Merge branch 'master' into import-cycle

* master: (32 commits)
  Fix some fine-grained cache/fswatcher problems (python#4560)
  Sync typeshed (python#4559)
  Add _cached suffix to test cases in fine-grained tests with cache (python#4558)
  Add back support for simplified fine-grained logging (python#4557)
  Type checking of class decorators (python#4544)
  Sync typeshed (python#4556)
  When loading from a fine-grained cache, use the real path, not the cached (python#4555)
  Switch all of the fine-grained debug logging to use manager.log (python#4550)
  Caching for fine-grained incremental mode (python#4483)
  Fix --warn-return-any for NotImplemented (python#4545)
  Remove myunit (python#4369)
  Store line numbers of imports in the cache metadata (python#4533)
  README.md: Fix a typo (python#4529)
  Enable generation and caching of fine-grained dependencies from normal runs (python#4526)
  Move argument parsing for the fine-grained flag into the main arg parsing code (python#4524)
  Don't warn about unrecognized options starting with 'x_' (python#4522)
  stubgen: don't append star arg when args list already has varargs appended (python#4518)
  Handle TypedDict in diff and deps (python#4510)
  Fix Options.__repr__ to not infinite recurse (python#4514)
  Fix some fine-grained incremental bugs with newly imported files (python#4502)
  ...

README.md

@@ -14,7 +14,7 @@ sure you've found a bug please search our issue trackers for a
 duplicate before filing a new issue:
 
 - [mypy tracker](https://github.com/python/mypy/issues)
-  for mypy isues
+  for mypy issues
 - [typeshed tracker](https://github.com/python/typeshed/issues)
   for issues with specific modules
 - [typing tracker](https://github.com/python/typing/issues)

mypy/build.py

@@ -52,6 +52,14 @@
 from mypy.version import __version__
 from mypy.plugin import Plugin, DefaultPlugin, ChainedPlugin
 from mypy.defaults import PYTHON3_VERSION_MIN
+from mypy.server.deps import get_dependencies
+
+
+# Switch to True to produce debug output related to fine-grained incremental
+# mode only that is useful during development. This produces only a subset of
+# output compared to --verbose output. We use a global flag to enable this so
+# that it's easy to enable this when running tests.
+DEBUG_FINE_GRAINED = False
 
 
 PYTHON_EXTENSIONS = ['.pyi', '.py']
@@ -392,6 +400,7 @@ def default_lib_path(data_dir: str,
                         ('child_modules', List[str]),  # all submodules of the given module
                         ('options', Optional[Dict[str, object]]),  # build options
                         ('dep_prios', List[int]),
+                        ('dep_lines', List[int]),
                         ('interface_hash', str),  # hash representing the public interface
                         ('version_id', str),  # mypy version for cache invalidation
                         ('ignore_all', bool),  # if errors were ignored
@@ -417,6 +426,7 @@ def cache_meta_from_dict(meta: Dict[str, Any], data_json: str) -> CacheMeta:
         meta.get('child_modules', []),
         meta.get('options'),
         meta.get('dep_prios', []),
+        meta.get('dep_lines', []),
         meta.get('interface_hash', ''),
         meta.get('version_id', sentinel),
         meta.get('ignore_all', True),
@@ -731,6 +741,17 @@ def log(self, *message: str) -> None:
                 print(file=sys.stderr)
             sys.stderr.flush()
 
