feat: open a group, a folder or a file from a #/name@owner link

A group can now be reached by the handle shown under its name, and a path
after it points inside the group: #/name@owner/root/dir/file downloads the
file and opens Files on its folder; a folder opens Files there. The handle
is resolved in the client against the account's own /v1/groups/mine, so no
hub route answers for a name and nobody can probe for one. While a group is
open the address shows the handle (replace, no history entry); a linked path
is taken out of the address once acted on, so a reload does not download
twice.

Signing in no longer sends everyone home: the form stood in for the page the
address named, and that is where a link opened signed out was going.

group-link.js holds the parsing and lookups, executed whole by
test_group_link.py; harness/group_link_probe.py drives the router in Chrome.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

1 files changed, 67 insertions, 0 deletions

diff --git a/packages/meshbay-hub/tests/test_group_link_flow.py b/packages/meshbay-hub/tests/test_group_link_flow.py
new file mode 100644
index 0000000..eb6a353
--- /dev/null
+++ b/packages/meshbay-hub/tests/test_group_link_flow.py
@@ -0,0 +1,67 @@
+"""
+A group link, opened in the real application (harness/group_link_probe.py).
+
+`test_group_link.py` holds the parsing and the lookups; this is where they meet
+the router. A handle opens the group's page, and an id opens it with the handle
+in the address; a path waits in the address for the index to say what it is; a
+handle the account does not know is said to be unknown without the hub ever
+being asked about it; and signed out, the sign-in form stands in for the page
+with the address left alone, which is what lets signing in land there.
+"""
+
+import json
+import shutil
+import subprocess
+import sys
+from pathlib import Path
+
+import pytest
+
+HARNESS = Path(__file__).parent / "harness" / "group_link_probe.py"
+GROUP_HREF = "#/group/0f8fad5b-d9cb-469f-a165-70867728950e"
+FILE_LINK = "#/demo@someowner/backup/city_2015/backup/IMG_0001.JPG"
+
+
+@pytest.fixture(scope="module")
+def cases():
+    if shutil.which("google-chrome") is None:
+        pytest.skip("Chrome is not available")
+    proc = subprocess.run([sys.executable, str(HARNESS)],
+                          capture_output=True, text=True, timeout=240)
+    assert proc.returncode == 0, f"probe failed: {proc.stdout}{proc.stderr}"
+    out = {c["case"]: c for c in json.loads(proc.stdout)}
+    for c in out.values():
+        assert "error" not in c, c["error"]
+    return out
+
+
+@pytest.mark.parametrize("case", ["handle", "uuid", "file"])
+def test_a_handle_or_an_id_opens_the_group(cases, case):
+    c = cases[case]
+    assert c["group_page"] and c["group_title"] == "demo@someowner"
+    # Of two groups called "demo", the one whose owner the handle names.
+    assert c["active_sidebar"] == [GROUP_HREF]
+
+
+@pytest.mark.parametrize("case", ["handle", "uuid"])
+def test_the_address_shows_the_handle_without_a_history_entry(cases, case):
+    assert cases[case]["hash"] == "#/demo@someowner"
+    assert cases[case]["history_length"] == 1
+
+
+def test_a_path_stays_in_the_address_until_it_has_been_acted_on(cases):
+    assert cases["file"]["hash"] == FILE_LINK
+
+
+def test_an_unknown_handle_is_said_so_without_asking_the_hub(cases):
+    c = cases["unknown"]
+    assert not c["group_page"] and c["message"] and not c["spinner"]
+    assert c["hash"] == "#/demo@stranger1"
+    for case in cases.values():
+        assert not any("stranger1" in u or "@" in u for u in case["hub_calls"])
+
+
+def test_signed_out_the_form_stands_in_for_the_page(cases):
+    c = cases["signed_out"]
+    assert c["login_form"] and not c["group_page"]
+    assert c["hash"] == FILE_LINK