Style hover messages a bit differently

src/tools/rust-analyzer/crates/hir/src/lib.rs

@@ -34,7 +34,10 @@
 
 mod display;
 
-use std::{mem::discriminant, ops::ControlFlow};
+use std::{
+    mem::discriminant,
+    ops::{ControlFlow, Not},
+};
 
 use arrayvec::ArrayVec;
 use base_db::{CrateDisplayName, CrateId, CrateOrigin};
@@ -2697,6 +2700,18 @@ pub fn dyn_compatibility(&self, db: &dyn HirDatabase) -> Option<DynCompatibility
         hir_ty::dyn_compatibility::dyn_compatibility(db, self.id)
     }
 
+    pub fn dyn_compatibility_all_violations(
+        &self,
+        db: &dyn HirDatabase,
+    ) -> Option<Vec<DynCompatibilityViolation>> {
+        let mut violations = vec![];
+        hir_ty::dyn_compatibility::dyn_compatibility_with_callback(db, self.id, &mut |violation| {
+            violations.push(violation);
+            ControlFlow::Continue(())
+        });
+        violations.is_empty().not().then_some(violations)
+    }
+
     fn all_macro_calls(&self, db: &dyn HirDatabase) -> Box<[(AstId<ast::Item>, MacroCallId)]> {
         db.trait_data(self.id)
             .macro_calls

src/tools/rust-analyzer/crates/ide/src/hover/render.rs

@@ -273,7 +273,7 @@ pub(super) fn keyword(
     let markup = process_markup(
         sema.db,
         Definition::Module(doc_owner),
-        &markup(Some(docs.into()), description, None),
+        &markup(Some(docs.into()), description, None, None),
         config,
     );
     Some(HoverResult { markup, actions })
@@ -539,28 +539,29 @@ pub(super) fn definition(
         _ => None,
     };
 
-    let mut desc = String::new();
-    if let Some(notable_traits) = render_notable_trait_comment(db, notable_traits, edition) {
-        desc.push_str(&notable_traits);
-        desc.push('\n');
-    }
+    let mut extra = String::new();
     if hovered_definition {
+        if let Some(notable_traits) = render_notable_trait(db, notable_traits, edition) {
+            extra.push_str("\n___\n");
+            extra.push_str(&notable_traits);
+        }
         if let Some(layout_info) = layout_info() {
-            desc.push_str(&layout_info);
-            desc.push('\n');
+            extra.push_str("\n___\n");
+            extra.push_str(&layout_info);
         }
         if let Some(dyn_compatibility_info) = dyn_compatibility_info() {
-            desc.push_str(&dyn_compatibility_info);
-            desc.push('\n');
+            extra.push_str("\n___\n");
+            extra.push_str(&dyn_compatibility_info);
         }
     }
+    let mut desc = String::new();
     desc.push_str(&label);
     if let Some(value) = value() {
         desc.push_str(" = ");
         desc.push_str(&value);
     }
 
-    markup(docs.map(Into::into), desc, mod_path)
+    markup(docs.map(Into::into), desc, extra.is_empty().not().then_some(extra), mod_path)
 }
 
 pub(super) fn literal(
@@ -630,7 +631,7 @@ pub(super) fn literal(
     Some(s.into())
 }
 
