Better error message [skip CI]
Better error message [skip CI]


Former-commit-id: 8845ec6c47946525531e9ee8c2bbe5e6d8715f8f [formerly 8845ec6c47946525531e9ee8c2bbe5e6d8715f8f [formerly 83700fd5ef26dd8bd54420c8d355a23279d22e90]]
Former-commit-id: 84fac1f9f0a15d624882d4f7bdfb2bed10aa338e
Former-commit-id: 6681f1e66e917ea4af2bf7d1d8b4647e0ff2a8d3
gem/oq-engine,gem/oq-engine,gem/oq-engine,gem/oq-engine,gem/oq-engine