implement import-untyped-stubs-available

Author: wyattscarpenter

docs/source/running_mypy.rst

@@ -397,7 +397,9 @@ This is slower than explicitly installing stubs, since it effectively
 runs mypy twice -- the first time to find the missing stubs, and
 the second time to type check your code properly after mypy has
 installed the stubs. It also can make controlling stub versions harder,
-resulting in less reproducible type checking.
+resulting in less reproducible type checking — it might even install
+incompatible versions of your project's non-type dependencies, if the
+type stubs require them!
 
 By default, :option:`--install-types <mypy --install-types>` shows a confirmation prompt.
 Use :option:`--non-interactive <mypy --non-interactive>` to install all suggested

mypy/build.py

@@ -2783,11 +2783,10 @@ def module_not_found(
         msg, notes = reason.error_message_templates(daemon)
         if reason == ModuleNotFoundReason.NOT_FOUND:
             code = codes.IMPORT_NOT_FOUND
-        elif (
-            reason == ModuleNotFoundReason.FOUND_WITHOUT_TYPE_HINTS
-            or reason == ModuleNotFoundReason.APPROVED_STUBS_NOT_INSTALLED
-        ):
+        elif reason == ModuleNotFoundReason.FOUND_WITHOUT_TYPE_HINTS:
             code = codes.IMPORT_UNTYPED
+        elif reason == ModuleNotFoundReason.APPROVED_STUBS_NOT_INSTALLED:
+            code = codes.IMPORT_UNTYPED_STUBS_AVAILABLE
         else:
             code = codes.IMPORT
         errors.report(line, 0, msg.format(module=target), code=code)

mypy/errorcodes.py

@@ -34,6 +34,9 @@ def __init__(
             sub_code_map[sub_code_of.code].add(code)
         error_codes[code] = self
 
+    def is_import_related_code(self) -> bool:
+        return IMPORT in (self.code, self.sub_code_of)
+
     def __str__(self) -> str:
         return f"<ErrorCode {self.code}>"
 
@@ -114,7 +117,10 @@ def __hash__(self) -> int:
     "import-untyped", "Require that imported module has stubs", "General", sub_code_of=IMPORT
 )
 IMPORT_UNTYPED_STUBS_AVAILABLE: Final = ErrorCode(
-    "import-untyped-stubs-available", "Require that imported module (with known stubs) has stubs", "General", sub_code_of=IMPORT
+    "import-untyped-stubs-available",
+    "Require that imported module (with known stubs) has stubs",
+    "General",
+    sub_code_of=IMPORT,
 )
 NO_REDEF: Final = ErrorCode("no-redef", "Check that each name is defined once", "General")
 FUNC_RETURNS_VALUE: Final = ErrorCode(

mypy/errors.py

@@ -11,7 +11,7 @@
 
 from mypy import errorcodes as codes
 from mypy.error_formatter import ErrorFormatter
-from mypy.errorcodes import IMPORT, IMPORT_NOT_FOUND, IMPORT_UNTYPED, ErrorCode, mypy_error_codes
+from mypy.errorcodes import ErrorCode, mypy_error_codes
 from mypy.nodes import Context
 from mypy.options import Options
 from mypy.scope import Scope
@@ -583,7 +583,7 @@ def _add_error_info(self, file: str, info: ErrorInfo) -> None:
         self.error_info_map[file].append(info)
         if info.blocker:
             self.has_blockers.add(file)
-        if info.code in (IMPORT, IMPORT_UNTYPED, IMPORT_NOT_FOUND):
+        if info.code is not None and info.code.is_import_related_code():
             self.seen_import_error = True
 
     def get_watchers(self) -> Iterator[ErrorWatcher]:
@@ -630,7 +630,7 @@ def add_error_info(self, info: ErrorInfo) -> None:
             self.only_once_messages.add(info.message)
         if (
             self.seen_import_error
-            and info.code not in (IMPORT, IMPORT_UNTYPED, IMPORT_NOT_FOUND)
+            and (info.code is None or (not info.code.is_import_related_code()))
             and self.has_many_errors()
         ):
             # Missing stubs can easily cause thousands of errors about