+    def log_fine_grained(self, *message: str) -> None:
+        if self.options.verbosity >= 1:
+            self.log('fine-grained:', *message)
+        elif DEBUG_FINE_GRAINED:
+            # Output log in a simplified format that is quick to browse.
+            if message:
+                print(*message, file=sys.stderr)
+            else:
+                print(file=sys.stderr)
+            sys.stderr.flush()
+
     def trace(self, *message: str) -> None:
         if self.options.verbosity >= 2:
             print('TRACE:', *message, file=sys.stderr)
@@ -1039,7 +1060,8 @@ def find_cache_meta(id: str, path: str, manager: BuildManager) -> Optional[Cache
     # Ignore cache if generated by an older mypy version.
     if ((m.version_id != manager.version_id and not manager.options.skip_version_check)
             or m.options is None
-            or len(m.dependencies) != len(m.dep_prios)):
+            or len(m.dependencies) != len(m.dep_prios)
+            or len(m.dependencies) != len(m.dep_lines)):
         manager.log('Metadata abandoned for {}: new attributes are missing'.format(id))
         return None
 
@@ -1127,6 +1149,17 @@ def validate_meta(meta: Optional[CacheMeta], id: str, path: Optional[str],
     if not stat.S_ISREG(st.st_mode):
         manager.log('Metadata abandoned for {}: file {} does not exist'.format(id, path))
         return None
+
+    # When we are using a fine-grained cache, we want our initial
+    # build() to load all of the cache information and then do a
+    # fine-grained incremental update to catch anything that has
+    # changed since the cache was generated. We *don't* want to do a
+    # coarse-grained incremental rebuild, so we accept the cache
+    # metadata even if it doesn't match the source file.
+    if manager.options.use_fine_grained_cache:
+        manager.log('Using potentially stale metadata for {}'.format(id))
+        return meta
+
     size = st.st_size
     if size != meta.size:
         manager.log('Metadata abandoned for {}: file {} has different size'.format(id, path))
@@ -1156,6 +1189,7 @@ def validate_meta(meta: Optional[CacheMeta], id: str, path: Optional[str],
                 'options': (manager.options.clone_for_module(id)
                             .select_options_affecting_cache()),
                 'dep_prios': meta.dep_prios,
+                'dep_lines': meta.dep_lines,
                 'interface_hash': meta.interface_hash,
                 'version_id': manager.version_id,
                 'ignore_all': meta.ignore_all,
@@ -1183,8 +1217,9 @@ def compute_hash(text: str) -> str:
 
 
 def write_cache(id: str, path: str, tree: MypyFile,
+                serialized_fine_grained_deps: Dict[str, List[str]],
                 dependencies: List[str], suppressed: List[str],
-                child_modules: List[str], dep_prios: List[int],
+                child_modules: List[str], dep_prios: List[int], dep_lines: List[int],
                 old_interface_hash: str, source_hash: str,
                 ignore_all: bool, manager: BuildManager) -> Tuple[str, Optional[CacheMeta]]:
     """Write cache files for a module.
@@ -1201,6 +1236,7 @@ def write_cache(id: str, path: str, tree: MypyFile,
       suppressed: module IDs which were suppressed as dependencies
       child_modules: module IDs which are this package's direct submodules
       dep_prios: priorities (parallel array to dependencies)
+      dep_lines: import line locations (parallel array to dependencies)
       old_interface_hash: the hash from the previous version of the data cache file
       source_hash: the hash of the source code
       ignore_all: the ignore_all flag for this module
@@ -1221,7 +1257,9 @@ def write_cache(id: str, path: str, tree: MypyFile,
     assert os.path.dirname(meta_json) == parent
 
     # Serialize data and analyze interface
-    data = tree.serialize()
+    data = {'tree': tree.serialize(),
+            'fine_grained_deps': serialized_fine_grained_deps,
+            }
     if manager.options.debug_cache:
         data_str = json.dumps(data, indent=2, sort_keys=True)
     else:
@@ -1282,6 +1320,7 @@ def write_cache(id: str, path: str, tree: MypyFile,
             'child_modules': child_modules,
             'options': options.select_options_affecting_cache(),
             'dep_prios': dep_prios,
+            'dep_lines': dep_lines,
             'interface_hash': interface_hash,
             'version_id': manager.version_id,
             'ignore_all': ignore_all,
@@ -1523,6 +1562,8 @@ class State:
     # Whether the module has an error or any of its dependencies have one.
     transitive_error = False
 
