From: SZEDER Gábor Date: Sat, 28 Aug 2021 09:47:26 GMT Subject: Re: [PATCH] t5582: remove spurious 'cd "$D"' line Message-ID: <20210828094726.GG2257957@szeder.dev> In-Reply-To: On Wed, Aug 25, 2021 at 09:12:37AM -0700, Junio C Hamano wrote: > Jeff King writes: > > > Hmm. I think that one is different, in that the "cd" is not redundant, > > but wrong. But it turns out not to matter to the test. ;) > > Funny. > > We are lucky because 'cd ""' stays in the same repository as the > current one and not to a random place, Actually, the results of 'cd ""' are unspecified, though most shells do as you said. Do we want something like this? --- >8 --- Subject: [PATCH] test-lib: catch 'cd "$dir"' with unset variable We just had to fix two test cases [1] that invoked 'cd "$dir"' while the given variable was accidentally unset. While POSIX states that if 'cd's directory parameter "is an empty string, the results are unspecified" [2], most shells treat this as a no-op [3], i.e. they neither change directory nor return error, that's why both of those tests happened to succeed on common shells, and thus these issues remained hidden for a while. Catch 'cd ""' by adding a thin wrapper function overriding the shell's 'cd' command to verify the non-emptiness of its parameters and call BUG if necessary. [1] bd72824c60 (t5582: remove spurious 'cd "$D"' line, 2021-08-23) c21b2511c2 (t5323: drop mentions of "master", 2021-08-24) [2] https://pubs.opengroup.org/onlinepubs/9699919799/utilities/cd.html [3] 'ksh' and 'ksh93' are the only shells I found that error out on 'cd ""' with "cd: bad directory" (though these shells are unable to run significant portion of our test sute anyway). Signed-off-by: SZEDER Gábor --- t/test-lib.sh | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/t/test-lib.sh b/t/test-lib.sh index abcfbed6d6..06b75d8430 100644 --- a/t/test-lib.sh +++ b/t/test-lib.sh @@ -1436,6 +1436,14 @@ EMPTY_TREE=$(test_oid empty_tree) EMPTY_BLOB=$(test_oid empty_blob) _z40=$ZERO_OID +cd () { + if test -z "$@" + then + BUG "cd invoked with empty parameter" + fi + command cd "$@" +} + # Provide an implementation of the 'yes' utility; the upper bound # limit is there to help Windows that cannot stop this loop from # wasting cycles when the downstream stops reading, so do not be -- 2.33.0.358.g803110d36e