New semantic analyzer: Report undefined names in function types

mypy/newsemanal/semanal.py

@@ -541,7 +541,11 @@ def _visit_func_def(self, defn: FuncDef) -> None:
                 # Signature must be analyzed in the surrounding scope so that
                 # class-level imported names and type variables are in scope.
                 analyzer = self.type_analyzer()
-                defn.type = analyzer.visit_callable_type(defn.type, nested=False)
+                tag = self.track_incomplete_refs()
+                result = analyzer.visit_callable_type(defn.type, nested=False)
+                if self.found_incomplete_ref(tag):
+                    return
+                defn.type = result
                 self.add_type_alias_deps(analyzer.aliases_used)
                 self.check_function_signature(defn)
                 if isinstance(defn, FuncDef):

test-data/unit/check-newsemanal.test

@@ -1702,3 +1702,7 @@ from typing import Tuple
 c: C
 class C(Tuple[int, str]):
     def __init__(self) -> None: pass
+
+[case testNewAnalyzerFunctionError]
+def f(x: asdf) -> None:  # E: Name 'asdf' is not defined
+    pass