1 files changed, 74 insertions, 0 deletions
diff --git a/packages/meshbay-hub/tests/test_versions_agree.py b/packages/meshbay-hub/tests/test_versions_agree.py
new file mode 100644
index 0000000..4466c93
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+++ b/packages/meshbay-hub/tests/test_versions_agree.py
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+"""
+Every package in this repository carries the same version.
+
+They are built, deployed and updated together — hub, node, common and the
+desktop client — so a version that differs is not a statement about that
+package, it is a mistake nobody has noticed yet.
+
+**Found on 2026-09-09, on the MNP 3.0 flag day.** `meshbay-client`'s
+`package.json` had drifted to `1.0.0` while every Python package was on
+`0.12.0`. That was invisible until the hub started publishing a minimum client
+version and the client started comparing itself against it — at which point an
+installed client announcing `1.0.0` sorted *above* a minimum of `0.13.0` and
+walked straight through the gate meant to stop it. A version nobody reads is
+free to be wrong; the moment something compares it, it is load-bearing.
+"""
+
+import json
+import re
+from pathlib import Path
+
+import pytest
+
+ROOT = Path(__file__).resolve().parents[3]
+PACKAGES = ROOT / "packages"
+
+
+def _python_versions() -> dict[str, str]:
+    found = {}
+    for pyproject in sorted(PACKAGES.glob("*/pyproject.toml")):
+        m = re.search(r'^version = "([^"]+)"', pyproject.read_text(), re.M)
+        if m:
+            found[f"{pyproject.parent.name}/pyproject.toml"] = m.group(1)
+    for init in sorted(PACKAGES.glob("*/src/*/__init__.py")):
+        m = re.search(r'^__version__ = "([^"]+)"', init.read_text(), re.M)
+        if m:
+            found[f"{init.parent.name}/__init__.py"] = m.group(1)
+    return found
+
+
+def _client_version() -> str | None:
+    pkg = PACKAGES / "meshbay-client" / "package.json"
+    if not pkg.exists():
+        return None
+    return json.loads(pkg.read_text()).get("version")
+
+
+@pytest.mark.skipif(not PACKAGES.is_dir(), reason="package layout not present")
+def test_every_package_carries_the_same_version():
+    versions = _python_versions()
+    assert versions, "no package versions found at all — has the layout moved?"
+    client = _client_version()
+    if client is not None:
+        versions["meshbay-client/package.json"] = client
+    distinct = sorted(set(versions.values()))
+    assert len(distinct) == 1, (
+        "packages disagree about the version: "
+        + ", ".join(f"{k}={v}" for k, v in sorted(versions.items())))
+
+
+@pytest.mark.skipif(not PACKAGES.is_dir(), reason="package layout not present")
+def test_the_hub_will_not_refuse_the_client_it_ships_with():
+    """`MIN_CLIENT_VERSION` is compared against a client's own version, so a
+    minimum above the version being built would lock out the very build being
+    released — the one failure this field can cause that nobody would think to
+    test for by hand."""
+    from meshbay_hub.api.hub import MIN_CLIENT_VERSION
+
+    client = _client_version()
+    if client is None:
+        pytest.skip("desktop client sources not present")
+    as_numbers = lambda v: [int(n) for n in v.split(".")]   # noqa: E731
+    assert as_numbers(MIN_CLIENT_VERSION) <= as_numbers(client), (
+        f"the hub requires client {MIN_CLIENT_VERSION} but this tree builds "
+        f"{client}")