, this belongs to `hir_ty`, but we are not using it there yet.

crates/hir_def/src/data.rs

@@ -25,6 +25,7 @@ pub struct FunctionData {
     /// True if the first param is `self`. This is relevant to decide whether this
     /// can be called as a method.
     pub has_self_param: bool,
+    pub has_body: bool,
     pub is_unsafe: bool,
     pub is_varargs: bool,
     pub visibility: RawVisibility,
@@ -42,6 +43,7 @@ impl FunctionData {
             ret_type: func.ret_type.clone(),
             attrs: item_tree.attrs(ModItem::from(loc.id.value).into()).clone(),
             has_self_param: func.has_self_param,
+            has_body: func.has_body,
             is_unsafe: func.is_unsafe,
             is_varargs: func.is_varargs,
             visibility: item_tree[func.visibility].clone(),

crates/hir_def/src/item_tree.rs

@@ -505,6 +505,7 @@ pub struct Function {
     pub visibility: RawVisibilityId,
     pub generic_params: GenericParamsId,
     pub has_self_param: bool,
+    pub has_body: bool,
     pub is_unsafe: bool,
     pub params: Box<[TypeRef]>,
     pub is_varargs: bool,

crates/hir_def/src/item_tree/lower.rs

@@ -330,12 +330,15 @@ impl Ctx {
             ret_type
         };
 
+        let has_body = func.body().is_some();
+
         let ast_id = self.source_ast_id_map.ast_id(func);
         let mut res = Function {
             name,
             visibility,
             generic_params: GenericParamsId::EMPTY,
             has_self_param,
+            has_body,
             is_unsafe: func.unsafe_token().is_some(),
             params: params.into_boxed_slice(),
             is_varargs,

crates/hir_def/src/item_tree/tests.rs

@@ -240,9 +240,9 @@ fn smoke() {
             > #[Attrs { entries: Some([Attr { path: ModPath { kind: Plain, segments: [Name(Text("assoc_const"))] }, input: None }]) }]
             > Const { name: Some(Name(Text("CONST"))), visibility: RawVisibilityId("pub(self)"), type_ref: Path(Path { type_anchor: None, mod_path: ModPath { kind: Plain, segments: [Name(Text("u8"))] }, generic_args: [None] }), ast_id: FileAstId::<syntax::ast::generated::nodes::Const>(9) }
             > #[Attrs { entries: Some([Attr { path: ModPath { kind: Plain, segments: [Name(Text("assoc_method"))] }, input: None }]) }]
-            > Function { name: Name(Text("method")), visibility: RawVisibilityId("pub(self)"), generic_params: GenericParamsId(4294967295), has_self_param: true, is_unsafe: false, params: [Reference(Path(Path { type_anchor: None, mod_path: ModPath { kind: Plain, segments: [Name(Text("Self"))] }, generic_args: [None] }), Shared)], is_varargs: false, ret_type: Tuple([]), ast_id: FileAstId::<syntax::ast::generated::nodes::Fn>(10) }
+            > Function { name: Name(Text("method")), visibility: RawVisibilityId("pub(self)"), generic_params: GenericParamsId(4294967295), has_self_param: true, has_body: false, is_unsafe: false, params: [Reference(Path(Path { type_anchor: None, mod_path: ModPath { kind: Plain, segments: [Name(Text("Self"))] }, generic_args: [None] }), Shared)], is_varargs: false, ret_type: Tuple([]), ast_id: FileAstId::<syntax::ast::generated::nodes::Fn>(10) }
             > #[Attrs { entries: Some([Attr { path: ModPath { kind: Plain, segments: [Name(Text("assoc_dfl_method"))] }, input: None }]) }]
-            > Function { name: Name(Text("dfl_method")), visibility: RawVisibilityId("pub(self)"), generic_params: GenericParamsId(4294967295), has_self_param: true, is_unsafe: false, params: [Reference(Path(Path { type_anchor: None, mod_path: ModPath { kind: Plain, segments: [Name(Text("Self"))] }, generic_args: [None] }), Mut)], is_varargs: false, ret_type: Tuple([]), ast_id: FileAstId::<syntax::ast::generated::nodes::Fn>(11) }
+            > Function { name: Name(Text("dfl_method")), visibility: RawVisibilityId("pub(self)"), generic_params: GenericParamsId(4294967295), has_self_param: true, has_body: true, is_unsafe: false, params: [Reference(Path(Path { type_anchor: None, mod_path: ModPath { kind: Plain, segments: [Name(Text("Self"))] }, generic_args: [None] }), Mut)], is_varargs: false, ret_type: Tuple([]), ast_id: FileAstId::<syntax::ast::generated::nodes::Fn>(11) }
             #[Attrs { entries: Some([Attr { path: ModPath { kind: Plain, segments: [Name(Text("struct0"))] }, input: None }]) }]
             Struct { name: Name(Text("Struct0")), visibility: RawVisibilityId("pub(self)"), generic_params: GenericParamsId(1), fields: Unit, ast_id: FileAstId::<syntax::ast::generated::nodes::Struct>(3), kind: Unit }
             #[Attrs { entries: Some([Attr { path: ModPath { kind: Plain, segments: [Name(Text("struct1"))] }, input: None }]) }]
@@ -275,12 +275,12 @@ fn simple_inner_items() {
 