+    fine_grained_deps = None  # type: Dict[str, Set[str]]
+
     # Type checker used for checking this file.  Use type_checker() for
     # access and to construct this on demand.
     _type_checker = None  # type: Optional[TypeChecker]
@@ -1551,6 +1592,7 @@ def __init__(self,
         self.id = id or '__main__'
         self.options = manager.options.clone_for_module(self.id)
         self._type_checker = None
+        self.fine_grained_deps = {}
         if not path and source is None:
             assert id is not None
             file_id = id
@@ -1626,8 +1668,10 @@ def __init__(self,
             assert len(self.meta.dependencies) == len(self.meta.dep_prios)
             self.priorities = {id: pri
                                for id, pri in zip(self.meta.dependencies, self.meta.dep_prios)}
+            assert len(self.meta.dependencies) == len(self.meta.dep_lines)
+            self.dep_line_map = {id: line
+                                 for id, line in zip(self.meta.dependencies, self.meta.dep_lines)}
             self.child_modules = set(self.meta.child_modules)
-            self.dep_line_map = {}
         else:
             # Parse the file (and then some) to get the dependencies.
             self.parse_file()
@@ -1734,7 +1778,9 @@ def load_tree(self) -> None:
         with open(self.meta.data_json) as f:
             data = json.load(f)
         # TODO: Assert data file wasn't changed.
-        self.tree = MypyFile.deserialize(data)
+        self.tree = MypyFile.deserialize(data['tree'])
+        self.fine_grained_deps = {k: set(v) for k, v in data['fine_grained_deps'].items()}
+
         self.manager.modules[self.id] = self.tree
         self.manager.add_stats(fresh_trees=1)
 
@@ -1977,6 +2023,19 @@ def _patch_indirect_dependencies(self,
             elif dep not in self.suppressed and dep in self.manager.missing_modules:
                 self.suppressed.append(dep)
 
+    def compute_fine_grained_deps(self) -> None:
+        assert self.tree is not None
+        if '/typeshed/' in self.xpath or self.xpath.startswith('typeshed/'):
+            # We don't track changes to typeshed -- the assumption is that they are only changed
+            # as part of mypy updates, which will invalidate everything anyway.
+            #
+            # TODO: Not a reliable test, as we could have a package named typeshed.
+            # TODO: Consider relaxing this -- maybe allow some typeshed changes to be tracked.
+            return
+        self.fine_grained_deps = get_dependencies(target=self.tree,
+                                                  type_map=self.type_map(),
+                                                  python_version=self.options.python_version)
+
     def valid_references(self) -> Set[str]:
         assert self.ancestors is not None
         valid_refs = set(self.dependencies + self.suppressed + self.ancestors)
@@ -2001,10 +2060,12 @@ def write_cache(self) -> None:
             self.mark_interface_stale(on_errors=True)
             return
         dep_prios = self.dependency_priorities()
+        dep_lines = self.dependency_lines()
         new_interface_hash, self.meta = write_cache(
             self.id, self.path, self.tree,
+            {k: list(v) for k, v in self.fine_grained_deps.items()},
             list(self.dependencies), list(self.suppressed), list(self.child_modules),
-            dep_prios, self.interface_hash, self.source_hash, self.ignore_all,
+            dep_prios, dep_lines, self.interface_hash, self.source_hash, self.ignore_all,
             self.manager)
         if new_interface_hash == self.interface_hash:
             self.manager.log("Cached module {} has same interface".format(self.id))
@@ -2016,6 +2077,9 @@ def write_cache(self) -> None:
     def dependency_priorities(self) -> List[int]:
         return [self.priorities.get(dep, PRI_HIGH) for dep in self.dependencies]
 
