use std::iter::once; use hir::{ Adt, AsAssocItem, AssocItemContainer, Documentation, FieldSource, HasSource, HirDisplay, ModuleDef, ModuleSource, Semantics, }; use itertools::Itertools; use ra_db::SourceDatabase; use ra_ide_db::{ defs::{classify_name, classify_name_ref, Definition}, RootDatabase, }; use ra_syntax::{ast, match_ast, AstNode, SyntaxKind::*, SyntaxToken, TokenAtOffset}; use crate::{ display::{macro_label, rust_code_markup, rust_code_markup_with_doc, ShortLabel, ToNav}, FilePosition, NavigationTarget, RangeInfo, }; #[derive(Clone, Debug, PartialEq, Eq)] pub struct HoverConfig { pub implementations: bool, } impl Default for HoverConfig { fn default() -> Self { Self { implementations: true } } } impl HoverConfig { pub const NO_ACTIONS: Self = Self { implementations: false }; pub fn any(&self) -> bool { self.implementations } pub fn none(&self) -> bool { !self.any() } } #[derive(Debug, Clone)] pub enum HoverAction { Implementaion(FilePosition), } /// Contains the results when hovering over an item #[derive(Debug, Default)] pub struct HoverResult { results: Vec, actions: Vec, } impl HoverResult { pub fn new() -> HoverResult { Self::default() } pub fn extend(&mut self, item: Option) { self.results.extend(item); } pub fn is_empty(&self) -> bool { self.results.is_empty() } pub fn len(&self) -> usize { self.results.len() } pub fn first(&self) -> Option<&str> { self.results.first().map(String::as_str) } pub fn results(&self) -> &[String] { &self.results } pub fn actions(&self) -> &[HoverAction] { &self.actions } pub fn push_action(&mut self, action: HoverAction) { self.actions.push(action); } /// Returns the results converted into markup /// for displaying in a UI /// /// Does not process actions! pub fn to_markup(&self) -> String { self.results.join("\n\n___\n") } } // Feature: Hover // // Shows additional information, like type of an expression or documentation for definition when "focusing" code. // Focusing is usually hovering with a mouse, but can also be triggered with a shortcut. pub(crate) fn hover(db: &RootDatabase, position: FilePosition) -> Option> { let sema = Semantics::new(db); let file = sema.parse(position.file_id).syntax().clone(); let token = pick_best(file.token_at_offset(position.offset))?; let token = sema.descend_into_macros(token); let mut res = HoverResult::new(); if let Some((node, name_kind)) = match_ast! { match (token.parent()) { ast::NameRef(name_ref) => { classify_name_ref(&sema, &name_ref).map(|d| (name_ref.syntax().clone(), d.definition())) }, ast::Name(name) => { classify_name(&sema, &name).map(|d| (name.syntax().clone(), d.definition())) }, _ => None, } } { let range = sema.original_range(&node).range; res.extend(hover_text_from_name_kind(db, name_kind)); if !res.is_empty() { if let Some(action) = show_implementations_action(db, name_kind) { res.push_action(action); } return Some(RangeInfo::new(range, res)); } } let node = token .ancestors() .find(|n| ast::Expr::cast(n.clone()).is_some() || ast::Pat::cast(n.clone()).is_some())?; let ty = match_ast! { match node { ast::MacroCall(_it) => { // If this node is a MACRO_CALL, it means that `descend_into_macros` failed to resolve. // (e.g expanding a builtin macro). So we give up here. return None; }, ast::Expr(it) => { sema.type_of_expr(&it) }, ast::Pat(it) => { sema.type_of_pat(&it) }, _ => None, } }?; res.extend(Some(rust_code_markup(&ty.display(db)))); let range = sema.original_range(&node).range; Some(RangeInfo::new(range, res)) } fn show_implementations_action(db: &RootDatabase, def: