[julia-users] Just a noob question: why are some test-failing PR merged?

[Sisyphuss]

I had a glance at the closed PRs at the GitHub.

I found that some PRs didn't pass any/all tests (av,ci), but they still got 
merged. For example, this one 
<https://github.com/JuliaLang/julia/pull/15122>

So I wonder why