             top-level items:
             Impl { generic_params: GenericParamsId(0), target_trait: Some(Path(Path { type_anchor: None, mod_path: ModPath { kind: Plain, segments: [Name(Text("D"))] }, generic_args: [None] })), target_type: Path(Path { type_anchor: None, mod_path: ModPath { kind: Plain, segments: [Name(Text("Response"))] }, generic_args: [Some(GenericArgs { args: [Type(Path(Path { type_anchor: None, mod_path: ModPath { kind: Plain, segments: [Name(Text("T"))] }, generic_args: [None] }))], has_self_type: false, bindings: [] })] }), is_negative: false, items: [Function(Idx::<Function>(1))], ast_id: FileAstId::<syntax::ast::generated::nodes::Impl>(0) }
-            > Function { name: Name(Text("foo")), visibility: RawVisibilityId("pub(self)"), generic_params: GenericParamsId(4294967295), has_self_param: false, is_unsafe: false, params: [], is_varargs: false, ret_type: Tuple([]), ast_id: FileAstId::<syntax::ast::generated::nodes::Fn>(1) }
+            > Function { name: Name(Text("foo")), visibility: RawVisibilityId("pub(self)"), generic_params: GenericParamsId(4294967295), has_self_param: false, has_body: true, is_unsafe: false, params: [], is_varargs: false, ret_type: Tuple([]), ast_id: FileAstId::<syntax::ast::generated::nodes::Fn>(1) }
 
             inner items:
 
             for AST FileAstId::<syntax::ast::generated::nodes::Item>(2):
-            Function { name: Name(Text("end")), visibility: RawVisibilityId("pub(self)"), generic_params: GenericParamsId(1), has_self_param: false, is_unsafe: false, params: [], is_varargs: false, ret_type: Tuple([]), ast_id: FileAstId::<syntax::ast::generated::nodes::Fn>(2) }
+            Function { name: Name(Text("end")), visibility: RawVisibilityId("pub(self)"), generic_params: GenericParamsId(1), has_self_param: false, has_body: true, is_unsafe: false, params: [], is_varargs: false, ret_type: Tuple([]), ast_id: FileAstId::<syntax::ast::generated::nodes::Fn>(2) }
 
