Start moving away from named_type callback architecture

Author: ilevkivskyi

mypy/build.py

@@ -143,7 +143,6 @@
 
 from mypy import errorcodes as codes
 from mypy.config_parser import get_config_module_names, parse_mypy_comments
-from mypy.fixer_state import fixer_state
 from mypy.fixup import NodeFixer
 from mypy.freetree import free_tree
 from mypy.fscache import FileSystemCache
@@ -159,6 +158,7 @@
     SearchPaths,
     compute_search_paths,
 )
+from mypy.modules_state import modules_state
 from mypy.nodes import Expression
 from mypy.options import Options
 from mypy.parse import load_from_raw, parse
@@ -816,7 +816,8 @@ def __init__(
         # Share same modules dictionary with the global fixer state.
         # We need to set allow_missing when doing a fine-grained cache
         # load because we need to gracefully handle missing modules.
-        fixer_state.node_fixer = NodeFixer(self.modules, self.options.use_fine_grained_cache)
+        modules_state.modules = self.modules
+        modules_state.node_fixer = NodeFixer(self.modules, self.options.use_fine_grained_cache)
         self.import_map: dict[str, set[str]] = {}
         self.missing_modules: dict[str, int] = {}
         self.fg_deps_meta: dict[str, FgDepMeta] = {}
@@ -2816,9 +2817,9 @@ def load_tree(self, temporary: bool = False) -> None:
     def fix_cross_refs(self) -> None:
         assert self.tree is not None, "Internal error: method must be called on parsed file only"
         # Do initial lightweight pass fixing TypeInfos and module cross-references.
-        assert fixer_state.node_fixer is not None
-        fixer_state.node_fixer.visit_symbol_table(self.tree.names)
-        type_fixer = fixer_state.node_fixer.type_fixer
+        assert modules_state.node_fixer is not None
+        modules_state.node_fixer.visit_symbol_table(self.tree.names)
+        type_fixer = modules_state.node_fixer.type_fixer
         # Eagerly fix shared instances, before they are used by named_type() calls.
         if instance_cache.str_type is not None:
             instance_cache.str_type.accept(type_fixer)

mypy/checker.py

@@ -2702,7 +2702,7 @@ def visit_class_def(self, defn: ClassDef) -> None:
                 self.check_final_deletable(typ)
 
             if defn.decorators:
-                sig: Type = type_object_type(defn.info, self.named_type)
+                sig: Type = type_object_type(defn.info)
                 # Decorators are applied in reverse order.
                 for decorator in reversed(defn.decorators):
                     if isinstance(decorator, CallExpr) and isinstance(

mypy/checkexpr.py

@@ -427,7 +427,7 @@ def analyze_static_reference(
                 # We special case NoneType, because its stub definition is not related to None.
                 return TypeType(NoneType())
             else:
-                return type_object_type(node, self.named_type)
+                return type_object_type(node)
         elif isinstance(node, TypeAlias):
             # Something that refers to a type alias appears in runtime context.
             # Note that we suppress bogus errors for alias redefinitions,
@@ -1908,7 +1908,7 @@ def analyze_type_type_callee(self, item: ProperType, context: Context) -> Type:
         if isinstance(item, AnyType):
             return AnyType(TypeOfAny.from_another_any, source_any=item)
         if isinstance(item, Instance):
-            res = type_object_type(item.type, self.named_type)
+            res = type_object_type(item.type)
             if isinstance(res, CallableType):
                 res = res.copy_modified(from_type_type=True)
             expanded = expand_type_by_instance(res, item)
@@ -4076,6 +4076,44 @@ def check_method_call(
             object_type=base_type,
         )
 