Definition) -> Option { fn to_action(nav_target: NavigationTarget) -> HoverAction { HoverAction::Implementaion(FilePosition { file_id: nav_target.file_id(), offset: nav_target.range().start(), }) } match def { Definition::ModuleDef(it) => match it { ModuleDef::Adt(Adt::Struct(it)) => Some(to_action(it.to_nav(db))), ModuleDef::Adt(Adt::Union(it)) => Some(to_action(it.to_nav(db))), ModuleDef::Adt(Adt::Enum(it)) => Some(to_action(it.to_nav(db))), ModuleDef::Trait(it) => Some(to_action(it.to_nav(db))), _ => None, }, _ => None, } } fn hover_text( docs: Option, desc: Option, mod_path: Option, ) -> Option { if let Some(desc) = desc { Some(rust_code_markup_with_doc(&desc, docs.as_deref(), mod_path.as_deref())) } else { docs } } fn definition_owner_name(db: &RootDatabase, def: &Definition) -> Option { match def { Definition::Field(f) => Some(f.parent_def(db).name(db)), Definition::Local(l) => l.parent(db).name(db), Definition::ModuleDef(md) => match md { ModuleDef::Function(f) => match f.as_assoc_item(db)?.container(db) { AssocItemContainer::Trait(t) => Some(t.name(db)), AssocItemContainer::ImplDef(i) => i.target_ty(db).as_adt().map(|adt| adt.name(db)), }, ModuleDef::EnumVariant(e) => Some(e.parent_enum(db).name(db)), _ => None, }, Definition::SelfType(i) => i.target_ty(db).as_adt().map(|adt| adt.name(db)), _ => None, } .map(|name| name.to_string()) } fn determine_mod_path(db: &RootDatabase, def: &Definition) -> Option { let mod_path = def.module(db).map(|module| { once(db.crate_graph()[module.krate().into()].display_name.as_ref().map(ToString::to_string)) .chain( module .path_to_root(db) .into_iter() .rev() .map(|it| it.name(db).map(|name| name.to_string())), ) .chain(once(definition_owner_name(db, def))) .flatten() .join("::") }); mod_path } fn hover_text_from_name_kind(db: &RootDatabase, def: Definition) -> Option { let mod_path = determine_mod_path(db, &def); return match def { Definition::Macro(it) => { let src = it.source(db); let docs = Documentation::from_ast(&src.value).map(Into::into); hover_text(docs, Some(macro_label(&src.value)), mod_path) } Definition::Field(it) => { let src = it.source(db); match src.value { FieldSource::Named(it) => { let docs = Documentation::from_ast(&it).map(Into::into); hover_text(docs, it.short_label(), mod_path) } _ => None, } } Definition::ModuleDef(it) => match it { ModuleDef::Module(it) => match it.definition_source(db).value { ModuleSource::Module(it) => { let docs = Documentation::from_ast(&it).map(Into::into); hover_text(docs, it.short_label(), mod_path) } _ => None, }, ModuleDef::Function(it) => from_def_source(db, it, mod_path), ModuleDef::Adt(Adt::Struct(it)) => from_def_source(db, it, mod_path), ModuleDef::Adt(Adt::Union(it)) => from_def_source(db, it, mod_path), ModuleDef::Adt(Adt::Enum(it)) => from_def_source(db, it, mod_path), ModuleDef::EnumVariant(it) => from_def_source(db, it, mod_path), ModuleDef::Const(it) => from_def_source(db, it, mod_path), ModuleDef::Static(it) => from_def_source(db, it, mod_path), ModuleDef::Trait(it) => from_def_source(db, it, mod_path), ModuleDef::TypeAlias(it) => from_def_source(db, it, mod_path), ModuleDef::BuiltinType(it) => Some(it.to_string()), }, Definition::Local(it) => Some(rust_code_markup(&it.ty(db).display(db))), Definition::TypeParam(_) | Definition::SelfType(_) => { // FIXME: Hover for generic param None } }; fn from_def_source(db: &RootDatabase, def: D, mod_path: Option) -> Option where D: HasSource, A: ast::DocCommentsOwner + ast::NameOwner + ShortLabel + ast::AttrsOwner, { let src = def.source(db); let