Re: [PATCH] tests: add a special setup where rebase.useBuiltin is off (Re: Git Test Coverage Report (v2.20.0-rc0))

From: Jonathan Nieder <jrnieder@gmail.com>
Date: Nov 19, 2018, 18:51 UTC
Message-ID: <20181119185109.GA47930@google.com>
In-Reply-To: <871s7g29zy.fsf@evledraar.gmail.com>

Ævar Arnfjörð Bjarmason wrote:

> On Mon, Nov 19 2018, Derrick Stolee wrote:

Show 10 quoted lines

>> [...]
>> builtin/rebase.c
>> 62c23938fa 55) return env;
>> [...]
>> Ævar Arnfjörð Bjarmason 62c23938f: tests: add a special setup
>> where rebase.useBuiltin is off
>
> This one would be covered with
> GIT_TEST_REBASE_USE_BUILTIN=false. Obviously trivial, but I wonder if
> the rest of the coverage would look different when passed through the various GIT_TEST_* options.

I wonder if we can do better for this kind of thing.

When I do routine development, I am not running tests with any non-default flags. So why should tests run with non-default flags count toward coverage? Is there a way to make the default test settings dip their feet into some non-default configurations, without running the full battery of tests and slowing tests down accordingly? E.g. is there some kind of smoke test that rebase with useBuiltin=false works at all that could run, even if I am not running the full battery of rebase tests?

That's a bit of a non sequitor for this example, which is actual code to handle GIT_TEST_REBASE_USE_BUILTIN, though. For it, I wonder why we need rebase.c to understand the envvar --- couldn't test-lib.sh take care of setting rebase.useBuiltin to false when it's set?

Thanks, Jonathan