+    def lookup_operator(self, op_name: str, base_type: Type, context: Context) -> Type | None:
+        """Looks up the given operator and returns the corresponding type,
+        if it exists."""
+
+        # This check is an important performance optimization.
+        if not has_operator(base_type, op_name):
+            return None
+
+        with self.msg.filter_errors() as w:
+            member = analyze_member_access(
+                name=op_name,
+                typ=base_type,
+                is_lvalue=False,
+                is_super=False,
+                is_operator=True,
+                original_type=base_type,
+                context=context,
+                chk=self.chk,
+                in_literal_context=self.is_literal_context(),
+            )
+            return None if w.has_new_errors() else member
+
+    def lookup_definer(self, typ: Instance, attr_name: str) -> str | None:
+        """Returns the name of the class that contains the actual definition of attr_name.
+
+        So if class A defines foo and class B subclasses A, running
+        `get_class_defined_in(B, "foo")` would return the full name of A.
+
+        However, if B were to override and redefine foo, that method call would
+        return the full name of B instead.
+
+        If the attr name is not present in the given class or its MRO, returns None.
+        """
+        for cls in typ.type.mro:
+            if cls.names.get(attr_name):
+                return cls.fullname
+        return None
+
     def check_op_reversible(
         self,
         op_name: str,
@@ -4085,48 +4123,10 @@ def check_op_reversible(
         right_expr: Expression,
         context: Context,
     ) -> tuple[Type, Type]:
-        def lookup_operator(op_name: str, base_type: Type) -> Type | None:
-            """Looks up the given operator and returns the corresponding type,
-            if it exists."""
-
-            # This check is an important performance optimization.
-            if not has_operator(base_type, op_name, self.named_type):
-                return None
-
-            with self.msg.filter_errors() as w:
-                member = analyze_member_access(
-                    name=op_name,
-                    typ=base_type,
-                    is_lvalue=False,
-                    is_super=False,
-                    is_operator=True,
-                    original_type=base_type,
-                    context=context,
-                    chk=self.chk,
-                    in_literal_context=self.is_literal_context(),
-                )
-                return None if w.has_new_errors() else member
-
-        def lookup_definer(typ: Instance, attr_name: str) -> str | None:
-            """Returns the name of the class that contains the actual definition of attr_name.
-
-            So if class A defines foo and class B subclasses A, running
-            'get_class_defined_in(B, "foo")` would return the full name of A.
-
-            However, if B were to override and redefine foo, that method call would
-            return the full name of B instead.
-
-            If the attr name is not present in the given class or its MRO, returns None.
-            """
-            for cls in typ.type.mro:
-                if cls.names.get(attr_name):
-                    return cls.fullname
-            return None
-
         left_type = get_proper_type(left_type)
         right_type = get_proper_type(right_type)
 
-        # If either the LHS or the RHS are Any, we can't really concluding anything
+        # If either the LHS or the RHS are Any, we can't really conclude anything
         # about the operation since the Any type may or may not define an
         # __op__ or __rop__ method. So, we punt and return Any instead.
 
@@ -4142,8 +4142,8 @@ def lookup_definer(typ: Instance, attr_name: str) -> str | None:
 
         rev_op_name = operators.reverse_op_methods[op_name]
 
-        left_op = lookup_operator(op_name, left_type)
-        right_op = lookup_operator(rev_op_name, right_type)
+        left_op = self.lookup_operator(op_name, left_type, context)
+        right_op = self.lookup_operator(rev_op_name, right_type, context)
 
         # STEP 2a:
         # We figure out in which order Python will call the operator methods. As it
@@ -4168,7 +4168,8 @@ def lookup_definer(typ: Instance, attr_name: str) -> str | None:
                 #    B: right's __rop__ method is different from left's __op__ method
                 not (isinstance(left_type, Instance) and isinstance(right_type, Instance))
                 or (
-                    lookup_definer(left_type, op_name) != lookup_definer(right_type, rev_op_name)
+                    self.lookup_definer(left_type, op_name)
+                    != self.lookup_definer(right_type, rev_op_name)
                     and (
                         left_type.type.alt_promote is None
                         or left_type.type.alt_promote.type is not right_type.type
@@ -4931,10 +4932,10 @@ def visit_type_application(self, tapp: TypeApplication) -> Type:
             )
             item = get_proper_type(item)
             if isinstance(item, Instance):
-                tp = type_object_type(item.type, self.named_type)
+                tp = type_object_type(item.type)
                 return self.apply_type_arguments_to_callable(tp, item.args, tapp)
             elif isinstance(item, TupleType) and item.partial_fallback.type.is_named_tuple:
-                tp = type_object_type(item.partial_fallback.type, self.named_type)
+                tp = type_object_type(item.partial_fallback.type)
                 return self.apply_type_arguments_to_callable(tp, item.partial_fallback.args, tapp)
             elif isinstance(item, TypedDictType):
                 return self.typeddict_callable_from_context(item)
@@ -5003,7 +5004,7 @@ class LongName(Generic[T]): ...
         if isinstance(item, Instance):
             # Normally we get a callable type (or overloaded) with .is_type_obj() true
             # representing the class's constructor
-            tp = type_object_type(item.type, self.named_type)
+            tp = type_object_type(item.type)
             if alias.no_args:
                 return tp
             return self.apply_type_arguments_to_callable(tp, item.args, ctx)
@@ -5013,7 +5014,7 @@ class LongName(Generic[T]): ...
             # Tuple[str, int]() fails at runtime, only named tuples and subclasses work.
             tuple_fallback(item).type.fullname != "builtins.tuple"
         ):
-            return type_object_type(tuple_fallback(item).type, self.named_type)
+            return type_object_type(tuple_fallback(item).type)
         elif isinstance(item, TypedDictType):
             return self.typeddict_callable_from_context(item)
         elif isinstance(item, NoneType):

