beets/.github/problem-matchers/sphinx-build.json

{
  "problemMatcher": [
    {
      "owner": "sphinx-build",
      "severity": "error",
      "pattern": [
        {
          "regexp": "^(/[^:]+):((\\d+):)?(\\sWARNING:)?\\s*(.+)$",
          "file": 1,
          "line": 3,
          "message": 5
        }
      ]
    }
  ]
}