On Mon, Nov 19, 2018 at 02:28:18PM +0100, SZEDER Gábor wrote: > The 'test_cmp_rev' helper is merely a wrapper around 'test_cmp' > checking the output of two 'git rev-parse' commands, which means that > its output on failure is not particularly informative, as it's > basically two OIDs with a bit of extra clutter of the diff header, but > without any indication of which two revisions have caused the failure: > > --- expect.rev 2018-11-17 14:02:11.569747033 +0000 > +++ actual.rev 2018-11-17 14:02:11.569747033 +0000 > @@ -1 +1 @@ > -d79ce1670bdcb76e6d1da2ae095e890ccb326ae9 > +139b20d8e6c5b496de61f033f642d0e3dbff528d > > It also pollutes the test repo with these two intermediate files, > though that doesn't seem to cause any complications in our current > tests (meaning that I couldn't find any tests that have to work around > the presence of these files by explicitly removing or ignoring them). > > Enhance 'test_cmp_rev' to provide a more useful output on failure with > less clutter: > > error: two revisions point to different objects: > 'HEAD^': d79ce1670bdcb76e6d1da2ae095e890ccb326ae9 > 'extra': 139b20d8e6c5b496de61f033f642d0e3dbff528d > > Doing so is more convenient when storing the OIDs outputted by 'git > rev-parse' in a local variable each, which, as a bonus, won't pollute > the repository with intermediate files. > > While at it, also ensure that 'test_cmp_rev' is invoked with the right > number of parameters, namely two. This is an improvement, in my opinion (and I agree that using your new BUG for this last part would be better still). It also saves a process in the common case. One question: > + else > + local r1 r2 > + r1=$(git rev-parse --verify "$1") && > + r2=$(git rev-parse --verify "$2") && > + if test "$r1" != "$r2" > + then > + cat >&4 <<-EOF > + error: two revisions point to different objects: > + '$1': $r1 > + '$2': $r2 > + EOF > + return 1 > + fi Why does this cat go to descriptor 4? I get why you'd want it to (it's meant for the user's eyes, and that's where 4 goes), but we do not usually bother to do so for our helper functions (like test_cmp). I don't think it matters usually in practice, because nobody tries to capture the stderr of test_cmp, etc. I don't think it would ever hurt, though. Should we be doing that for all the others, too? -Peff