From 029d681d1c1e1af825b445d2d096b27db74715cc Mon Sep 17 00:00:00 2001
From: epenet <6771947+epenet@users.noreply.github.com>
Date: Fri, 13 Feb 2026 14:10:37 +0000
Subject: [PATCH] Add pylint plugin to check constant usage

---
 pylint/plugins/hass_enforce_constants.py | 57 ++++++++++++++++++++++++
 pyproject.toml                           |  1 +
 2 files changed, 58 insertions(+)
 create mode 100644 pylint/plugins/hass_enforce_constants.py

diff --git a/pylint/plugins/hass_enforce_constants.py b/pylint/plugins/hass_enforce_constants.py
new file mode 100644
index 00000000000..66a25a3d793
--- /dev/null
+++ b/pylint/plugins/hass_enforce_constants.py
@@ -0,0 +1,57 @@
+"""Plugin to enforce type hints on specific functions."""
+
+from __future__ import annotations
+
+from astroid import nodes
+from pylint.checkers import BaseChecker
+from pylint.lint import PyLinter
+
+
+class HassEnforceConstantsChecker(BaseChecker):
+    """Checker for use of constants."""
+
+    name = "hass_enforce_constants"
+    priority = -1
+    msgs = {
+        "W7491": (
+            "Argument %s should be a DOMAIN constant in %s",
+            "hass-argument-domain-constant",
+            "Used when method argument should be a DOMAIN constant.",
+        ),
+    }
+
+    _in_test_module: bool
+
+    def visit_module(self, node: nodes.Module) -> None:
+        """Visit Module node."""
+        self._in_test_module = node.name.startswith("tests.")
+
+    def visit_call(self, node: nodes.Call) -> None:
+        """Visit Call node."""
+        if not self._in_test_module:
+            return
+
+        if isinstance(node.func, nodes.Name):
+            if node.func.name == "async_setup_component":
+                self._ensure_domain_argument(node, node.args[1])
+
+    def _ensure_domain_argument(
+        self, call_node: nodes.Call, arg_node: nodes.Argument
+    ) -> None:
+        if isinstance(arg_node, nodes.Attribute) and arg_node.attrname.endswith(
+            "DOMAIN"
+        ):
+            return
+        if isinstance(arg_node, nodes.Name) and arg_node.name.endswith("DOMAIN"):
+            return
+
+        self.add_message(
+            "hass-argument-domain-constant",
+            node=arg_node,
+            args=(arg_node.as_string(), call_node.func.as_string()),
+        )
+
+
+def register(linter: PyLinter) -> None:
+    """Register the checker."""
+    linter.register_checker(HassEnforceConstantsChecker(linter))
diff --git a/pyproject.toml b/pyproject.toml
index 55f62b7484f..aef6469a2ce 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -125,6 +125,7 @@ load-plugins = [
   "hass_async_load_fixtures",
   "hass_decorator",
   "hass_enforce_class_module",
+  "hass_enforce_constants",
   "hass_enforce_greek_micro_char",
   "hass_enforce_sorted_platforms",
   "hass_enforce_super_call",