Automatically generate entity platform enum (#152193)

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

script/hassfest/__main__.py

@@ -19,6 +19,7 @@ from . import (
     dhcp,
     docker,
     icons,
+    integration_info,
     json,
     manifest,
     metadata,
@@ -44,6 +45,7 @@ INTEGRATION_PLUGINS = [
     dependencies,
     dhcp,
     icons,
+    integration_info,
     json,
     manifest,
     mqtt,

script/hassfest/integration_info.py

@@ -0,0 +1,42 @@
+"""Write integration constants."""
+
+from __future__ import annotations
+
+from .model import Config, Integration
+from .serializer import format_python
+
+
+def validate(integrations: dict[str, Integration], config: Config) -> None:
+    """Validate integrations file."""
+
+    if config.specific_integrations:
+        return
+
+    int_type = "entity"
+
+    domains = [
+        integration.domain
+        for integration in integrations.values()
+        if integration.manifest.get("integration_type") == int_type
+        # Tag is type "entity" but has no entity platform
+        and integration.domain != "tag"
+    ]
+
+    code = [
+        "from enum import StrEnum",
+        "class EntityPlatforms(StrEnum):",
+        f'    """Available {int_type} platforms."""',
+    ]
+    code.extend([f'    {domain.upper()} = "{domain}"' for domain in sorted(domains)])
+
+    config.cache[f"integrations_{int_type}"] = format_python(
+        "\n".join(code), generator="script.hassfest"
+    )
+
+
+def generate(integrations: dict[str, Integration], config: Config) -> None:
+    """Generate integration file."""
+    int_type = "entity"
+    filename = "entity_platforms"
+    platform_path = config.root / f"homeassistant/generated/{filename}.py"
+    platform_path.write_text(config.cache[f"integrations_{int_type}"])