docs = Documentation::from_ast(&src.value).map(Into::into); hover_text(docs, src.value.short_label(), mod_path) } } fn pick_best(tokens: TokenAtOffset) -> Option { return tokens.max_by_key(priority); fn priority(n: &SyntaxToken) -> usize { match n.kind() { IDENT | INT_NUMBER => 3, L_PAREN | R_PAREN => 2, kind if kind.is_trivia() => 0, _ => 1, } } } #[cfg(test)] mod tests { use super::*; use ra_db::FileLoader; use ra_syntax::TextRange; use crate::mock_analysis::{analysis_and_position, single_file_with_position}; fn trim_markup(s: &str) -> &str { s.trim_start_matches("```rust\n").trim_end_matches("\n```") } fn trim_markup_opt(s: Option<&str>) -> Option<&str> { s.map(trim_markup) } fn assert_impl_action(action: &HoverAction, position: u32) { let offset = match action { HoverAction::Implementaion(pos) => pos.offset, }; assert_eq!(offset, position.into()); } fn check_hover_result(fixture: &str, expected: &[&str]) -> (String, Vec) { let (analysis, position) = analysis_and_position(fixture); let hover = analysis.hover(position).unwrap().unwrap(); let mut results = Vec::from(hover.info.results()); results.sort(); for (markup, expected) in results.iter().zip(expected.iter().chain(std::iter::repeat(&""))) { assert_eq!(trim_markup(&markup), *expected); } assert_eq!(hover.info.len(), expected.len()); let content = analysis.db.file_text(position.file_id); (content[hover.range].to_string(), hover.info.actions().to_vec()) } fn check_hover_no_result(fixture: &str) { let (analysis, position) = analysis_and_position(fixture); assert!(analysis.hover(position).unwrap().is_none()); } #[test] fn hover_shows_type_of_an_expression() { let (analysis, position) = single_file_with_position( " pub fn foo() -> u32 { 1 } fn main() { let foo_test = foo()<|>; } ", ); let hover = analysis.hover(position).unwrap().unwrap(); assert_eq!(hover.range, TextRange::new(95.into(), 100.into())); assert_eq!(trim_markup_opt(hover.info.first()), Some("u32")); } #[test] fn hover_shows_long_type_of_an_expression() { check_hover_result( r#" //- /main.rs struct Scan { a: A, b: B, c: C, } struct FakeIter { inner: I, } struct OtherStruct { i: T, } enum FakeOption { Some(T), None, } fn scan(a: A, b: B, c: C) -> FakeIter, B, C>> { FakeIter { inner: Scan { a, b, c } } } fn main() { let num: i32 = 55; let closure = |memo: &mut u32, value: &u32, _another: &mut u32| -> FakeOption { FakeOption::Some(*memo + value) }; let number = 5u32; let mut iter<|> = scan(OtherStruct { i: num }, closure, number); } "#, &["FakeIter>, |&mut u32, &u32, &mut u32| -> FakeOption, u32>>"], ); } #[test] fn hover_shows_fn_signature() { // Single file with result check_hover_result( r#" //- /main.rs pub fn foo() -> u32 { 1 } fn main() { let foo_test = fo<|>o(); } "#, &["pub fn foo() -> u32"], ); // Multiple candidates but results are ambiguous. check_hover_result( r#" //- /a.rs pub fn foo() -> u32 { 1 } //- /b.rs pub fn foo() -> &str { "" } //- /c.rs pub fn foo(a: u32, b: u32) {} //- /main.rs mod a; mod b; mod c; fn main() { let foo_test = fo<|>o(); } "#, &["{unknown}"], ); } #[test] fn hover_shows_fn_signature_with_type_params() { check_hover_result( r#" //- /main.rs pub fn foo<'a, T: AsRef>(b: &'a T) -> &'a str { } fn main() { let foo_test = fo<|>o(); } "#, &["pub fn foo<'a, T: AsRef>(b: &'a T) -> &'a str"], ); } #[test] fn hover_shows_fn_signature_on_fn_name() { check_hover_result( r#" //- /main.rs pub fn foo<|>(a: u32, b: u32) -> u32 {} fn main() { } "#, &["pub fn foo(a: u32, b: u32) -> u32"], ); } #[test] fn hover_shows_struct_field_info() { // Hovering