Refactor pylint plugins to use match statements (#168894)

pylint/plugins/hass_enforce_config_entry_unique_id_no_ip.py

@@ -124,34 +124,18 @@ def _check_subscript_or_call_ip(node: nodes.NodeNG) -> str | None:
     avoiding false positives from local variables named ``host`` used in
     attribute chains like ``host.api.mac_address``.
     """
-    # Subscript: data[CONF_HOST] or data["host"]
-    if isinstance(node, nodes.Subscript):
-        key = node.slice
-        if isinstance(key, nodes.Name) and key.name in _IP_HOST_NAMES:
-            return str(key.name)
-        if (
-            isinstance(key, nodes.Const)
-            and isinstance(key.value, str)
-            and key.value in _IP_HOST_NAMES
-        ):
-            return key.value
-
-    # Call: data.get(CONF_HOST) or data.get("host")
-    if (
-        isinstance(node, nodes.Call)
-        and isinstance(node.func, nodes.Attribute)
-        and node.func.attrname == "get"
-        and node.args
-    ):
-        first_arg = node.args[0]
-        if isinstance(first_arg, nodes.Name) and first_arg.name in _IP_HOST_NAMES:
-            return str(first_arg.name)
-        if (
-            isinstance(first_arg, nodes.Const)
-            and isinstance(first_arg.value, str)
-            and first_arg.value in _IP_HOST_NAMES
-        ):
-            return first_arg.value
+    match node:
+        # Subscript: data[CONF_HOST] or data["host"]
+        case nodes.Subscript(
+            slice=nodes.Name(name=val) | nodes.Const(value=str(val))
+        ) if val in _IP_HOST_NAMES:
+            return str(val)
+        # Call: data.get(CONF_HOST) or data.get("host")
+        case nodes.Call(
+            func=nodes.Attribute(attrname="get"),
+            args=[nodes.Name(name=val) | nodes.Const(value=str(val)), *_],
+        ) if val in _IP_HOST_NAMES:
+            return str(val)
 
     # Recurse into child nodes to catch embedded references (e.g. f-strings),
     # but skip function call arguments -- a call like get_unique_id(host)

pylint/plugins/hass_enforce_config_flow_no_polling.py

@@ -83,19 +83,14 @@ class HassEnforceConfigFlowNoPollingChecker(BaseChecker):
 
 def _get_schema_field_name(node: nodes.Call) -> str | None:
     """Extract the field name from vol.Required(...) or vol.Optional(...)."""
-    if not isinstance(node.func, nodes.Attribute):
-        return None
-    if node.func.attrname not in {"Required", "Optional"}:
-        return None
-    if not node.args:
-        return None
-
-    first_arg = node.args[0]
-    if isinstance(first_arg, nodes.Const) and isinstance(first_arg.value, str):
-        return first_arg.value
-    if isinstance(first_arg, nodes.Name):
-        return str(first_arg.name)
-    return None
+    match node:
+        case nodes.Call(
+            func=nodes.Attribute(attrname="Required" | "Optional"),
+            args=[nodes.Name(name=val) | nodes.Const(value=str(val)), *_],
+        ):
+            return str(val)
+        case _:
+            return None
 
 
 def register(linter: PyLinter) -> None:

pylint/plugins/hass_enforce_runtime_data.py

@@ -81,39 +81,31 @@ class HassEnforceRuntimeDataChecker(BaseChecker):
             return
 
         # Don't flag deletion: del hass.data[DOMAIN] or hass.data[DOMAIN].pop(...)
-        parent = node.parent
-        if isinstance(parent, nodes.Delete):
-            return
-        if (
-            isinstance(parent, nodes.Attribute)
-            and parent.attrname == "pop"
-            and isinstance(parent.parent, nodes.Call)
-        ):
-            return
+        match node.parent:
+            case nodes.Delete():
+                return
+            case nodes.Attribute(attrname="pop", parent=nodes.Call()):
+                return
 
         self.add_message("hass-use-runtime-data", node=node)
 
 
 def _is_hass_data_domain_access(node: nodes.Subscript) -> bool:
     """Return True if node is hass.data[DOMAIN] or self.hass.data[DOMAIN]."""
-    if not isinstance(node.value, nodes.Attribute):
-        return False
-    if node.value.attrname != "data":
-        return False
-
-    slice_node = node.slice
-    if not isinstance(slice_node, nodes.Name) or slice_node.name != "DOMAIN":
-        return False
-
-    expr = node.value.expr
-    if isinstance(expr, nodes.Name) and expr.name == "hass":
-        return True
-    return (
-        isinstance(expr, nodes.Attribute)
-        and expr.attrname == "hass"
-        and isinstance(expr.expr, nodes.Name)
-        and expr.expr.name == "self"
-    )
+    match node:
+        case nodes.Subscript(
+            value=nodes.Attribute(
+                expr=(
+                    nodes.Name(name="hass")
+                    | nodes.Attribute(expr=nodes.Name(name="self"), attrname="hass")
+                ),
+                attrname="data",
+            ),
+            slice=nodes.Name(name="DOMAIN"),
+        ):
+            return True
+        case _:
+            return False
 
 
 def _has_config_flow(integration: str, module: nodes.Module) -> bool: