Re: [PATCH 07/15] remote-mediawiki tests: guard test_cmp with test_path_is_file

Eric Sunshine [off-list ref] writes:

On Wed, Sep 16, 2020 at 8:17 AM Ævar Arnfjörð Bjarmason
[off-list ref] wrote:

quoted

Change a test that used a plain test_cmp to first check the file(s)
using test_path_is_file. If some of these file(s) don't exist (as
happened to me during debugging), test_cmp will emit a way less useful
message about the failure.

An alternative would be to update test_cmp() to present a more helpful
error message so that all test scripts can benefit rather than just
this script. By the way, were you testing with a reasonably recent
version of Git? I ask because test_cmp() was updated not long ago to
provide better diagnostics when one of the files is missing.

[1]: d572f52a64 (test_cmp: diagnose incorrect arguments, 2020-08-09)

Yes, you did this with the commit,

test_cmp() {
	test $# -eq 2 || BUG "test_cmp requires two arguments"
	if ! eval "$GIT_TEST_CMP" '"$@"'
	then
		test "x$1" = x- || test -e "$1" || BUG "test_cmp '$1' missing"
		test "x$2" = x- || test -e "$2" || BUG "test_cmp '$2' missing"
		return 1
	fi
}

and I do not immediately see why "test -e" shouldn't be "test -f".
It should ideally be "stdin is OK, otherwise it must be a readable
regular file".

Thanks.