over the field when instantiating check_hover_result( r#" //- /main.rs struct Foo { field_a: u32, } fn main() { let foo = Foo { field_a<|>: 0, }; } "#, &["Foo\n```\n\n```rust\nfield_a: u32"], ); // Hovering over the field in the definition check_hover_result( r#" //- /main.rs struct Foo { field_a<|>: u32, } fn main() { let foo = Foo { field_a: 0, }; } "#, &["Foo\n```\n\n```rust\nfield_a: u32"], ); } #[test] fn hover_const_static() { check_hover_result( r#" //- /main.rs const foo<|>: u32 = 0; "#, &["const foo: u32"], ); check_hover_result( r#" //- /main.rs static foo<|>: u32 = 0; "#, &["static foo: u32"], ); } #[test] fn hover_default_generic_types() { check_hover_result( r#" //- /main.rs struct Test { k: K, t: T, } fn main() { let zz<|> = Test { t: 23u8, k: 33 }; }"#, &["Test"], ); } #[test] fn hover_some() { let (analysis, position) = single_file_with_position( " enum Option { Some(T) } use Option::Some; fn main() { So<|>me(12); } ", ); let hover = analysis.hover(position).unwrap().unwrap(); assert_eq!(trim_markup_opt(hover.info.first()), Some("Option\n```\n\n```rust\nSome")); let (analysis, position) = single_file_with_position( " enum Option { Some(T) } use Option::Some; fn main() { let b<|>ar = Some(12); } ", ); let hover = analysis.hover(position).unwrap().unwrap(); assert_eq!(trim_markup_opt(hover.info.first()), Some("Option")); } #[test] fn hover_enum_variant() { check_hover_result( r#" //- /main.rs enum Option { /// The None variant Non<|>e } "#, &[" Option ``` ```rust None ``` ___ The None variant " .trim()], ); check_hover_result( r#" //- /main.rs enum Option { /// The Some variant Some(T) } fn main() { let s = Option::Som<|>e(12); } "#, &[" Option ``` ```rust Some ``` ___ The Some variant " .trim()], ); } #[test] fn hover_for_local_variable() { let (analysis, position) = single_file_with_position("fn func(foo: i32) { fo<|>o; }"); let hover = analysis.hover(position).unwrap().unwrap(); assert_eq!(trim_markup_opt(hover.info.first()), Some("i32")); } #[test] fn hover_for_local_variable_pat() { let (analysis, position) = single_file_with_position("fn func(fo<|>o: i32) {}"); let hover = analysis.hover(position).unwrap().unwrap(); assert_eq!(trim_markup_opt(hover.info.first()), Some("i32")); } #[test] fn hover_local_var_edge() { let (analysis, position) = single_file_with_position( " fn func(foo: i32) { if true { <|>foo; }; } ", ); let hover = analysis.hover(position).unwrap().unwrap(); assert_eq!(trim_markup_opt(hover.info.first()), Some("i32")); } #[test] fn hover_for_param_edge() { let (analysis, position) = single_file_with_position("fn func(<|>foo: i32) {}"); let hover = analysis.hover(position).unwrap().unwrap(); assert_eq!(trim_markup_opt(hover.info.first()), Some("i32")); } #[test] fn test_hover_infer_associated_method_result() { let (analysis, position) = single_file_with_position( " struct Thing { x: u32 } impl Thing { fn new() -> Thing { Thing { x: 0 } } } fn main() { let foo_<|>test = Thing::new(); } ", ); let hover = analysis.hover(position).unwrap().unwrap(); assert_eq!(trim_markup_opt(hover.info.first()), Some("Thing")); } #[test] fn test_hover_infer_associated_method_exact() { let (analysis, position) = single_file_with_position( " mod wrapper { struct Thing { x: u32 } impl Thing { fn new() -> Thing { Thing { x: 0 } } } } fn main() { let foo_test = wrapper::Thing::new<|>(); } ", ); let hover = analysis.hover(position).unwrap().unwrap(); assert_eq!