mypy/checkmember.py

@@ -13,9 +13,11 @@
     expand_type_by_instance,
     freshen_all_functions_type_vars,
 )
+from mypy.lookup import lookup_stdlib_typeinfo
 from mypy.maptype import map_instance_to_supertype
 from mypy.meet import is_overlapping_types
 from mypy.messages import MessageBuilder
+from mypy.modules_state import modules_state
 from mypy.nodes import (
     ARG_POS,
     ARG_STAR,
@@ -74,6 +76,7 @@
     UninhabitedType,
     UnionType,
     get_proper_type,
+    instance_cache,
 )
 
 
@@ -1525,7 +1528,7 @@ def bind_self_fast(method: F, original_type: Type | None = None) -> F:
     )
 
 
-def has_operator(typ: Type, op_method: str, named_type: Callable[[str], Instance]) -> bool:
+def has_operator(typ: Type, op_method: str) -> bool:
     """Does type have operator with the given name?
 
     Note: this follows the rules for operator access, in particular:
@@ -1544,7 +1547,7 @@ def has_operator(typ: Type, op_method: str, named_type: Callable[[str], Instance
     if isinstance(typ, AnyType):
         return True
     if isinstance(typ, UnionType):
-        return all(has_operator(x, op_method, named_type) for x in typ.relevant_items())
+        return all(has_operator(x, op_method) for x in typ.relevant_items())
     if isinstance(typ, FunctionLike) and typ.is_type_obj():
         return typ.fallback.type.has_readable_member(op_method)
     if isinstance(typ, TypeType):
@@ -1555,27 +1558,33 @@ def has_operator(typ: Type, op_method: str, named_type: Callable[[str], Instance
         if isinstance(item, TypeVarType):
             item = item.values_or_bound()
         if isinstance(item, UnionType):
-            return all(meta_has_operator(x, op_method, named_type) for x in item.relevant_items())
-        return meta_has_operator(item, op_method, named_type)
-    return instance_fallback(typ, named_type).type.has_readable_member(op_method)
+            return all(meta_has_operator(x, op_method) for x in item.relevant_items())
+        return meta_has_operator(item, op_method)
+    return instance_fallback(typ).type.has_readable_member(op_method)
 
 
-def instance_fallback(typ: ProperType, named_type: Callable[[str], Instance]) -> Instance:
+def instance_fallback(typ: ProperType) -> Instance:
     if isinstance(typ, Instance):
         return typ
     if isinstance(typ, TupleType):
         return tuple_fallback(typ)
     if isinstance(typ, (LiteralType, TypedDictType)):
         return typ.fallback
-    return named_type("builtins.object")
+    if instance_cache.object_type is None:
+        object_typeinfo = lookup_stdlib_typeinfo("builtins.object", modules_state.modules)
+        instance_cache.object_type = Instance(object_typeinfo, [])
+    return instance_cache.object_type
 
 
-def meta_has_operator(item: Type, op_method: str, named_type: Callable[[str], Instance]) -> bool:
+def meta_has_operator(item: Type, op_method: str) -> bool:
     item = get_proper_type(item)
     if isinstance(item, AnyType):
         return True
-    item = instance_fallback(item, named_type)
-    meta = item.type.metaclass_type or named_type("builtins.type")
+    item = instance_fallback(item)
+    meta = item.type.metaclass_type
+    if meta is None:
+        type_type = lookup_stdlib_typeinfo("builtins.type", modules_state.modules)
+        meta = Instance(type_type, [])
     return meta.type.has_readable_member(op_method)
 
