[PATCH] ui: add optional timestamp to output

[Pierre-Yves David]

On 04/11/2017 07:49 PM, Bryan O'Sullivan wrote:
>
> On Tue, Apr 11, 2017 at 7:15 AM, Augie Fackler <raf at durin42.com
> <mailto:raf at durin42.com>> wrote:
>
>     I'm missing some context. Why do we want timestamps in our output
>     like this?

This is useful to audit the timing of various steps when debugging (eg: 
discovery, cache computations, etc…).

(I'm the one behind who motivated Mathieu to write this patch. I need 
this feature on a regular basis)

> That's what the ts command gives us on Linux. I don't think this needs
> to be integrated into Mercurial proper.

Yes, `ts` can do this. However, piping to `ts` enable buffered output 
for Python (and Mercurial). As a result the timestamp of line has no 
relation with the time it was requested in the code. Sure one can 
request non-buffered output, but at that point there start to be enough 
obstacle than is get in the "complex" territory when requesting a trace 
to a random user.

In addition, `tr` won't handle timestamp for buffered and remote output.

So I think this patches has value on its own.

Cheers,

-- 
Pierre-Yves David