Concurrent MDC inserts with the same key fails

[mdedetrich]

These current MDCFutureSpec fails

• Write and get different values concurrently and mixed with Future first
• Write and get different values concurrently and mixed with Future second

These tests involve putting values into MDC with the same key but different values in separate task executions. i.e. We have 2 threads of logic running at once, both threads put use the same key but they put in different values.

The equivalent test which just uses Task (i.e. MDCBasicSpec) works fine, but when we start using Task mixed with Future (along with TracingScheduler) the equivalent logic fails.

[oleg-py]

It's probably not the cause, but shouldn't you be using runToFutureOpt in your tests? Otherwise the option enable context propagation is ignored

[mdedetrich]

Thanks! I forgot to do a push (I had runToFutureOpt locally). It didn't really change anything, so the issue is still there.

What I am going to work on however is to make the tests use randomly generated values to make sure that we don't have conflicting keys.