Collapse term search exprs before Cartesian product to avoid OOM

crates/hir/src/term_search.rs

@@ -127,6 +127,13 @@ impl LookupTable {
             self.types_wishlist.insert(ty.clone());
         }
 
+        // Collapse suggestions if there are many
+        if let Some(res) = &res {
+            if res.len() > self.many_threshold {
+                return Some(vec![Expr::Many(ty.clone())]);
+            }
+        }
+
         res
     }
 
@@ -158,6 +165,13 @@ impl LookupTable {
             self.types_wishlist.insert(ty.clone());
         }
 
+        // Collapse suggestions if there are many
+        if let Some(res) = &res {
+            if res.len() > self.many_threshold {
+                return Some(vec![Expr::Many(ty.clone())]);
+            }
+        }
+
         res
     }
 
@@ -176,11 +190,11 @@ impl LookupTable {
             }
             None => {
                 self.data.insert(ty.clone(), AlternativeExprs::new(self.many_threshold, exprs));
-                for it in self.new_types.values_mut() {
-                    it.push(ty.clone());
-                }
             }
         }
+        for it in self.new_types.values_mut() {
+            it.push(ty.clone());
+        }
     }
 
     /// Iterate all the reachable types

crates/hir/src/term_search/expr.rs

@@ -211,13 +211,13 @@ impl Expr {
                 }
             }
             Expr::Method { func, target, params, .. } => {
-                if target.contains_many_in_illegal_pos() {
+                if self.contains_many_in_illegal_pos(db) {
                     return Ok(many_formatter(&target.ty(db)));
                 }
 
                 let func_name = func.name(db).display(db.upcast()).to_string();
                 let self_param = func.self_param(db).unwrap();
-                let target = target.gen_source_code(
+                let target_str = target.gen_source_code(
                     sema_scope,
                     many_formatter,
                     prefer_no_std,
@@ -236,9 +236,12 @@ impl Expr {
                     Some(trait_) => {
                         let trait_name = mod_item_path_str(sema_scope, &ModuleDef::Trait(trait_))?;
                         let target = match self_param.access(db) {
-                            crate::Access::Shared => format!("&{target}"),
+                            crate::Access::Shared if !target.is_many() => format!("&{target_str}"),
-                            crate::Access::Exclusive => format!("&mut {target}"),
+                            crate::Access::Exclusive if !target.is_many() => {
-                            crate::Access::Owned => target,
+                                format!("&mut {target_str}")
+                            }
+                            crate::Access::Owned => target_str,
+                            _ => many_formatter(&target.ty(db)),
                         };
                         let res = match args.is_empty() {
                             true => format!("{trait_name}::{func_name}({target})",),
@@ -246,7 +249,7 @@ impl Expr {
                         };
                         Ok(res)
                     }
-                    None => Ok(format!("{target}.{func_name}({args})")),
+                    None => Ok(format!("{target_str}.{func_name}({args})")),
                 }
             }
             Expr::Variant { variant, generics, params } => {
@@ -381,7 +384,7 @@ impl Expr {
                 Ok(res)
             }
             Expr::Field { expr, field } => {
-                if expr.contains_many_in_illegal_pos() {
+                if expr.contains_many_in_illegal_pos(db) {
                     return Ok(many_formatter(&expr.ty(db)));
                 }
 
@@ -395,7 +398,7 @@ impl Expr {
                 Ok(format!("{strukt}.{field}"))
             }
             Expr::Reference(expr) => {
-                if expr.contains_many_in_illegal_pos() {
+                if expr.contains_many_in_illegal_pos(db) {
                     return Ok(many_formatter(&expr.ty(db)));
                 }
 
@@ -466,10 +469,17 @@ impl Expr {
     /// macro!().bar()
     /// &macro!()
     /// ```
-    fn contains_many_in_illegal_pos(&self) -> bool {
+    fn contains_many_in_illegal_pos(&self, db: &dyn HirDatabase) -> bool {
         match self {
-            Expr::Method { target, .. } => target.contains_many_in_illegal_pos(),
+            Expr::Method { target, func, .. } => {
-            Expr::Field { expr, .. } => expr.contains_many_in_illegal_pos(),
+                match func.as_assoc_item(db).and_then(|it| it.container_or_implemented_trait(db)) {
+                    Some(_) => false,
+                    None => {
+                        target.is_many()
+                    }
+                }
+            }
+            Expr::Field { expr, .. } => expr.contains_many_in_illegal_pos(db),
             Expr::Reference(target) => target.is_many(),
             Expr::Many(_) => true,
             _ => false,

crates/ide-completion/src/render.rs

@@ -1808,8 +1808,7 @@ fn f() { A { bar: b$0 }; }
                 fn baz() [type]
                 ex baz() [type]
                 ex bar() [type]
-                ex A { bar: baz() }.bar [type]
+                ex A { bar: ... }.bar [type]
-                ex A { bar: bar() }.bar [type]
                 st A []
                 fn f() []
             "#]],
@@ -1947,8 +1946,8 @@ fn main() {
 }
             "#,
             expect![[r#"
-                ex core::ops::Deref::deref(&T(S)) (use core::ops::Deref) [type_could_unify]
                 ex core::ops::Deref::deref(&t) (use core::ops::Deref) [type_could_unify]
+                ex core::ops::Deref::deref(&T(S)) (use core::ops::Deref) [type_could_unify]
                 lc m [local]
                 lc t [local]
                 lc &t [type+local]
@@ -1997,8 +1996,8 @@ fn main() {
 }
             "#,
             expect![[r#"
-                ex core::ops::DerefMut::deref_mut(&mut T(S)) (use core::ops::DerefMut) [type_could_unify]
                 ex core::ops::DerefMut::deref_mut(&mut t) (use core::ops::DerefMut) [type_could_unify]
+                ex core::ops::DerefMut::deref_mut(&mut T(S)) (use core::ops::DerefMut) [type_could_unify]
                 lc m [local]
                 lc t [local]
                 lc &mut t [type+local]

crates/ide-diagnostics/src/handlers/typed_hole.rs

@@ -274,7 +274,7 @@ impl Foo for Baz {
 }
 fn asd() -> Bar {
     let a = Baz;
-    Foo::foo(a)
+    Foo::foo(_)
 }
 ",
         );
@@ -363,7 +363,7 @@ impl Foo for A {
 }
 fn main() {
     let a = A;
-    let c: Bar = Foo::foo(&a);
+    let c: Bar = Foo::foo(_);
 }"#,
         );
     }