         "#]],
     );
@@ -303,9 +303,9 @@ fn extern_attrs() {
 
             top-level items:
             #[Attrs { entries: Some([Attr { path: ModPath { kind: Plain, segments: [Name(Text("attr_a"))] }, input: None }, Attr { path: ModPath { kind: Plain, segments: [Name(Text("block_attr"))] }, input: None }]) }]
-            Function { name: Name(Text("a")), visibility: RawVisibilityId("pub(self)"), generic_params: GenericParamsId(4294967295), has_self_param: false, is_unsafe: true, params: [], is_varargs: false, ret_type: Tuple([]), ast_id: FileAstId::<syntax::ast::generated::nodes::Fn>(1) }
+            Function { name: Name(Text("a")), visibility: RawVisibilityId("pub(self)"), generic_params: GenericParamsId(4294967295), has_self_param: false, has_body: true, is_unsafe: true, params: [], is_varargs: false, ret_type: Tuple([]), ast_id: FileAstId::<syntax::ast::generated::nodes::Fn>(1) }
             #[Attrs { entries: Some([Attr { path: ModPath { kind: Plain, segments: [Name(Text("attr_b"))] }, input: None }, Attr { path: ModPath { kind: Plain, segments: [Name(Text("block_attr"))] }, input: None }]) }]
-            Function { name: Name(Text("b")), visibility: RawVisibilityId("pub(self)"), generic_params: GenericParamsId(4294967295), has_self_param: false, is_unsafe: true, params: [], is_varargs: false, ret_type: Tuple([]), ast_id: FileAstId::<syntax::ast::generated::nodes::Fn>(2) }
+            Function { name: Name(Text("b")), visibility: RawVisibilityId("pub(self)"), generic_params: GenericParamsId(4294967295), has_self_param: false, has_body: true, is_unsafe: true, params: [], is_varargs: false, ret_type: Tuple([]), ast_id: FileAstId::<syntax::ast::generated::nodes::Fn>(2) }
         "##]],
     );
 }
@@ -329,9 +329,9 @@ fn trait_attrs() {
             #[Attrs { entries: Some([Attr { path: ModPath { kind: Plain, segments: [Name(Text("trait_attr"))] }, input: None }]) }]
             Trait { name: Name(Text("Tr")), visibility: RawVisibilityId("pub(self)"), generic_params: GenericParamsId(0), auto: false, items: [Function(Idx::<Function>(0)), Function(Idx::<Function>(1))], ast_id: FileAstId::<syntax::ast::generated::nodes::Trait>(0) }
             > #[Attrs { entries: Some([Attr { path: ModPath { kind: Plain, segments: [Name(Text("attr_a"))] }, input: None }]) }]
-            > Function { name: Name(Text("a")), visibility: RawVisibilityId("pub(self)"), generic_params: GenericParamsId(4294967295), has_self_param: false, is_unsafe: false, params: [], is_varargs: false, ret_type: Tuple([]), ast_id: FileAstId::<syntax::ast::generated::nodes::Fn>(1) }
+            > Function { name: Name(Text("a")), visibility: RawVisibilityId("pub(self)"), generic_params: GenericParamsId(4294967295), has_self_param: false, has_body: true, is_unsafe: false, params: [], is_varargs: false, ret_type: Tuple([]), ast_id: FileAstId::<syntax::ast::generated::nodes::Fn>(1) }
             > #[Attrs { entries: Some([Attr { path: ModPath { kind: Plain, segments: [Name(Text("attr_b"))] }, input: None }]) }]
-            > Function { name: Name(Text("b")), visibility: RawVisibilityId("pub(self)"), generic_params: GenericParamsId(4294967295), has_self_param: false, is_unsafe: false, params: [], is_varargs: false, ret_type: Tuple([]), ast_id: FileAstId::<syntax::ast::generated::nodes::Fn>(2) }
+            > Function { name: Name(Text("b")), visibility: RawVisibilityId("pub(self)"), generic_params: GenericParamsId(4294967295), has_self_param: false, has_body: true, is_unsafe: false, params: [], is_varargs: false, ret_type: Tuple([]), ast_id: FileAstId::<syntax::ast::generated::nodes::Fn>(2) }
         "##]],
     );
 }
@@ -355,9 +355,9 @@ fn impl_attrs() {
             #[Attrs { entries: Some([Attr { path: ModPath { kind: Plain, segments: [Name(Text("impl_attr"))] }, input: None }]) }]
             Impl { generic_params: GenericParamsId(4294967295), target_trait: None, target_type: Path(Path { type_anchor: None, mod_path: ModPath { kind: Plain, segments: [Name(Text("Ty"))] }, generic_args: [None] }), is_negative: false, items: [Function(Idx::<Function>(0)), Function(Idx::<Function>(1))], ast_id: FileAstId::<syntax::ast::generated::nodes::Impl>(0) }
             > #[Attrs { entries: Some([Attr { path: ModPath { kind: Plain, segments: [Name(Text("attr_a"))] }, input: None }]) }]
-            > Function { name: Name(Text("a")), visibility: RawVisibilityId("pub(self)"), generic_params: GenericParamsId(4294967295), has_self_param: false, is_unsafe: false, params: [], is_varargs: false, ret_type: Tuple([]), ast_id: FileAstId::<syntax::ast::generated::nodes::Fn>(1) }
+            > Function { name: Name(Text("a")), visibility: RawVisibilityId("pub(self)"), generic_params: GenericParamsId(4294967295), has_self_param: false, has_body: true, is_unsafe: false, params: [], is_varargs: false, ret_type: Tuple([]), ast_id: FileAstId::<syntax::ast::generated::nodes::Fn>(1) }
             > #[Attrs { entries: Some([Attr { path: ModPath { kind: Plain, segments: [Name(Text("attr_b"))] }, input: None }]) }]
-            > Function { name: Name(Text("b")), visibility: RawVisibilityId("pub(self)"), generic_params: GenericParamsId(4294967295), has_self_param: false, is_unsafe: false, params: [], is_varargs: false, ret_type: Tuple([]), ast_id: FileAstId::<syntax::ast::generated::nodes::Fn>(2) }
+            > Function { name: Name(Text("b")), visibility: RawVisibilityId("pub(self)"), generic_params: GenericParamsId(4294967295), has_self_param: false, has_body: true, is_unsafe: false, params: [], is_varargs: false, ret_type: Tuple([]), ast_id: FileAstId::<syntax::ast::generated::nodes::Fn>(2) }
         "##]],
     );
 }
@@ -408,13 +408,13 @@ fn inner_item_attrs() {
             inner attrs: Attrs { entries: None }
 
