On Sat, Jun 05, 2021 at 08:11:24PM +0200, René Scharfe wrote: > The parallel checkout tests fail when run with /bin/dash on MacOS 11.4, > reporting the following error: > > ./t2080-parallel-checkout-basics.sh: 33: local: 0: bad variable name > > That's because wc's output contains leading spaces and this version of > dash erroneously expands the variable declaration as "local workers= 0", > i.e. it tries to set the "workers" variable to the empty string and also > declare a variable named "0", which not a valid name. This is a known > dash bug (https://bugs.launchpad.net/ubuntu/+source/dash/+bug/139097). Perhaps a more accurate wording for this bug would be: ... and even fairly recent versions of dash erroneously perform field splitting on the expansion of the command substitution before assigning it to a local variable. I think the relevant part of POSIX is section 2.9.1 Simple Commands: 4. Each variable assignment shall be expanded for tilde expansion, parameter expansion, command substitution, arithmetic expansion, and quote removal prior to assigning the value. https://pubs.opengroup.org/onlinepubs/9699919799/utilities/V3_chap02.html#tag_18_09_01 Note that it didn't mention field splitting; though POSIX doesn't specifies local variables in the first place, so... Anyway, this bug has been fixed in v0.5.11 (2020-06-01). This is an old bug, it was already present in v0.5.5 (2009-01-13); I didn't check earlier versions. > Work around it by passing the command output directly to test instead of > storing it in a variable first. While at it, let grep count the number > of lines instead of piping its output to wc, which is a bit shorter and > more efficient. A more debug-friendly alternative would be to save 'grep's output to a temporary file and use 'test_line_count = $expected_workers'. > Helped-by: Matheus Tavares Bernardino <matheus.bernardino@xxxxxx> > Signed-off-by: René Scharfe <l.s.r@xxxxxx> > --- > Changes since v1: > - Explain the root cause. > - Get rid of the local variable "workers". > - Adjust title accordingly. > - Still use grep -c, though. > - Remove input redirection. > > t/lib-parallel-checkout.sh | 3 +-- > 1 file changed, 1 insertion(+), 2 deletions(-) > > diff --git a/t/lib-parallel-checkout.sh b/t/lib-parallel-checkout.sh > index 21f5759732..66350d5207 100644 > --- a/t/lib-parallel-checkout.sh > +++ b/t/lib-parallel-checkout.sh > @@ -27,8 +27,7 @@ test_checkout_workers () { > rm -f "$trace_file" && > GIT_TRACE2="$(pwd)/$trace_file" "$@" 2>&8 && > > - local workers=$(grep "child_start\[..*\] git checkout--worker" "$trace_file" | wc -l) && > - test $workers -eq $expected_workers && > + test $(grep -c "child_start\[..*\] git checkout--worker" "$trace_file") -eq $expected_workers && > rm "$trace_file" > } 8>&2 2>&4 > > -- > 2.31.1 >
