From a8c23cb526773f3a55ce5d4c315e51ffa0782ad8 Mon Sep 17 00:00:00 2001
From: Marc Mueller <30130371+cdce8p@users.noreply.github.com>
Date: Sun, 28 Aug 2022 12:48:24 +0200
Subject: [PATCH] Add option for strict-error-codes

---
 docs/source/command_line.rst         |  8 ++++++++
 docs/source/config_file.rst          | 11 +++++++++++
 mypy/errorcodes.py                   | 10 +++++++++-
 mypy/errors.py                       |  4 ++++
 mypy/main.py                         | 14 ++++++++++++++
 mypy/options.py                      |  2 ++
 test-data/unit/check-errorcodes.test |  4 ++++
 7 files changed, 52 insertions(+), 1 deletion(-)

diff --git a/docs/source/command_line.rst b/docs/source/command_line.rst
index 41a27a6d1b546..6141b2fae04be 100644
--- a/docs/source/command_line.rst
+++ b/docs/source/command_line.rst
@@ -618,6 +618,14 @@ of the above sections.
 
        assert text is not None  # OK, check against None is allowed as a special case.
 
+.. option:: --strict-error-codes
+
+    Enable additional error codes, disabled by default. You can see the list
+    of codes enabled by this flag in the full :option:`mypy --help` output.
+
+    Note: the exact list of codes enabled by running :option:`--strict-error-codes`
+    may change over time.
+
 .. option:: --strict
 
     This flag mode enables all optional error checking flags.  You can see the
diff --git a/docs/source/config_file.rst b/docs/source/config_file.rst
index 34158ac791dbd..7db4749b3eb27 100644
--- a/docs/source/config_file.rst
+++ b/docs/source/config_file.rst
@@ -679,6 +679,17 @@ section of the command line docs.
    Prohibit equality checks, identity checks, and container checks between
    non-overlapping types.
 
+.. confval:: strict_error_codes
+
+    :type: boolean
+    :default: False
+
+   Enable additional error codes, disabled by default. You can see the list
+   of codes enabled by this flag in the full :option:`mypy --help` output.
+
+   Note: the exact list of codes enabled by running :confval:`strict_error_codes`
+   may change over time.
+
 .. confval:: strict
 
     :type: boolean
diff --git a/mypy/errorcodes.py b/mypy/errorcodes.py
index 955b30f915b53..942542ac6111a 100644
--- a/mypy/errorcodes.py
+++ b/mypy/errorcodes.py
@@ -12,12 +12,19 @@
 
 class ErrorCode:
     def __init__(
-        self, code: str, description: str, category: str, default_enabled: bool = True
+        self,
+        code: str,
+        description: str,
+        category: str,
+        default_enabled: bool = True,
+        *,
+        strict_enabled: bool = False,
     ) -> None:
         self.code = code
         self.description = description
         self.category = category
         self.default_enabled = default_enabled
+        self.strict_enabled = strict_enabled
         error_codes[code] = self
 
     def __str__(self) -> str:
@@ -144,6 +151,7 @@ def __str__(self) -> str:
     "Warn about '# type: ignore' comments which do not have error codes",
     "General",
     default_enabled=False,
+    strict_enabled=True,
 )
 UNUSED_AWAITABLE: Final = ErrorCode(
     "unused-awaitable",
diff --git a/mypy/errors.py b/mypy/errors.py
index a6f50ff34de2a..3911588903a44 100644
--- a/mypy/errors.py
+++ b/mypy/errors.py
@@ -590,14 +590,18 @@ def is_error_code_enabled(self, error_code: ErrorCode) -> bool:
         if self.options:
             current_mod_disabled = self.options.disabled_error_codes
             current_mod_enabled = self.options.enabled_error_codes
+            strict_error_codes = self.options.strict_error_codes
         else:
             current_mod_disabled = set()
             current_mod_enabled = set()
+            strict_error_codes = False
 
         if error_code in current_mod_disabled:
             return False
         elif error_code in current_mod_enabled:
             return True
+        elif strict_error_codes and error_code.strict_enabled:
+            return True
         else:
             return error_code.default_enabled
 
diff --git a/mypy/main.py b/mypy/main.py
index 695a1917a1928..dc4e506c1b99d 100644
--- a/mypy/main.py
+++ b/mypy/main.py
@@ -824,6 +824,20 @@ def add_invertible_flag(
         group=strictness_group,
     )
 
+    strict_error_code_names = [name for name, code in error_codes.items() if code.strict_enabled]
+    strict_error_codes_help = (
+        "Enable additional error codes, disabled by default; "
+        f"enables the following codes: {', '.join(strict_error_code_names)}"
+    )
+
+    add_invertible_flag(
+        "--strict-error-codes",
+        default=False,
+        strict_flag=True,
+        help=strict_error_codes_help,
+        group=strictness_group,
+    )
+
     strict_help = "Strict mode; enables the following flags: {}".format(
         ", ".join(strict_flag_names)
     )
diff --git a/mypy/options.py b/mypy/options.py
index fb7bb8e43bbb3..fddcdabc2bd70 100644
--- a/mypy/options.py
+++ b/mypy/options.py
@@ -190,6 +190,8 @@ def __init__(self) -> None:
         # Variable names considered False
         self.always_false: list[str] = []
 
+        self.strict_error_codes = False
+
         # Error codes to disable
         self.disable_error_code: list[str] = []
         self.disabled_error_codes: set[ErrorCode] = set()
diff --git a/test-data/unit/check-errorcodes.test b/test-data/unit/check-errorcodes.test
index a599a6e754189..4595d30ca25a5 100644
--- a/test-data/unit/check-errorcodes.test
+++ b/test-data/unit/check-errorcodes.test
@@ -925,3 +925,7 @@ def f(d: D, s: str) -> None:
 [case testRecommendErrorCode]
 # type: ignore[whatever]  # E: type ignore with error code is not supported for modules; use `# mypy: disable-error-code=...`  [syntax]
 1 + "asdf"
+
+[case testStrictErrorCodes]
+# flags: --strict-error-codes
+var: bool = 1  # type: ignore  # E: "type: ignore" comment without error code (consider "type: ignore[assignment]" instead)  [ignore-without-code]