             top-level items:
-            Function { name: Name(Text("foo")), visibility: RawVisibilityId("pub(self)"), generic_params: GenericParamsId(4294967295), has_self_param: false, is_unsafe: false, params: [], is_varargs: false, ret_type: Tuple([]), ast_id: FileAstId::<syntax::ast::generated::nodes::Fn>(0) }
+            Function { name: Name(Text("foo")), visibility: RawVisibilityId("pub(self)"), generic_params: GenericParamsId(4294967295), has_self_param: false, has_body: true, is_unsafe: false, params: [], is_varargs: false, ret_type: Tuple([]), ast_id: FileAstId::<syntax::ast::generated::nodes::Fn>(0) }
 
             inner items:
 
             for AST FileAstId::<syntax::ast::generated::nodes::Item>(1):
             #[Attrs { entries: Some([Attr { path: ModPath { kind: Plain, segments: [Name(Text("on_inner"))] }, input: None }]) }]
-            Function { name: Name(Text("inner")), visibility: RawVisibilityId("pub(self)"), generic_params: GenericParamsId(4294967295), has_self_param: false, is_unsafe: false, params: [], is_varargs: false, ret_type: Tuple([]), ast_id: FileAstId::<syntax::ast::generated::nodes::Fn>(1) }
+            Function { name: Name(Text("inner")), visibility: RawVisibilityId("pub(self)"), generic_params: GenericParamsId(4294967295), has_self_param: false, has_body: true, is_unsafe: false, params: [], is_varargs: false, ret_type: Tuple([]), ast_id: FileAstId::<syntax::ast::generated::nodes::Fn>(1) }
 
         "##]],
     );