fix(anta.tests): Cleaning up ISIS tests module

.codespellignore

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+toi

.pre-commit-config.yaml

@@ -83,6 +83,7 @@ repos:
         entry: codespell
         language: python
         types: [text]
+        args: ["--ignore-words", ".codespellignore"]
 
   - repo: https://github.com/pre-commit/mirrors-mypy
     rev: v1.14.1

anta/input_models/routing/isis.py

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+# Copyright (c) 2023-2025 Arista Networks, Inc.
+# Use of this source code is governed by the Apache License 2.0
+# that can be found in the LICENSE file.
+"""Module containing input models for routing IS-IS tests."""
+
+from __future__ import annotations
+
+from ipaddress import IPv4Address
+from typing import Any, Literal
+from warnings import warn
+
+from pydantic import BaseModel, ConfigDict
+
+from anta.custom_types import Interface
+
+
+class ISISInstance(BaseModel):
+    """Model for an IS-IS instance."""
+
+    model_config = ConfigDict(extra="forbid")
+    name: str
+    """The name of the IS-IS instance."""
+    vrf: str = "default"
+    """VRF context of the IS-IS instance."""
+    dataplane: Literal["MPLS", "mpls", "unset"] = "MPLS"
+    """Configured SR data-plane for the IS-IS instance."""
+    segments: list[Segment] | None = None
+    """List of IS-IS SR segments associated with the instance. Required field in the `VerifyISISSegmentRoutingAdjacencySegments` test."""
+
+    def __str__(self) -> str:
+        """Return a human-readable string representation of the ISISInstance for reporting."""
+        return f"Instance: {self.name} VRF: {self.vrf}"
+
+
+class Segment(BaseModel):
+    """Model for an IS-IS segment."""
+
+    model_config = ConfigDict(extra="forbid")
+    interface: Interface
+    """Local interface name."""
+    level: Literal[1, 2] = 2
+    """IS-IS level of the segment."""
+    sid_origin: Literal["dynamic", "configured"] = "dynamic"
+    """Origin of the segment ID."""
+    address: IPv4Address
+    """Adjacency IPv4 address of the segment."""
+
+    def __str__(self) -> str:
+        """Return a human-readable string representation of the Segment for reporting."""
+        return f"Local Intf: {self.interface} Adj IP Address: {self.address}"
+
+
+class ISISInterface(BaseModel):
+    """Model for an IS-IS enabled interface."""
+
+    model_config = ConfigDict(extra="forbid")
+    name: Interface
+    """Interface name."""
+    vrf: str = "default"
+    """VRF context of the interface."""
+    level: Literal[1, 2] = 2
+    """IS-IS level of the interface."""
+    count: int | None = None
+    """Expected number of IS-IS neighbors on this interface. Required field in the `VerifyISISNeighborCount` test."""
+    mode: Literal["point-to-point", "broadcast", "passive"] | None = None
+    """IS-IS network type of the interface. Required field in the `VerifyISISInterfaceMode` test."""
+
+    def __str__(self) -> str:
+        """Return a human-readable string representation of the ISISInterface for reporting."""
+        return f"Interface: {self.name} VRF: {self.vrf} Level: {self.level}"
+
+
+class InterfaceCount(ISISInterface):  # pragma: no cover
+    """Alias for the ISISInterface model to maintain backward compatibility.
+
+    When initialized, it will emit a deprecation warning and call the ISISInterface model.
+
+    TODO: Remove this class in ANTA v2.0.0.
+    """
+
+    def __init__(self, **data: Any) -> None:  # noqa: ANN401
+        """Initialize the InterfaceCount class, emitting a deprecation warning."""
+        warn(
+            message="InterfaceCount model is deprecated and will be removed in ANTA v2.0.0. Use the ISISInterface model instead.",
+            category=DeprecationWarning,
+            stacklevel=2,
+        )
+        super().__init__(**data)
+
+
+class InterfaceState(ISISInterface):  # pragma: no cover
+    """Alias for the ISISInterface model to maintain backward compatibility.
+
+    When initialized, it will emit a deprecation warning and call the ISISInterface model.
+
+    TODO: Remove this class in ANTA v2.0.0.
+    """
+
+    def __init__(self, **data: Any) -> None:  # noqa: ANN401
+        """Initialize the InterfaceState class, emitting a deprecation warning."""
+        warn(
+            message="InterfaceState model is deprecated and will be removed in ANTA v2.0.0. Use the ISISInterface model instead.",
+            category=DeprecationWarning,
+            stacklevel=2,
+        )
+        super().__init__(**data)
+
+
+class IsisInstance(ISISInstance):  # pragma: no cover
+    """Alias for the ISISInstance model to maintain backward compatibility.
+
+    When initialized, it will emit a deprecation warning and call the ISISInstance model.
+
+    TODO: Remove this class in ANTA v2.0.0.
+    """
+
+    def __init__(self, **data: Any) -> None:  # noqa: ANN401
+        """Initialize the IsisInstance class, emitting a deprecation warning."""
+        warn(
+            message="IsisInstance model is deprecated and will be removed in ANTA v2.0.0. Use the ISISInstance model instead.",
+            category=DeprecationWarning,
+            stacklevel=2,
+        )
+        super().__init__(**data)