( trim_markup_opt(hover.info.first()), Some("wrapper::Thing\n```\n\n```rust\nfn new() -> Thing") ); } #[test] fn test_hover_infer_associated_const_in_pattern() { let (analysis, position) = single_file_with_position( " struct X; impl X { const C: u32 = 1; } fn main() { match 1 { X::C<|> => {}, 2 => {}, _ => {} }; } ", ); let hover = analysis.hover(position).unwrap().unwrap(); assert_eq!(trim_markup_opt(hover.info.first()), Some("const C: u32")); } #[test] fn test_hover_self() { let (analysis, position) = single_file_with_position( " struct Thing { x: u32 } impl Thing { fn new() -> Self { Self<|> { x: 0 } } } ", ); let hover = analysis.hover(position).unwrap().unwrap(); assert_eq!(trim_markup_opt(hover.info.first()), Some("Thing")); /* FIXME: revive these tests let (analysis, position) = single_file_with_position( " struct Thing { x: u32 } impl Thing { fn new() -> Self<|> { Self { x: 0 } } } ", ); let hover = analysis.hover(position).unwrap().unwrap(); assert_eq!(trim_markup_opt(hover.info.first()), Some("Thing")); let (analysis, position) = single_file_with_position( " enum Thing { A } impl Thing { pub fn new() -> Self<|> { Thing::A } } ", ); let hover = analysis.hover(position).unwrap().unwrap(); assert_eq!(trim_markup_opt(hover.info.first()), Some("enum Thing")); let (analysis, position) = single_file_with_position( " enum Thing { A } impl Thing { pub fn thing(a: Self<|>) { } } ", ); let hover = analysis.hover(position).unwrap().unwrap(); assert_eq!(trim_markup_opt(hover.info.first()), Some("enum Thing")); */ } #[test] fn test_hover_shadowing_pat() { let (analysis, position) = single_file_with_position( " fn x() {} fn y() { let x = 0i32; x<|>; } ", ); let hover = analysis.hover(position).unwrap().unwrap(); assert_eq!(trim_markup_opt(hover.info.first()), Some("i32")); } #[test] fn test_hover_macro_invocation() { let (analysis, position) = single_file_with_position( " macro_rules! foo { () => {} } fn f() { fo<|>o!(); } ", ); let hover = analysis.hover(position).unwrap().unwrap(); assert_eq!(trim_markup_opt(hover.info.first()), Some("macro_rules! foo")); } #[test] fn test_hover_tuple_field() { let (analysis, position) = single_file_with_position( " struct TS(String, i32<|>); ", ); let hover = analysis.hover(position).unwrap().unwrap(); assert_eq!(trim_markup_opt(hover.info.first()), Some("i32")); } #[test] fn test_hover_through_macro() { let (hover_on, _) = check_hover_result( " //- /lib.rs macro_rules! id { ($($tt:tt)*) => { $($tt)* } } fn foo() {} id! { fn bar() { fo<|>o(); } } ", &["fn foo()"], ); assert_eq!(hover_on, "foo") } #[test] fn test_hover_through_expr_in_macro() { let (hover_on, _) = check_hover_result( " //- /lib.rs macro_rules! id { ($($tt:tt)*) => { $($tt)* } } fn foo(bar:u32) { let a = id!(ba<|>r); } ", &["u32"], ); assert_eq!(hover_on, "bar") } #[test] fn test_hover_through_expr_in_macro_recursive() { let (hover_on, _) = check_hover_result( " //- /lib.rs macro_rules! id_deep { ($($tt:tt)*) => { $($tt)* } } macro_rules! id { ($($tt:tt)*) => { id_deep!($($tt)*) } } fn foo(bar:u32) { let a = id!(ba<|>r); } ", &["u32"], ); assert_eq!(hover_on, "bar") } #[test] fn test_hover_through_func_in_macro_recursive() { let (hover_on, _) = check_hover_result( " //- /lib.rs macro_rules! id_deep { ($($tt:tt)*) => { $($tt)* } } macro_rules! id { ($($tt:tt)*) => { id_deep!($($tt)*) } } fn bar() -> u32 { 0 } fn foo() { let a = id!([0u32, bar(<|>)] ); } ", &["u32"], ); assert_eq!(hover_on, "bar()") } #[test] fn test_hover_through_literal_string_in_macro() { let (hover_on, _) = check_hover_result( r#" //- /lib.rs macro_rules! arr { ($($tt:tt)*) => { [$($tt)*)] } } fn foo() { let mastered_for_itunes = ""; let _ = arr!