Re: [PATCH 05/15] t/Makefile: optimize chainlint self-test

[Fabian Stelzer <fs@gigacodes.de>]

On 13.12.2021 09:27, Eric Sunshine wrote:
>On Mon, Dec 13, 2021 at 5:22 AM Fabian Stelzer <fs@gigacodes.de> wrote:
>> On 13.12.2021 01:30, Eric Sunshine wrote:
>> > check-chainlint:
>> >+      sed -e '/^# LINT: /d' $(patsubst %,chainlint/%.test,$(CHAINLINTTESTS)) >'$(CHAINLINTTMP_SQ)'/tests && \
>> >+      cat $(patsubst %,chainlint/%.expect,$(CHAINLINTTESTS)) >'$(CHAINLINTTMP_SQ)'/expect && \
>> >+      $(CHAINLINT) '$(CHAINLINTTMP_SQ)'/tests >'$(CHAINLINTTMP_SQ)'/actual && \
>> >+      diff -u '$(CHAINLINTTMP_SQ)'/expect '$(CHAINLINTTMP_SQ)'/actual
>>
>> If I read this right you are relying on the order of the .test & .expect
>> files to match. I did something similar in a test prereq which resulted in a
>> bug when setting the test_output_dir to something residing in /dev/shm,
>> since the order of files in /dev/shm is reversed (at least on some
>> platforms). Even though this should work as is I could see this leading to a
>> similar bug in the future.
>
>It's not seen in the patch context, but earlier in the file we have:
>
>    CHAINLINTTESTS = $(sort $(...,$(wildcard chainlint/*.test)))
>
>which provides stability via `sort`, thus ensures that the order of
>the ".test" and ".expect" match.
>
>I think that addresses your concern (unless I misunderstand your observation).

Yes, thats what i meant. I didn't realize $CHAINLINTTESTS is already the 
sorted glob. Thanks for clarifying.

Personally i find the initial for loop variant to be the most readable.  
Ævars makefile targets could be very nice too, but especially:

+$(BUILT_CHAINLINTTESTS): | .build/chainlint
+$(BUILT_CHAINLINTTESTS): .build/%.actual: %
+       $(CHAINLINT) <$< | \
+	 sed -e '/^# LINT: /d' >$@ && \
+       diff -u $(basename $<).expect $@

i find very hard to grasp :/
I have no idea what is going on here: `<$< |` ?