Fix self binding and improve line number diagnostics

python · JelleZijlstra · Feb 17, 2022 · Jan 20, 2022 · Jan 20, 2022 · Jan 20, 2022
commit 2119c3d2db0cf42400dc9ab1996a8a1ff3e3a131
diff --git a/mypy/semanal.py b/mypy/semanal.py
@@ -48,6 +48,7 @@
   reduce memory use).
 """
 
+import copy
 from contextlib import contextmanager
 
 from typing import (
@@ -4788,10 +4789,6 @@ def add_imported_symbol(self,
         assert not module_hidden or not module_public
 
         symbol_node: Optional[SymbolNode] = node.node
-        # I promise this type checks; I'm just making mypyc issues go away.
-        # mypyc is absolutely convinced that `symbol_node` narrows to a Var in the following,
-        # when it can also be a FuncBase.
-        symbol_node_any: Any = cast(Any, symbol_node)
         if self.is_class_scope() and isinstance(symbol_node, (FuncBase, Var)):
             # We construct a new node to represent this symbol and set its `info` attribute
             # to `self.type`. Note that imports inside class scope do not produce methods, so
@@ -4802,12 +4799,19 @@ def add_imported_symbol(self,
                 # constructed Var, so check for possible redefinitions here.
                 existing is not None
                 and isinstance(existing.node, Var)
-                and existing.type == symbol_node_any.type
+                and existing.type == symbol_node.type
             ):
                 symbol_node = existing.node
             else:
-                symbol_node = Var(symbol_node_any.name, symbol_node_any.type)
+                if isinstance(symbol_node, Var):
+                    symbol_node = Var(symbol_node.name, symbol_node.type)
+                elif isinstance(symbol_node, FuncBase):
+                    symbol_node = copy.copy(symbol_node)
+                else:
+                    assert False
                 assert self.type is not None
+                symbol_node.line = context.line
+                symbol_node.column = context.column
                 symbol_node.info = self.type
                 symbol_node._fullname = self.qualified_name(name)
 

diff --git a/test-data/unit/check-classes.test b/test-data/unit/check-classes.test
@@ -7140,7 +7140,8 @@ class Foo:
     from mod import foo
 
 reveal_type(Foo.foo)  # N: Revealed type is "def (x: builtins.int, y: builtins.int) -> builtins.int"
-reveal_type(Foo().foo)  # N: Revealed type is "def (x: builtins.int, y: builtins.int) -> builtins.int"
+reveal_type(Foo().foo)  # E: Invalid self argument "Foo" to attribute function "foo" with type "Callable[[int, int], int]" \
+                        # N: Revealed type is "def (y: builtins.int) -> builtins.int"
 [file mod.py]
 def foo(x: int, y: int) -> int: ...
 
@@ -7195,7 +7196,8 @@ class Foo:
         from mod import baz
 
 reveal_type(Foo.Bar.baz)  # N: Revealed type is "def (x: builtins.int) -> builtins.int"
-reveal_type(Foo.Bar().baz)  # N: Revealed type is "def (x: builtins.int) -> builtins.int"
+reveal_type(Foo.Bar().baz)  # E: Invalid self argument "Bar" to attribute function "baz" with type "Callable[[int], int]" \
+                            # N: Revealed type is "def () -> builtins.int"
 [file mod.py]
 def baz(x: int) -> int: ...
 
@@ -7219,10 +7221,10 @@ def foo(x: int, y: int) -> int: ...
 [case testClassScopeImportVarious]
 class Foo:
     from mod1 import foo
-    from mod2 import foo  # E: Name "foo" already defined (possibly by an import)
+    from mod2 import foo  # E: Name "foo" already defined on line 2
 
     from mod1 import meth1
-    def meth1(self, a: str) -> str: ...  # E: Name "meth1" already defined (possibly by an import)
+    def meth1(self, a: str) -> str: ...  # E: Name "meth1" already defined on line 5
 
     def meth2(self, a: str) -> str: ...
     from mod1 import meth2  # E: Name "meth2" already defined on line 8