Mattermost-server: Support autocomplete for Display Name when searching in a channel,

[mattermod]

We should support autocomplete for Channel and user display names with spaces in the search box.

Observed:
If you type "in: Ask Anything", the space character hides the autocomplete

Expected
We need to support spaces for in: and from: search to support this, similar to the way we support spaces for autocomplete in a channel when @ is typed

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JIRA: https://mattermost.atlassian.net/browse/MM-23267

[shFrank]

Hi can I claim this?

[shFrank]

Hi,
I'm trying to set up my web app but encountered some issues. Currently, I cannot pass the make test nor do make run.

Below are my terminal result, my node and npm versions, and the error log.

I checked the documentation at https://developers.mattermost.com/contribute/webapp/unit-testing/#4-getting-jest-assertion-failures-at-lines-containing-expect-tobecalledwith-expect-tohavebeennthcalledwith-or-expect-tohavebeencalledtimes-when-running-make-test
but I did not find a solution there.

[shFrank]

@amyblais Hi, I have located the cause of the problem.
At search_channel_provider.jsx Line 37, the regex /\b(?:in|channel):\s(\S)$/i is causing parsing error. When the input contains space (eg. "Town Squ"), the regex will parse the string to null.
However, I'm not that proficient with regex, could you offer me some help about why it would parse the string into null?

[amyblais]

@esethna ^

[shFrank]

@esethna Hi, could you help me out?

[esethna]

Hi @shfrank, feel free to ask in our contributors channel and/or peer-to-peer help as a starting point?

https://community.mattermost.com/core/channels/peer-to-peer-help
https://community.mattermost.com/core/channels/tickets

cc// @amyblais