Add upgrade test to ensure oid-less doc references load correctly

tests/bwc/test_upgrade.py

@@ -566,3 +566,54 @@ def test_snapshot_compatibility(self):
                 self._process_on_stop()
                 prev_version = version
                 num_snapshot += 1
+
+class PreOidsFetchValueTest(NodeProvider, unittest.TestCase):
+
+    def test_pre_oid_references(self):
+        cluster = self._new_cluster('5.4.x', 3)
+        cluster.start()
+
+        with connect(cluster.node().http_url, error_trace=True) as conn:
+            c = conn.cursor()
+            c.execute("create table tbl (a text, b text) partitioned by (a)")
+            c.execute("insert into tbl (a, b) values ('foo1', 'bar1')")
+
+        for idx, node in enumerate(cluster):
+            new_node = self.upgrade_node(node, '5.8.5')
+            cluster[idx] = new_node
+
+        with connect(cluster.node().http_url, error_trace=True) as conn:
+            c = conn.cursor()
+            c.execute("alter table tbl add column c text")
+            c.execute("insert into tbl (a, b, c) values ('foo1', 'bar2', 'baz2')")
+            c.execute("insert into tbl (a, b, c) values ('foo2', 'bar1', 'baz1')")
+
+        for idx, node in enumerate(cluster):
+            new_node = self.upgrade_node(node, '5.9.x')
+            cluster[idx] = new_node
+
+        with connect(cluster.node().http_url, error_trace=True) as conn:
+            c = conn.cursor()
+            c.execute("insert into tbl (a, b, c) values ('foo1', 'bar3', 'baz3')")
+            c.execute("insert into tbl (a, b, c) values ('foo2', 'bar2', 'baz2')")
+            c.execute("insert into tbl (a, b, c) values ('foo3', 'bar1', 'baz1')")
+
+        for idx, node in enumerate(cluster):
+            new_node = self.upgrade_node(node, '5.10')
+            cluster[idx] = new_node
+
+        with connect(cluster.node().http_url, error_trace=True) as conn:
+            c = conn.cursor()
+            c.execute("insert into tbl (a, b, c) values ('foo1', 'bar4', 'baz4')")
+            c.execute("insert into tbl (a, b, c) values ('foo2', 'bar3', 'baz3')")
+            c.execute("insert into tbl (a, b, c) values ('foo3', 'bar2', 'baz2')")
+            c.execute("insert into tbl (a, b, c) values ('foo4', 'bar1', 'baz1')")
+
+            c.execute("refresh table tbl")
+
+            # LIMIT 10 forces the engine to go via _doc, which triggers the bug
+            # fixed by https://github.com/crate/crate/pull/17819
+            c.execute("select b from tbl limit 10")
+            result = c.fetchall()
+            for row in result:
+                self.assertIsNotNone(row[0])