+    def dependency_lines(self) -> List[int]:
+        return [self.dep_line_map.get(dep, 1) for dep in self.dependencies]
+
     def generate_unused_ignore_notes(self) -> None:
         if self.options.warn_unused_ignores:
             self.manager.errors.generate_unused_ignore_notes(self.xpath)
@@ -2348,6 +2412,14 @@ def process_graph(graph: Graph, manager: BuildManager) -> None:
                 manager.log("Processing SCC of size %d (%s) as %s" % (size, scc_str, fresh_msg))
             process_stale_scc(graph, scc, manager)
 
+    # If we are running in fine-grained incremental mode with caching,
+    # we always process fresh SCCs so that we have all of the symbol
+    # tables and fine-grained dependencies available.
+    if manager.options.use_fine_grained_cache:
+        for prev_scc in fresh_scc_queue:
+            process_fresh_scc(graph, prev_scc, manager)
+        fresh_scc_queue = []
+
     sccs_left = len(fresh_scc_queue)
     nodes_left = sum(len(scc) for scc in fresh_scc_queue)
     manager.add_stats(sccs_left=sccs_left, nodes_left=nodes_left)
@@ -2534,6 +2606,8 @@ def process_stale_scc(graph: Graph, scc: List[str], manager: BuildManager) -> No
             graph[id].transitive_error = True
     for id in stale:
         graph[id].finish_passes()
+        if manager.options.cache_fine_grained or manager.options.fine_grained_incremental:
+            graph[id].compute_fine_grained_deps()
         graph[id].generate_unused_ignore_notes()
         manager.flush_errors(manager.errors.file_messages(graph[id].xpath), False)
         graph[id].write_cache()

mypy/checker.py

@@ -40,7 +40,7 @@
 from mypy.sametypes import is_same_type, is_same_types
 from mypy.messages import MessageBuilder, make_inferred_type_note
 import mypy.checkexpr
-from mypy.checkmember import map_type_from_supertype, bind_self, erase_to_bound
+from mypy.checkmember import map_type_from_supertype, bind_self, erase_to_bound, type_object_type
 from mypy import messages
 from mypy.subtypes import (
     is_subtype, is_equivalent, is_proper_subtype, is_more_precise,
@@ -59,6 +59,7 @@
 from mypy.meet import is_overlapping_types
 from mypy.options import Options
 from mypy.plugin import Plugin, CheckerPluginInterface
+from mypy.sharedparse import BINARY_MAGIC_METHODS
 
 from mypy import experiments
 
@@ -1254,6 +1255,29 @@ def visit_class_def(self, defn: ClassDef) -> None:
                 # Otherwise we've already found errors; more errors are not useful
                 self.check_multiple_inheritance(typ)
 
