Add validator to prevent integration domain overrides of core

[ludeeus]

Summary

This PR adds a new validator that checks whether a HACS integration is attempting to override a domain that already exists in Home Assistant core. This prevents accidental or intentional conflicts with core integrations.

Key Changes

• New validator: core_domain_override.py - Validates that integration domains don't conflict with core Home Assistant domains

  • Fetches the list of core integration domains from https://next.home-assistant.io/integrations.json
  • Uses the "next" site to catch domains landing in upcoming releases before they ship
  • Skips validation if no domain is defined (handled by integration_manifest check instead)
  • Handles fetch failures and invalid JSON gracefully with appropriate error messages

• Comprehensive test coverage: test_core_domain_override_check.py with 5 test cases

  • Domain not in core (passes validation)
  • Domain overrides core domain (fails validation)
  • Core integrations fetch failure (fails validation)
  • Invalid JSON response (fails validation)
  • No domain defined (skips fetch, passes validation)

• Integration into validation pipeline: Updated action tests to include the new validator

  • Check count increased from 9 to 10 for integration validation
  • Updated all relevant test snapshots and logs

Implementation Details

• Validator only applies to HacsCategory.INTEGRATION repositories
• Gracefully handles network errors and malformed responses by raising ValidationException
• Documentation link provided: Add core domain override check documentation documentation#700
• Added test fixtures and API usage snapshots for proper test isolation

[Copilot]

Pull request overview

This PR introduces a new validation step in the HACS action validation pipeline to detect when an integration’s manifest domain conflicts with an existing Home Assistant core integration domain, using the next.home-assistant.io/integrations.json domain list to catch upcoming core additions.

Changes:

• Added core_domain_override validator that fetches core integration domains and fails validation on domain collisions.
• Added dedicated validator tests and updated action/validation snapshots (API usage + logs) to account for the new check.
• Added proxy fixture for next.home-assistant.io/integrations.json and updated action test setup to mock the new endpoint.

Reviewed changes

Copilot reviewed 15 out of 20 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
custom_components/hacs/validate/core_domain_override.py	New validator that fetches core domains and blocks domain overrides.
tests/validate/test_core_domain_override_check.py	Test coverage for pass/fail/skip and error conditions for the new validator.
tests/action/test_hacs_action_integration.py	Updates action test to mock the new endpoint and adjust expected check counts.
tests/fixtures/proxy/next.home-assistant.io/integrations.json	Adds proxy fixture for the new external endpoint used by the validator.
tests/snapshots/api-usage/tests/validate/test_core_domain_override_check*.json	Captures expected external calls for the new validator tests.
tests/snapshots/api-usage/tests/validate/test_async_run_repository_checkstest-async-run-repository-checks.json	Updates expected external calls due to the new validator being executed.
tests/snapshots/api-usage/tests/action/test_hacs_action_integration*.json	Updates action snapshots to include the new endpoint call.
tests/snapshots/action/test_hacs_action_integration/*.log	Updates logs to include the new validator and updated check counts.

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.