("Tr<|>acks", &mastered_for_itunes); } "#, &["&str"], ); assert_eq!(hover_on, "\"Tracks\""); } #[test] fn test_hover_through_assert_macro() { let (hover_on, _) = check_hover_result( r#" //- /lib.rs #[rustc_builtin_macro] macro_rules! assert {} fn bar() -> bool { true } fn foo() { assert!(ba<|>r()); } "#, &["fn bar() -> bool"], ); assert_eq!(hover_on, "bar"); } #[test] fn test_hover_through_literal_string_in_builtin_macro() { check_hover_no_result( r#" //- /lib.rs #[rustc_builtin_macro] macro_rules! format {} fn foo() { format!("hel<|>lo {}", 0); } "#, ); } #[test] fn test_hover_non_ascii_space_doc() { check_hover_result( " //- /lib.rs /// <- `\u{3000}` here fn foo() { } fn bar() { fo<|>o(); } ", &["fn foo()\n```\n___\n\n<- `\u{3000}` here"], ); } #[test] fn test_hover_function_show_qualifiers() { check_hover_result( " //- /lib.rs async fn foo<|>() {} ", &["async fn foo()"], ); check_hover_result( " //- /lib.rs pub const unsafe fn foo<|>() {} ", &["pub const unsafe fn foo()"], ); check_hover_result( r#" //- /lib.rs pub(crate) async unsafe extern "C" fn foo<|>() {} "#, &[r#"pub(crate) async unsafe extern "C" fn foo()"#], ); } #[test] fn test_hover_trait_show_qualifiers() { let (_, actions) = check_hover_result( " //- /lib.rs unsafe trait foo<|>() {} ", &["unsafe trait foo"], ); assert_impl_action(&actions[0], 13); } #[test] fn test_hover_mod_with_same_name_as_function() { check_hover_result( " //- /lib.rs use self::m<|>y::Bar; mod my { pub struct Bar; } fn my() {} ", &["mod my"], ); } #[test] fn test_hover_struct_doc_comment() { check_hover_result( r#" //- /lib.rs /// bar docs struct Bar; fn foo() { let bar = Ba<|>r; } "#, &["struct Bar\n```\n___\n\nbar docs"], ); } #[test] fn test_hover_struct_doc_attr() { check_hover_result( r#" //- /lib.rs #[doc = "bar docs"] struct Bar; fn foo() { let bar = Ba<|>r; } "#, &["struct Bar\n```\n___\n\nbar docs"], ); } #[test] fn test_hover_struct_doc_attr_multiple_and_mixed() { check_hover_result( r#" //- /lib.rs /// bar docs 0 #[doc = "bar docs 1"] #[doc = "bar docs 2"] struct Bar; fn foo() { let bar = Ba<|>r; } "#, &["struct Bar\n```\n___\n\nbar docs 0\n\nbar docs 1\n\nbar docs 2"], ); } #[test] fn test_hover_macro_generated_struct_fn_doc_comment() { check_hover_result( r#" //- /lib.rs macro_rules! bar { () => { struct Bar; impl Bar { /// Do the foo fn foo(&self) {} } } } bar!(); fn foo() { let bar = Bar; bar.fo<|>o(); } "#, &["Bar\n```\n\n```rust\nfn foo(&self)\n```\n___\n\n Do the foo"], ); } #[test] fn test_hover_macro_generated_struct_fn_doc_attr() { check_hover_result( r#" //- /lib.rs macro_rules! bar { () => { struct Bar; impl Bar { #[doc = "Do the foo"] fn foo(&self) {} } } } bar!(); fn foo() { let bar = Bar; bar.fo<|>o(); } "#, &["Bar\n```\n\n```rust\nfn foo(&self)\n```\n___\n\nDo the foo"], ); } #[test] fn test_hover_trait_has_impl_action() { let (_, actions) = check_hover_result( " //- /lib.rs trait foo<|>() {} ", &["trait foo"], ); assert_impl_action(&actions[0], 6); } #[test] fn test_hover_struct_has_impl_action() { let (_, actions) = check_hover_result( " //- /lib.rs struct foo<|>() {} ", &["struct foo"], ); assert_impl_action(&actions[0], 7); } #[test] fn test_hover_union_has_impl_action() { let (_, actions) = check_hover_result( " //- /lib.rs union foo<|>() {} ", &["union foo"], ); assert_impl_action(&actions[0], 6); } #[test] fn test_hover_enum_has_impl_action() { let (_, actions) = check_hover_result( " //- /lib.rs enum foo<|>() { A, B } ", &["enum foo"], ); assert_impl_action(&actions[0], 5); } }