+            if defn.decorators:
+                sig = type_object_type(defn.info, self.named_type)
+                # Decorators are applied in reverse order.
+                for decorator in reversed(defn.decorators):
+                    if (isinstance(decorator, CallExpr)
+                            and isinstance(decorator.analyzed, PromoteExpr)):
+                        # _promote is a special type checking related construct.
+                        continue
+
+                    dec = self.expr_checker.accept(decorator)
+                    temp = self.temp_node(sig)
+                    fullname = None
+                    if isinstance(decorator, RefExpr):
+                        fullname = decorator.fullname
+
+                    # TODO: Figure out how to have clearer error messages.
+                    # (e.g. "class decorator must be a function that accepts a type."
+                    sig, _ = self.expr_checker.check_call(dec, [temp],
+                                                          [nodes.ARG_POS], defn,
+                                                          callable_name=fullname)
+                # TODO: Apply the sig to the actual TypeInfo so we can handle decorators
+                # that completely swap out the type.  (e.g. Callable[[Type[A]], Type[B]])
+
     def check_protocol_variance(self, defn: ClassDef) -> None:
         """Check that protocol definition is compatible with declared
         variances of type variables.
@@ -1940,13 +1964,13 @@ def infer_variable_type(self, name: Var, lvalue: Lvalue,
             # partial type which will be made more specific later. A partial type
             # gets generated in assignment like 'x = []' where item type is not known.
             if not self.infer_partial_type(name, lvalue, init_type):
-                self.fail(messages.NEED_ANNOTATION_FOR_VAR, context)
+                self.msg.need_annotation_for_var(name, context)
                 self.set_inference_error_fallback_type(name, lvalue, init_type, context)
         elif (isinstance(lvalue, MemberExpr) and self.inferred_attribute_types is not None
               and lvalue.def_var and lvalue.def_var in self.inferred_attribute_types
               and not is_same_type(self.inferred_attribute_types[lvalue.def_var], init_type)):
             # Multiple, inconsistent types inferred for an attribute.
-            self.fail(messages.NEED_ANNOTATION_FOR_VAR, context)
+            self.msg.need_annotation_for_var(name, context)
             name.type = AnyType(TypeOfAny.from_error)
         else:
             # Infer type of the target.
@@ -2179,8 +2203,11 @@ def check_return_stmt(self, s: ReturnStmt) -> None:
                 if isinstance(typ, AnyType):
                     # (Unless you asked to be warned in that case, and the
                     # function is not declared to return Any)
-                    if (self.options.warn_return_any and not self.current_node_deferred and
-                            not is_proper_subtype(AnyType(TypeOfAny.special_form), return_type)):
+                    if (self.options.warn_return_any
+                        and not self.current_node_deferred
+                        and not is_proper_subtype(AnyType(TypeOfAny.special_form), return_type)
+                        and not (defn.name() in BINARY_MAGIC_METHODS and
+                                 is_literal_not_implemented(s.expr))):
                         self.msg.incorrectly_returning_any(return_type, s)
                     return
 
@@ -3101,7 +3128,7 @@ def enter_partial_types(self) -> Iterator[None]:
                     var.type = NoneTyp()
                 else:
                     if var not in self.partial_reported:
-                        self.msg.fail(messages.NEED_ANNOTATION_FOR_VAR, context)
+                        self.msg.need_annotation_for_var(var, context)
                         self.partial_reported.add(var)
                     var.type = AnyType(TypeOfAny.from_error)
 
@@ -3232,6 +3259,10 @@ def remove_optional(typ: Type) -> Type:
         return typ
 
 
+def is_literal_not_implemented(n: Expression) -> bool:
+    return isinstance(n, NameExpr) and n.fullname == 'builtins.NotImplemented'
+
+
 def builtin_item_type(tp: Type) -> Optional[Type]:
     """Get the item type of a builtin container.
 

mypy/checkexpr.py

@@ -145,7 +145,7 @@ def analyze_ref_expr(self, e: RefExpr, lvalue: bool = False) -> Type:
                     partial_types = self.chk.find_partial_types(node)
                     if partial_types is not None and not self.chk.current_node_deferred:
                         context = partial_types[node]
-                        self.msg.fail(messages.NEED_ANNOTATION_FOR_VAR, context)
+                        self.msg.need_annotation_for_var(node, context)
                     result = AnyType(TypeOfAny.special_form)
         elif isinstance(node, FuncDef):
             # Reference to a global function.

mypy/checkmember.py

@@ -366,7 +366,7 @@ def freeze_type_vars(member_type: Type) -> None:
 
 
 def handle_partial_attribute_type(typ: PartialType, is_lvalue: bool, msg: MessageBuilder,
-                                  context: Context) -> Type:
+                                  node: SymbolNode) -> Type:
     if typ.type is None:
         # 'None' partial type. It has a well-defined type -- 'None'.
         # In an lvalue context we want to preserver the knowledge of
@@ -375,7 +375,7 @@ def handle_partial_attribute_type(typ: PartialType, is_lvalue: bool, msg: Messag
             return NoneTyp()
         return typ
     else:
-        msg.fail(messages.NEED_ANNOTATION_FOR_VAR, context)
+        msg.need_annotation_for_var(node, node)
         return AnyType(TypeOfAny.from_error)