 

mypy/lookup.py

@@ -66,3 +66,15 @@ def lookup_fully_qualified(
                 assert node, f"Cannot find {name}"
             return None
         names = node.names
+
+
+def lookup_stdlib_typeinfo(fullname: str, modules: dict[str, MypyFile]) -> TypeInfo:
+    """Find TypeInfo for a standard library type.
+
+    This fast path assumes that the type exists at module top-level, use this
+    function only for common types like `builtins.object` or `typing.Iterable`.
+    """
+    module, name = fullname.rsplit(".", maxsplit=1)
+    sym = modules[module].names[name]
+    assert isinstance(sym.node, TypeInfo)
+    return sym.node

mypy/messages.py

@@ -68,6 +68,7 @@
     IS_VAR,
     find_member,
     get_member_flags,
+    get_protocol_member,
     is_same_type,
     is_subtype,
 )
@@ -3110,7 +3111,7 @@ def get_conflict_protocol_types(
             continue
         supertype = find_member(member, right, left)
         assert supertype is not None
-        subtype = mypy.typeops.get_protocol_member(left, member, class_obj)
+        subtype = get_protocol_member(left, member, class_obj)
         if not subtype:
             continue
         is_compat = is_subtype(subtype, supertype, ignore_pos_arg_names=True, options=options)
@@ -3126,7 +3127,7 @@ def get_conflict_protocol_types(
                 different_setter = True
             supertype = set_supertype
         if IS_EXPLICIT_SETTER in get_member_flags(member, left):
-            set_subtype = mypy.typeops.get_protocol_member(left, member, class_obj, is_lvalue=True)
+            set_subtype = get_protocol_member(left, member, class_obj, is_lvalue=True)
             if set_subtype and not is_same_type(set_subtype, subtype):
                 different_setter = True
             subtype = set_subtype

mypy/fixer_state.py mypy/modules_state.pymypy/fixer_state.py renamed to mypy/modules_state.py

@@ -4,6 +4,7 @@
 
 if TYPE_CHECKING:
     from mypy.fixup import NodeFixer
+    from mypy.nodes import MypyFile
 
 # This is global mutable state. Don't add anything here unless there's a very
 # good reason. This exists as a separate file to avoid method-level import in
@@ -13,6 +14,7 @@
 class FixerState:
     def __init__(self) -> None:
         self.node_fixer: NodeFixer | None = None
+        self.modules: dict[str, MypyFile] = {}
 
 
-fixer_state: Final = FixerState()
+modules_state: Final = FixerState()

mypy/nodes.py

@@ -68,7 +68,7 @@
     write_str_opt_list,
     write_tag,
 )
-from mypy.fixer_state import fixer_state
+from mypy.modules_state import modules_state
 from mypy.options import Options
 from mypy.util import is_sunder, is_typeshed_file, short_type
 from mypy.visitor import ExpressionVisitor, NodeVisitor, StatementVisitor
@@ -4819,7 +4819,7 @@ def type(self) -> mypy.types.Type | None:
     @property
     def node(self) -> SymbolNode | None:
         if self.unfixed:
-            node_fixer = fixer_state.node_fixer
+            node_fixer = modules_state.node_fixer
             assert node_fixer is not None
             if self.cross_ref is not None:
                 node_fixer.resolve_cross_ref(self)

mypy/plugins/attrs.py

@@ -734,15 +734,15 @@ def _parse_converter(
         ):
             converter_type = converter_expr.node.type
         elif isinstance(converter_expr.node, TypeInfo):
-            converter_type = type_object_type(converter_expr.node, ctx.api.named_type)
+            converter_type = type_object_type(converter_expr.node)
     elif (
         isinstance(converter_expr, IndexExpr)
         and isinstance(converter_expr.analyzed, TypeApplication)
         and isinstance(converter_expr.base, RefExpr)
         and isinstance(converter_expr.base.node, TypeInfo)
     ):
         # The converter is a generic type.
-        converter_type = type_object_type(converter_expr.base.node, ctx.api.named_type)
+        converter_type = type_object_type(converter_expr.base.node)
         if isinstance(converter_type, CallableType):
             converter_type = apply_generic_arguments(
                 converter_type,