[test/spec] Failing spec tests for recursive arithmetic evaluations

[akinomyoga]

spec/ble-idioms.test.sh mentioned in #653 (comment).

[andychu]

Great thanks! It's interesting to see which shells support it, and as usual you find a bug or two :)

Since dash and yash don't support any of it, you can just delete the assertions and delete them from the arg list test/spec.sh. One reason for the different spec files is so each file can run on different shells. dash doesn't support most features that bash, mksh, etc. do.

[akinomyoga]

995e256 I removed dash and yash from test/spec.sh ble-idioms. I left the assertions of these shells because ble-idioms can possibly contain other tests unrelated to recursive arithmetic evaluations in future and dash and yash may be revisited then.