Edges not retrievable without committing transaction

[james10424]

Transaction works with documents, but not edges.

Platform info:

• os: MacOS 12.6
• Arango: 3.10.2
• python-arango: 7.5.5
• python: 3.10.0

Sample code to reproduce:

def test_transaction():
    client = ArangoClient()
    sys_db = client.db(
        "_system", username="username", password="password"
    )
    # drop and recreate the test db
    sys_db.delete_database("test", ignore_missing=True)
    sys_db.create_database("test")
    db = client.db(
        "test", username="username", password="password"
    )
    # create stuff
    graph = db.create_graph("graph")
    graph.create_vertex_collection("a")
    graph.create_vertex_collection("b")
    edge = graph.create_edge_definition(
        edge_collection="edge",
        from_vertex_collections=["a"],
        to_vertex_collections=["b"],
    )

    tx = db.begin_transaction(
        read=["a", "b", "edge"],
        write=["a", "b", "edge"],
    )
    graph = tx.graph("graph")
    # does not work with regular collection either
    a = graph.vertex_collection("a")
    b = graph.vertex_collection("b")
    a_doc = a.insert({})
    b_doc = b.insert({})
    # verify that they are retrievable without committing
    assert a.get(a_doc["_key"]) is not None
    assert b.get(b_doc["_key"]) is not None
    edge = graph.edge_collection("edge")
    # link a and b
    edge.link(a_doc["_id"], b_doc["_id"])
    edges = edge.edges(a_doc["_id"])
    # this fails without committing
    # tx.commit_transaction()
    assert len(edges["edges"]) == 1
    tx.abort_transaction()