feat(tests): add property-based tests for URL normalization and interface config parsing to improve robustness

tests/backend/test_http_url_guard_hypothesis.py

@@ -0,0 +1,43 @@
+# SPDX-License-Identifier: 0BSD
+
+"""Property tests for outbound loopback URL normalization."""
+
+from urllib.parse import urlparse
+
+import pytest
+from hypothesis import given, settings
+from hypothesis import strategies as st
+
+from meshchatx.src.backend.http_url_guard import (
+    UnsafeOutboundUrlError,
+    normalize_loopback_http_service_base,
+)
+
+
+@settings(max_examples=200, deadline=None)
+@given(s=st.text(max_size=4000))
+def test_normalize_loopback_only_raises_safe_error_or_returns_origin(s):
+    try:
+        out = normalize_loopback_http_service_base(s)
+    except UnsafeOutboundUrlError:
+        return
+    except Exception as e:
+        raise AssertionError(f"unexpected exception: {type(e).__name__}: {e}") from e
+
+    assert isinstance(out, str)
+    parsed = urlparse(out)
+    assert parsed.scheme in ("http", "https")
+    assert parsed.netloc
+    assert "@" not in parsed.netloc
+    host = (parsed.hostname or "").lower().strip("[]")
+    assert host in ("127.0.0.1", "localhost", "::1")
+    assert parsed.path in ("", "/")
+    assert parsed.query == ""
+    assert parsed.fragment == ""
+
+
+@settings(max_examples=80, deadline=None)
+@given(s=st.one_of(st.none(), st.binary(min_size=0, max_size=256)))
+def test_normalize_loopback_rejects_non_string(s):
+    with pytest.raises(UnsafeOutboundUrlError):
+        normalize_loopback_http_service_base(s)

tests/backend/test_interface_config_parser_hypothesis.py

@@ -0,0 +1,30 @@
+# SPDX-License-Identifier: 0BSD
+
+"""Property tests for Reticulum-style interface config parsing."""
+
+from hypothesis import given, settings
+from hypothesis import strategies as st
+
+from meshchatx.src.backend.interface_config_parser import InterfaceConfigParser
+
+
+@settings(max_examples=150, deadline=None)
+@given(text=st.text(max_size=8000))
+def test_interface_config_parse_never_raises(text):
+    result = InterfaceConfigParser.parse(text)
+    assert isinstance(result, list)
+    for iface in result:
+        assert isinstance(iface, dict)
+        assert "name" in iface
+        assert isinstance(iface["name"], str)
+
+
+@settings(max_examples=120, deadline=None)
+@given(lines=st.lists(st.text(max_size=400), max_size=120))
+def test_interface_config_parse_joined_lines_never_raises(lines):
+    text = "\n".join(lines)
+    result = InterfaceConfigParser.parse(text)
+    assert isinstance(result, list)
+    for iface in result:
+        assert isinstance(iface, dict)
+        assert "name" in iface