Use CompactString for Identifier

Cargo.toml

@@ -55,6 +55,7 @@ colored = { version = "2.1.0" }
 console_error_panic_hook = { version = "0.1.7" }
 console_log = { version = "1.0.0" }
 countme = { version = "3.0.1" }
+compact_str = "0.7.1"
 criterion = { version = "0.5.1", default-features = false }
 crossbeam = { version = "0.8.4" }
 dashmap = { version = "5.5.3" }

crates/red_knot/src/lib.rs

@@ -1,6 +1,4 @@
-use std::fmt::Formatter;
 use std::hash::BuildHasherDefault;
-use std::ops::Deref;
 use std::path::{Path, PathBuf};
 
 use rustc_hash::{FxHashSet, FxHasher};
@@ -68,41 +66,3 @@ impl Workspace {
         self.open_files.contains(&file_id)
     }
 }
-
-#[derive(Debug, Clone, Eq, PartialEq, Hash)]
-pub struct Name(smol_str::SmolStr);
-
-impl Name {
-    #[inline]
-    pub fn new(name: &str) -> Self {
-        Self(smol_str::SmolStr::new(name))
-    }
-
-    pub fn as_str(&self) -> &str {
-        self.0.as_str()
-    }
-}
-
-impl Deref for Name {
-    type Target = str;
-
-    #[inline]
-    fn deref(&self) -> &Self::Target {
-        self.as_str()
-    }
-}
-
-impl<T> From<T> for Name
-where
-    T: Into<smol_str::SmolStr>,
-{
-    fn from(value: T) -> Self {
-        Self(value.into())
-    }
-}
-
-impl std::fmt::Display for Name {
-    fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
-        f.write_str(self.as_str())
-    }
-}

crates/red_knot/src/semantic.rs

@@ -11,7 +11,6 @@ use crate::files::FileId;
 use crate::module::Module;
 use crate::module::ModuleName;
 use crate::parse::parse;
-use crate::Name;
 pub(crate) use definitions::Definition;
 use definitions::{ImportDefinition, ImportFromDefinition};
 pub(crate) use flow_graph::ConstrainedDefinition;
@@ -437,7 +436,7 @@ impl SourceOrderVisitor<'_> for SemanticIndexer {
                     };
                     let def = Definition::ImportFrom(ImportFromDefinition {
                         module: module.clone(),
-                        name: Name::new(&alias.name.id),
+                        name: alias.name.id.clone(),
                         level: *level,
                     });
                     self.add_or_update_symbol_with_def(symbol_name, def);

crates/red_knot/src/semantic/definitions.rs

@@ -1,7 +1,7 @@
 use crate::ast_ids::TypedNodeKey;
 use crate::semantic::ModuleName;
-use crate::Name;
 use ruff_python_ast as ast;
+use ruff_python_ast::name::Name;
 
 // TODO storing TypedNodeKey for definitions means we have to search to find them again in the AST;
 // this is at best O(log n). If looking up definitions is a bottleneck we should look for

crates/red_knot/src/semantic/symbol_table.rs

@@ -9,11 +9,11 @@ use hashbrown::hash_map::{Keys, RawEntryMut};
 use rustc_hash::{FxHashMap, FxHasher};
 
 use ruff_index::{newtype_index, IndexVec};
+use ruff_python_ast::name::Name;
 
 use crate::ast_ids::NodeKey;
 use crate::module::ModuleName;
 use crate::semantic::{Definition, ExpressionId};
-use crate::Name;
 
 type Map<K, V> = hashbrown::HashMap<K, V, ()>;
 

crates/red_knot/src/semantic/types.rs

@@ -6,14 +6,15 @@ use crate::module::{Module, ModuleName};
 use crate::semantic::{
     resolve_global_symbol, semantic_index, GlobalSymbolId, ScopeId, ScopeKind, SymbolId,
 };
-use crate::{FxDashMap, FxIndexSet, Name};
+use crate::{FxDashMap, FxIndexSet};
 use ruff_index::{newtype_index, IndexVec};
 use ruff_python_ast as ast;
 use rustc_hash::FxHashMap;
 
 pub(crate) mod infer;
 
 pub(crate) use infer::{infer_definition_type, infer_symbol_public_type};
+use ruff_python_ast::name::Name;
 
 /// unique ID for a type
 #[derive(Copy, Clone, Debug, PartialEq, Eq, Hash)]

crates/red_knot/src/semantic/types/infer.rs

@@ -13,7 +13,7 @@ use crate::semantic::{
     resolve_global_symbol, semantic_index, ConstrainedDefinition, Definition, GlobalSymbolId,
     ImportDefinition, ImportFromDefinition,
 };
-use crate::{FileId, Name};
+use crate::FileId;
 
 // FIXME: Figure out proper dead-lock free synchronisation now that this takes `&db` instead of `&mut db`.
 /// Resolve the public-facing type for a symbol (the type seen by other scopes: other modules, or
@@ -315,7 +315,7 @@ fn infer_expr_type(db: &dyn SemanticDb, file_id: FileId, expr: &ast::Expr) -> Qu
         }
         ast::Expr::Attribute(ast::ExprAttribute { value, attr, .. }) => {
             let value_type = infer_expr_type(db, file_id, value)?;
-            let attr_name = &Name::new(&attr.id);
+            let attr_name = &attr.id;
             value_type
                 .get_member(db, attr_name)
                 .map(|ty| ty.unwrap_or(Type::Unknown))
@@ -343,6 +343,7 @@ fn infer_expr_type(db: &dyn SemanticDb, file_id: FileId, expr: &ast::Expr) -> Qu
 #[cfg(test)]
 mod tests {
 
+    use ruff_python_ast::name::Name;
     use std::path::PathBuf;
 
     use crate::db::tests::TestDb;
@@ -351,7 +352,6 @@ mod tests {
         resolve_module, set_module_search_paths, ModuleName, ModuleResolutionInputs,
     };
     use crate::semantic::{infer_symbol_public_type, resolve_global_symbol, Type};
-    use crate::Name;
 
     // TODO with virtual filesystem we shouldn't have to write files to disk for these
     // tests
@@ -476,7 +476,7 @@ mod tests {
         };
 
         let member_ty = class_id
-            .get_own_class_member(&case.db, &Name::new("f"))
+            .get_own_class_member(&case.db, &Name::new_static("f"))
             .expect("C.f to resolve");
 
         let Some(Type::Function(func_id)) = member_ty else {

crates/red_knot_python_semantic/Cargo.toml

@@ -21,7 +21,6 @@ bitflags = { workspace = true }
 indexmap = { workspace = true }
 salsa = { workspace = true }
 smallvec = { workspace = true }
-smol_str = { workspace = true }
 tracing = { workspace = true }
 rustc-hash = { workspace = true }
 hashbrown = { workspace = true }

crates/red_knot_python_semantic/src/lib.rs

@@ -1,6 +1,5 @@
 pub mod ast_node_ref;
 mod db;
-pub mod name;
 mod node_key;
 pub mod semantic_index;
 pub mod types;