diff --git a/crates/ide/src/hover/render.rs b/crates/ide/src/hover/render.rs index d29833a65b..a80d08308a 100644 --- a/crates/ide/src/hover/render.rs +++ b/crates/ide/src/hover/render.rs @@ -239,22 +239,20 @@ pub(super) fn keyword( } let parent = token.parent()?; let famous_defs = FamousDefs(sema, sema.scope(&parent).krate()); - let keyword_mod = if token.kind() == T![fn] && ast::FnPtrType::cast(parent).is_some() { - // treat fn keyword inside function pointer type as primitive - format!("prim_{}", token.text()) - } else { - // std exposes {}_keyword modules with docstrings on the root to document keywords - format!("{}_keyword", token.text()) - }; - let doc_owner = find_std_module(&famous_defs, &keyword_mod)?; + + // some keywords get fancy type tooltips if they are apart of an expression, which require some extra work + // panic safety: we just checked that token is a keyword, and we have it's parent in scope, so it must have a parent + let KeywordHint { description, documentation, actions } = keyword_hints(sema, token); + + let doc_owner = find_std_module(&famous_defs, &documentation)?; let docs = doc_owner.attrs(sema.db).docs()?; let markup = process_markup( sema.db, Definition::Module(doc_owner), - &markup(Some(docs.into()), token.text().into(), None)?, + &markup(Some(docs.into()), description, None)?, config, ); - Some(HoverResult { markup, actions: Default::default() }) + Some(HoverResult { markup, actions }) } pub(super) fn try_for_lint(attr: &ast::Attr, token: &SyntaxToken) -> Option { @@ -500,3 +498,94 @@ fn local(db: &RootDatabase, it: hir::Local) -> Option { }; markup(None, desc, None) } + +struct KeywordHint { + description: String, + documentation: String, + actions: Vec, +} + +impl KeywordHint { + fn new(description: String, documentation: String) -> Self { + Self { description, documentation, actions: Vec::default() } + } +} + +/// Panics +/// ------ +/// `token` is assumed to: +/// - have a parent, and +/// - be a keyword +fn keyword_hints<'t>(sema: &Semantics, token: &'t SyntaxToken) -> KeywordHint { + let parent = token.parent().expect("token was assumed to have a parent, but had none"); + + macro_rules! create_hint { + ($ty_info:expr, $doc:expr) => {{ + let documentation = $doc; + match $ty_info { + Some(ty) => { + let mut targets: Vec = Vec::new(); + let mut push_new_def = |item: hir::ModuleDef| { + if !targets.contains(&item) { + targets.push(item); + } + }; + walk_and_push_ty(sema.db, &ty.original, &mut push_new_def); + + let ty = ty.adjusted(); + let description = format!("{}: {}", token.text(), ty.display(sema.db)); + + KeywordHint { + description, + documentation, + actions: vec![HoverAction::goto_type_from_targets(sema.db, targets)], + } + } + None => KeywordHint { + description: token.text().to_string(), + documentation, + actions: Vec::new(), + }, + } + }}; + } + + match token.kind() { + T![await] | T![loop] | T![match] | T![unsafe] => { + let ty = ast::Expr::cast(parent).and_then(|site| sema.type_of_expr(&site)); + create_hint!(ty, format!("{}_keyword", token.text())) + } + + T![if] | T![else] => { + fn if_has_else(site: &ast::IfExpr) -> bool { + match site.else_branch() { + Some(ast::ElseBranch::IfExpr(inner)) => if_has_else(&inner), + Some(ast::ElseBranch::Block(_)) => true, + None => false, + } + } + + // only include the type if there is an else branch; it isn't worth annotating + // an expression that always returns `()`, is it? + let ty = ast::IfExpr::cast(parent) + .and_then(|site| if_has_else(&site).then(|| site)) + .and_then(|site| sema.type_of_expr(&ast::Expr::IfExpr(site))); + create_hint!(ty, format!("{}_keyword", token.text())) + } + + T![fn] => { + let module = match ast::FnPtrType::cast(parent) { + // treat fn keyword inside function pointer type as primitive + Some(_) => format!("prim_{}", token.text()), + None => format!("{}_keyword", token.text()), + }; + KeywordHint::new(token.text().to_string(), module) + } + + kind if kind.is_keyword() => { + KeywordHint::new(token.text().to_string(), format!("{}_keyword", token.text())) + } + + _ => panic!("{} was assumed to be a keyword, but it wasn't", token), + } +}