Fix mypy for pydantic v1 and v2

This required that we allow unused igores since the location
of the ignores depends on the version of pydantic and mypy
always picks up the first definition it sees even if that
is a pydantic V2 code path and pydantic is v1.

mypy.ini

@@ -71,7 +71,7 @@ disallow_untyped_defs = True
 disallow_incomplete_defs = True
 strict_equality = True
 warn_unreachable = True
-warn_unused_ignores = True
+warn_unused_ignores = False
 
 # ...except the modules and subpackages below (can't find a way to do line
 # breaks in the lists of modules).

python/lsst/daf/butler/_compat.py

@@ -25,7 +25,7 @@
 
 import sys
 from collections.abc import Callable
-from typing import Any
+from typing import TYPE_CHECKING, Any
 
 from pydantic import BaseModel
 from pydantic.version import VERSION as PYDANTIC_VERSION
@@ -54,8 +54,8 @@ class _BaseModelCompat(BaseModel):
         def json(
             self,
             *,
-            include: set[int] | set[str] | dict[int, Any] | dict[str, Any] | None = None,
-            exclude: set[int] | set[str] | dict[int, Any] | dict[str, Any] | None = None,
+            include: set[int] | set[str] | dict[int, Any] | dict[str, Any] | None = None,  # type: ignore
+            exclude: set[int] | set[str] | dict[int, Any] | dict[str, Any] | None = None,  # type: ignore
             by_alias: bool = False,
             skip_defaults: bool | None = None,
             exclude_unset: bool = False,
@@ -84,9 +84,46 @@ def parse_obj(cls, obj: Any) -> Self:
             # Catch warnings and call BaseModel.parse_obj directly?
             return cls.model_validate(obj)
 
+        if TYPE_CHECKING and not PYDANTIC_V2:
+            # mypy sees the first definition of a class and ignores any
+            # redefinition. This means that if mypy is run with pydantic v1
+            # it will not see the classes defined in the else block below.
+
+            @classmethod
+            def model_construct(cls, _fields_set: set[str] | None = None, **values: Any) -> Self:
+                return cls()
+
+            @classmethod
+            def model_validate(
+                cls,
+                obj: Any,
+                *,
+                strict: bool | None = None,
+                from_attributes: bool | None = None,
+                context: dict[str, Any] | None = None,
+            ) -> Self:
+                return cls()
+
+            def model_dump_json(
+                self,
+                *,
+                indent: int | None = None,
+                include: set[int] | set[str] | dict[int, Any] | dict[str, Any] | None = None,
+                exclude: set[int] | set[str] | dict[int, Any] | dict[str, Any] | None = None,
+                by_alias: bool = False,
+                exclude_unset: bool = False,
+                exclude_defaults: bool = False,
+                exclude_none: bool = False,
+                round_trip: bool = False,
+                warnings: bool = True,
+            ) -> str:
+                return ""
+
 else:
 
     class _BaseModelCompat(BaseModel):  # type:ignore[no-redef]
+        """Methods from pydantic v2 that can be used in pydantic v1."""
+
         @classmethod
         def model_validate(
             cls,
@@ -112,10 +149,14 @@ def model_dump_json(
             warnings: bool = True,
         ) -> str:
             return self.json(
-                include=include,
-                exclude=exclude,
+                include=include,  # type: ignore
+                exclude=exclude,  # type: ignore
                 by_alias=by_alias,
                 exclude_unset=exclude_unset,
                 exclude_defaults=exclude_defaults,
                 exclude_none=exclude_none,
             )
+
+        @classmethod  # type: ignore
+        def model_construct(cls, _fields_set: set[str] | None = None, **values: Any) -> Self:
+            return cls.construct(_fields_set=_fields_set, **values)

python/lsst/daf/butler/core/logging.py

@@ -269,7 +269,7 @@ def __str__(self) -> str:
 
 
 if PYDANTIC_V2:
-    from pydantic import RootModel
+    from pydantic import RootModel  # type: ignore
 
     class _ButlerLogRecords(RootModel):
         root: list[ButlerLogRecord]

python/lsst/daf/butler/registry/wildcards.py

@@ -259,7 +259,7 @@ def process(element: Any, alreadyCoerced: bool = False) -> EllipsisType | None:
 
 
 if PYDANTIC_V2:
-    from pydantic import RootModel
+    from pydantic import RootModel  # type: ignore
 
     class _CollectionSearch(RootModel):
         root: tuple[str, ...]