[PATCH] t7900: use pwd -P in macOS maintenance test

$pfx is the basis for the expectation that launchd plist paths formed by `git maintenance start` will be compared against. These paths are formed in `git maintenance` by builtin/gc.c launchctl_service_filename(), which calls path.c interpolate_path() with real_home = 1, causing abspath.c strbuf_realpath() to resolve a canonical absolute path. Since $pfx is not determined according to the same realpath semantics, when t7900 is run from a working directory that contains a symbolic link in its path, the realpath operation will produce a different path than $pfx contains, although both paths logically reference the same directory. The test fails in this case.

Base $pfx on the physical working directory (pwd -P), with all symbolic links fully resolved, so that the path that the test expects matches what `git maintenance` generates, even when running from a working directory whose path contains a symbolic link.

Signed-off-by: Mark Mentovai <mark@chromium.org>
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 t/t7900-maintenance.sh | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)