-fn render_notable_trait_comment(
+fn render_notable_trait(
     db: &RootDatabase,
     notable_traits: &[(Trait, Vec<(Option<Type>, Name)>)],
     edition: Edition,
@@ -639,7 +640,7 @@ fn render_notable_trait_comment(
     let mut needs_impl_header = true;
     for (trait_, assoc_types) in notable_traits {
         desc.push_str(if mem::take(&mut needs_impl_header) {
-            "// Implements notable traits: "
+            "Implements notable traits: "
         } else {
             ", "
         });
@@ -732,13 +733,12 @@ fn type_info(
         )
         .into()
     } else {
-        let mut desc =
-            match render_notable_trait_comment(db, &notable_traits(db, &original), edition) {
-                Some(desc) => desc + "\n",
-                None => String::new(),
+        let mut desc = format!("```rust\n{}\n```", original.display(db, edition));
+        if let Some(extra) = render_notable_trait(db, &notable_traits(db, &original), edition) {
+            desc.push_str("\n___\n");
+            desc.push_str(&extra);
         };
-        format_to!(desc, "{}", original.display(db, edition));
-        Markup::fenced_block(&desc)
+        desc.into()
     };
     if let Some(actions) = HoverAction::goto_type_from_targets(db, targets, edition) {
         res.actions.push(actions);
@@ -790,20 +790,16 @@ fn closure_ty(
     };
     let mut markup = format!("```rust\n{}", c.display_with_id(sema.db, edition));
 
-    if let Some(layout) =
-        render_memory_layout(config.memory_layout, || original.layout(sema.db), |_| None, |_| None)
-    {
-        format_to!(markup, " {layout}");
-    }
     if let Some(trait_) = c.fn_trait(sema.db).get_id(sema.db, original.krate(sema.db).into()) {
         push_new_def(hir::Trait::from(trait_).into())
     }
-    format_to!(
-        markup,
-        "\n{}\n```{adjusted}\n\n## Captures\n{}",
-        c.display_with_impl(sema.db, edition),
-        captures_rendered,
-    );
+    format_to!(markup, "\n{}\n```", c.display_with_impl(sema.db, edition),);
+    if let Some(layout) =
+        render_memory_layout(config.memory_layout, || original.layout(sema.db), |_| None, |_| None)
+    {
+        format_to!(markup, "\n___\n{layout}");
+    }
+    format_to!(markup, "{adjusted}\n\n## Captures\n{}", captures_rendered,);
 
     let mut res = HoverResult::default();
     if let Some(actions) = HoverAction::goto_type_from_targets(sema.db, targets, edition) {
@@ -828,7 +824,12 @@ fn definition_mod_path(db: &RootDatabase, def: &Definition, edition: Edition) ->
         .map(|module| path(db, module, definition_owner_name(db, def, edition), edition))
 }
 
-fn markup(docs: Option<String>, desc: String, mod_path: Option<String>) -> Markup {
+fn markup(
+    docs: Option<String>,
+    rust: String,
+    extra: Option<String>,
+    mod_path: Option<String>,
+) -> Markup {
     let mut buf = String::new();
 
     if let Some(mod_path) = mod_path {
@@ -836,7 +837,11 @@ fn markup(docs: Option<String>, desc: String, mod_path: Option<String>) -> Marku
             format_to!(buf, "```rust\n{}\n```\n\n", mod_path);
         }
     }
-    format_to!(buf, "```rust\n{}\n```", desc);
+    format_to!(buf, "```rust\n{}\n```", rust);
+
+    if let Some(extra) = extra {
+        buf.push_str(&extra);
+    }
 
     if let Some(doc) = docs {
         format_to!(buf, "\n___\n\n{}", doc);
@@ -866,7 +871,7 @@ fn render_memory_layout(
     let config = config?;
     let layout = layout().ok()?;
 
-    let mut label = String::from("// ");
+    let mut label = String::new();
 
     if let Some(render) = config.size {
         let size = match tag(&layout) {
@@ -998,10 +1003,10 @@ fn render_dyn_compatibility(
     safety: Option<DynCompatibilityViolation>,
 ) {
     let Some(osv) = safety else {
-        buf.push_str("// Is Dyn compatible");
+        buf.push_str("Is Dyn compatible");
         return;
     };
-    buf.push_str("// Is not Dyn compatible due to ");
+    buf.push_str("Is not Dyn compatible due to ");
     match osv {
         DynCompatibilityViolation::SizedSelf => {
             buf.push_str("having a `Self: Sized` bound");