tests:
- input_series:
- series: 'join_1{a="1",b="2"}'
values: 1
- series: 'join_2{a="1",b="3"}'
values: 2
- series: 'join_2{a="1",b="4"}'
values: 3
promql_expr_test:
# This PromQL generates an error.
- expr: "join_1 + on(a) join_2"