From: Junio C Hamano Date: Fri, 05 Jan 2018 22:28:13 GMT Subject: Re: [PATCH] perf: amend the grep tests to test grep.threads Message-ID: In-Reply-To: <87o9m8asys.fsf@evledraar.gmail.com> Ævar Arnfjörð Bjarmason writes: >> Judging by the way the other side uses "test_perf $prereq ..." >> without quotes around it, I suspect you do expect it to be empty in >> some cases. It means you expect test_have_prereq is prepared to >> skip an empty prerequisite in a prereq list, but I do not recall >> writing that helper in such a way, so... >> >> PTHREADS${prereq:+,}$prereq >> >> or something along that line, perhaps? > > It's not, but a trailing comma at the end of the prereq list works since > test_have_prereq() relies on setting the IFS to ",", so as long as this > is portable: > ... > We could use the ${...} pattern above if you prefer, but since it > doesn't appear to be needed... I view that reasoning as depending more on how the helper happens to be implemented right now than working by design, though.