```json
{
  "files": [
    "client.py",
    "test_client.py"
  ],
  "edits": [
    {
      "file": "client.py",
      "operation": "modify",
      "description": "Add a default timeout to the httpx.Client initialization. This enforces request timeout handling without altering the public API signature of the wrapper's methods.",
      "code_before": "import httpx\n\nclass HttpClient:\n    def __init__(self):\n        self.client = httpx.Client()\n\n    def get(self, url):\n        return self.client.get(url)\n\n    def post(self, url, data=None):\n        return self.client.post(url, data=data)",
      "code_after": "import httpx\n\nclass HttpClient:\n    def __init__(self, timeout=10.0):\n        self.client = httpx.Client(timeout=timeout)\n\n    def get(self, url):\n        return self.client.get(url)\n\n    def post(self, url, data=None):\n        return self.client.post(url, data=data)"
    }
  ],
  "tests": [
    {
      "name": "test_timeout_is_enforced",
      "description": "Verify that a request to a slow endpoint raises an httpx.TimeoutException when the timeout is exceeded.",
      "code": "import httpx\nimport pytest\nfrom client import HttpClient\n\n@pytest.fixture\ndef client():\n    return HttpClient(timeout=1.0)\n\ndef test_timeout_is_enforced(client, httpx_mock):\n    httpx_mock.add_response(url='http://example.com/slow', delay=2.0)\n    with pytest.raises(httpx.TimeoutException):\n        client.get('http://example.com/slow')"
    },
    {
      "name": "test_default_timeout_applied",
      "description": "Verify that the default timeout is applied to the httpx.Client when no timeout is explicitly passed.",
      "code": "import httpx\nimport pytest\nfrom client import HttpClient\n\ndef test_default_timeout_applied():\n    client = HttpClient()\n    assert client.client.timeout.connect == 10.0\n    assert client.client.timeout.read == 10.0"
    },
    {
      "name": "test_request_succeeds_within_timeout",
      "description": "Verify that a request succeeds if it completes before the timeout.",
      "code": "import httpx\nimport pytest\nfrom client import HttpClient\n\n@pytest.fixture\ndef client():\n    return HttpClient(timeout=5.0)\n\ndef test_request_succeeds_within_timeout(client, httpx_mock):\n    httpx_mock.add_response(url='http://example.com/fast', delay=0.5)\n    response = client.get('http://example.com/fast')\n    assert response.status_code == 200"
    }
  ],
  "risks": [
    "Default timeout value (e.g., 10s) might be too short for large file downloads or slow network conditions, leading to unexpected TimeoutExceptions.",
    "Default timeout value might be too long for latency-sensitive applications, causing unnecessary blocking.",
    "If the wrapper is used in a synchronous context, a timeout will block the calling thread for the full duration of the timeout, potentially impacting application responsiveness.",
    "Existing code relying on the previous behavior (no explicit timeout, relying on httpx defaults or infinite wait) will now fail with a TimeoutException."
  ]
}
```