Fix crashes and fails in forward references

mypy/build.py

@@ -491,7 +491,7 @@ def __init__(self, data_dir: str,
         self.semantic_analyzer = SemanticAnalyzer(self.modules, self.missing_modules,
                                                   lib_path, self.errors, self.plugin)
         self.modules = self.semantic_analyzer.modules
-        self.semantic_analyzer_pass3 = ThirdPass(self.modules, self.errors)
+        self.semantic_analyzer_pass3 = ThirdPass(self.modules, self.errors, self.semantic_analyzer)
         self.all_types = {}  # type: Dict[Expression, Type]
         self.indirection_detector = TypeIndirectionVisitor()
         self.stale_modules = set()  # type: Set[str]
@@ -1722,10 +1722,13 @@ def semantic_analysis(self) -> None:
 
     def semantic_analysis_pass_three(self) -> None:
         assert self.tree is not None, "Internal error: method must be called on parsed file only"
+        patches = []  # type: List[Callable[[], None]]
         with self.wrap_context():
-            self.manager.semantic_analyzer_pass3.visit_file(self.tree, self.xpath, self.options)
+            self.manager.semantic_analyzer_pass3.visit_file(self.tree, self.xpath,
+                                                            self.options, patches)
             if self.options.dump_type_stats:
                 dump_type_stats(self.tree, self.xpath)
+        self.patches = patches + self.patches
 
     def semantic_analysis_apply_patches(self) -> None:
         for patch_func in self.patches:

mypy/indirection.py

@@ -101,3 +101,6 @@ def visit_ellipsis_type(self, t: types.EllipsisType) -> Set[str]:
 
     def visit_type_type(self, t: types.TypeType) -> Set[str]:
         return self._visit(t.item)
+
+    def visit_forwardref_type(self, t: types.ForwardRef) -> Set[str]:
+        return self._visit(t.link)

mypy/messages.py

@@ -20,7 +20,7 @@
 from mypy.types import (
     Type, CallableType, Instance, TypeVarType, TupleType, TypedDictType,
     UnionType, NoneTyp, AnyType, Overloaded, FunctionLike, DeletedType, TypeType,
-    UninhabitedType, TypeOfAny
+    UninhabitedType, TypeOfAny, ForwardRef, UnboundType
 )
 from mypy.nodes import (
     TypeInfo, Context, MypyFile, op_methods, FuncDef, reverse_type_aliases,
@@ -194,7 +194,7 @@ def quote_type_string(self, type_string: str) -> str:
         """Quotes a type representation for use in messages."""
         no_quote_regex = r'^<(tuple|union): \d+ items>$'
         if (type_string in ['Module', 'overloaded function', '<nothing>', '<deleted>']
-                or re.match(no_quote_regex, type_string) is not None):
+                or re.match(no_quote_regex, type_string) is not None or type_string.endswith('?')):
             # Messages are easier to read if these aren't quoted.  We use a
             # regex to match strings with variable contents.
             return type_string
@@ -309,6 +309,8 @@ def format_bare(self, typ: Type, verbosity: int = 0) -> str:
                 return '<nothing>'
         elif isinstance(typ, TypeType):
             return 'Type[{}]'.format(self.format_bare(typ.item, verbosity))
+        elif isinstance(typ, ForwardRef):  # may appear in semanal.py
+            return self.format_bare(typ.link, verbosity)
         elif isinstance(typ, FunctionLike):
             func = typ
             if func.is_type_obj():
@@ -350,6 +352,8 @@ def format_bare(self, typ: Type, verbosity: int = 0) -> str:
                 # function types may result in long and difficult-to-read
                 # error messages.
                 return 'overloaded function'
+        elif isinstance(typ, UnboundType):
+            return str(typ)
         elif typ is None:
             raise RuntimeError('Type is None')
         else:

mypy/nodes.py

@@ -1976,6 +1976,12 @@ class is generic then it will be a type constructor of higher kind.
     # Is this a newtype type?
     is_newtype = False
 
+    # If during analysis of ClassDef associated with this TypeInfo a syntethic
+    # type (NamedTuple or TypedDict) was generated, store the corresponding
+    # TypeInfo here. (This attribute does not need to be serialized, it is only
+    # needed during the semantic passes.)
+    replaced = None  # type: TypeInfo
+
     FLAGS = [
         'is_abstract', 'is_enum', 'fallback_to_any', 'is_named_tuple',
         'is_newtype', 'is_protocol', 'runtime_protocol'

mypy/server/deps.py

@@ -11,7 +11,7 @@
 from mypy.types import (
     Type, Instance, AnyType, NoneTyp, TypeVisitor, CallableType, DeletedType, PartialType,
     TupleType, TypeType, TypeVarType, TypedDictType, UnboundType, UninhabitedType, UnionType,
-    FunctionLike
+    FunctionLike, ForwardRef
 )
 from mypy.server.trigger import make_trigger
 
@@ -212,6 +212,9 @@ def visit_type_type(self, typ: TypeType) -> List[str]:
         # TODO: replace with actual implementation
         return []
 
+    def visit_forwardref_type(self, typ: ForwardRef) -> List[str]:
+        return get_type_dependencies(typ.link)
+
     def visit_type_var(self, typ: TypeVarType) -> List[str]:
         # TODO: replace with actual implementation
         return []