Populate UI fields with -c, -r, --step-clients, and --step-time options

[Trouv]

Closes #1186

I had trouble thinking of test cases to write for this (I did write one), so if you have any ideas please let me know!

[codecov]

Codecov Report

Merging #1339 into master will decrease coverage by 0.28%.
The diff coverage is 33.33%.

@@            Coverage Diff             @@
##           master    #1339      +/-   ##
==========================================
- Coverage   81.06%   80.78%   -0.29%     
==========================================
  Files          24       24              
  Lines        2234     2243       +9     
  Branches      339      342       +3     
==========================================
+ Hits         1811     1812       +1     
- Misses        333      341       +8     
  Partials       90       90              

Impacted Files	Coverage Δ
locust/argument_parser.py	75.00% <ø> (ø)
locust/main.py	20.10% <0.00%> (-0.63%)	⬇️
locust/web.py	91.01% <ø> (-0.57%)	⬇️
locust/env.py	95.55% <100.00%> (+0.31%)	⬆️
locust/contrib/fasthttp.py	87.04% <0.00%> (-0.52%)	⬇️

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[Trouv]

I also noticed that web_port and web_host are not used in master right now. Should I go ahead and fix this in this PR or should there be a separate one?

[heyman]

I'm not sure about adding four extra parameters to the create_web_ui method whose only purpose is to prefill a text box. I think that I'd prefer to add an optional reference to the parsed argument options object, to the Environment instance, which could then be used to prefill the text inputs (if it's set).

I also noticed that web_port and web_host are not used in master right now. Should I go ahead and fix this in this PR or should there be a separate one?

Oh, nice catch. A separate PR for that would be great!

[Trouv]

I think that I'd prefer to add an optional reference to the parsed argument options object, to the Environment instance, which could then be used to prefill the text inputs (if it's set).

That's a great idea! I'll get on it

[cyberw]

I'm +1 to merge. Maybe a mention of this feature somewhere in the documentation would be good though.

[heyman]

Merged! Good job!

Maybe a mention of this feature somewhere in the documentation would be good though.

Added an entry to the changelog in 2d0cc67