I asked a similar question in the past:
(http://sourceforge.net/p/fish/mailman/message/32501848/)

and was pointed towards this issue:
#1362

On Sat, Mar 28, 2015 at 5:12 AM, demonking notifications@github.com wrote:

Hello,

I have a problem with command substitutions with pipes?

In bash-shell it would looks like this:

cd $(ls | percol)

execute the command between the $() and then output the information to cd.

But in fish-shell it doesn't seems to work ? or i'm making some mistakes?
cd (ls | percol)

Or is percol here the problem?

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#2002.

@aboisvert thx for you answer, it seems, that i have to fix it through more calls like xargetc

Thanks @aboisvert . Yes, dup of #1362. The issue is processes that expect to own the term when running inside command substitutions. We'll likely fix it in the release after the upcoming one.

Thanks for reporting this!