add option --cov-summary to show coverage summary in terminal

[flniu]

In our case, we want to see a brief summary about the total coverage and required coverage in CI console, instead of printing a full term report or opening the html report. So I add an option --cov-summary to output coverage summary in terminal.

[ionelmc]

Wouldn't an addition to --cov-report be better? Eg: --cov-report=summary.

[flniu]

At first, I thought about --cov-report=term-summary, however:

• The summary only includes total coverage and required coverage(optional); it's not much like a report.
• I need to consider existing report types and handle the logic if no other --cov-report is specified.

So I choose an easier way which add an option but has the least impact on existing logic.

[ionelmc]

My two concerns are:

• it doesn't really make sense to use both --cov-summary and --cov-report, as reports would show the total. The seem exclusive to me, that's why I suggested extending --cov-report.
• I have a preference for not adding lots of switches and knobs. Perhaps always showing some sort of summary is acceptable (eg: if there's no --cov-report=term*)?

[flniu]

Well, I agree not to add lots of switches.

I thought about our requirement again. In current version, when --cov-fail-under is specified and required coverage is not reached, a message like this will be output:

FAIL Required test coverage of 80% not reached. Total coverage: 75%

What we need is: when required coverage is reached, also output a message like:

Required test coverage of 80% reached. Total coverage: 85%

How about this plan?

[ionelmc]

If you mean changing --cov-fail-under to always show summary and adding no other option then I like it.

[flniu]

Yes, that is what I mean. I'll work on it. This pr can be closed then.