[PATCH] submodule: add more exhaustive up-path testing

["Ævar Arnfjörð Bjarmason" <avarab@gmail.com>]

The tests added in 63e95beb08 ("submodule: port resolve_relative_url
from shell to C", 2016-04-15) didn't do a good job of testing various
up-path invocations where the up-path would bring us beyond even the
URL in question without emitting an error.

These results look nonsensical, but it's worth exhaustively testing
them before fixing any of this code, so we can see which of these
cases were changed.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
---

The reason I started to poke at this was because I wanted to add
support for relative URLs like //group/project.

This solves the problem of there being e.g. a myhost.com/group/project
which includes a ../submodule submodule pointing to
myhost.com/group/submodule , and me wanting to fork it to
myhost.com/myuser/project.

But of course with ../submodule the relative URL will point to
myhost.com/myuser/submodule, which won't exist.

So I was hoping to find some point in the relative URL code where we
were actually aware of what the host boundary was, so I could just cut
off everything after that if //group/project was provided, strip off
one slash to make it /group/project, and call it a day.

But as the tests below show the code isn't aware of that at all, and
will happily trample over the host(name) to produce nonsensical
results.

So I think these tests are worthwihle in themselves, but would like
some advice on how to proceed with that from someone more familiar
with submodules.

 t/t0060-path-utils.sh | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/t/t0060-path-utils.sh b/t/t0060-path-utils.sh
index 21a8b53132..cd74c0a471 100755
--- a/t/t0060-path-utils.sh
+++ b/t/t0060-path-utils.sh
@@ -330,6 +330,9 @@ test_submodule_relative_url "(null)" "../foo" "../submodule" "../submodule"
 test_submodule_relative_url "(null)" "./foo/bar" "../submodule" "foo/submodule"
 test_submodule_relative_url "(null)" "./foo" "../submodule" "submodule"
 test_submodule_relative_url "(null)" "//somewhere else/repo" "../subrepo" "//somewhere else/subrepo"
+test_submodule_relative_url "(null)" "//somewhere else/repo" "../../subrepo" "//subrepo"
+test_submodule_relative_url "(null)" "//somewhere else/repo" "../../../subrepo" "/subrepo"
+test_submodule_relative_url "(null)" "//somewhere else/repo" "../../../../subrepo" "subrepo"
 test_submodule_relative_url "(null)" "$(pwd)/subsuper_update_r" "../subsubsuper_update_r" "$(pwd)/subsubsuper_update_r"
 test_submodule_relative_url "(null)" "$(pwd)/super_update_r2" "../subsuper_update_r" "$(pwd)/subsuper_update_r"
 test_submodule_relative_url "(null)" "$(pwd)/." "../." "$(pwd)/."
@@ -344,10 +347,20 @@ test_submodule_relative_url "(null)" "file:///tmp/repo" "../subrepo" "file:///tm
 test_submodule_relative_url "(null)" "foo/bar" "../submodule" "foo/submodule"
 test_submodule_relative_url "(null)" "foo" "../submodule" "submodule"
 test_submodule_relative_url "(null)" "helper:://hostname/repo" "../subrepo" "helper:://hostname/subrepo"
+test_submodule_relative_url "(null)" "helper:://hostname/repo" "../../subrepo" "helper:://subrepo"
+test_submodule_relative_url "(null)" "helper:://hostname/repo" "../../../subrepo" "helper::/subrepo"
+test_submodule_relative_url "(null)" "helper:://hostname/repo" "../../../../subrepo" "helper::subrepo"
+test_submodule_relative_url "(null)" "helper:://hostname/repo" "../../../../../subrepo" "helper:subrepo"
+test_submodule_relative_url "(null)" "helper:://hostname/repo" "../../../../../../subrepo" ".:subrepo"
 test_submodule_relative_url "(null)" "ssh://hostname/repo" "../subrepo" "ssh://hostname/subrepo"
+test_submodule_relative_url "(null)" "ssh://hostname/repo" "../../subrepo" "ssh://subrepo"
+test_submodule_relative_url "(null)" "ssh://hostname/repo" "../../../subrepo" "ssh:/subrepo"
+test_submodule_relative_url "(null)" "ssh://hostname/repo" "../../../../subrepo" "ssh:subrepo"
+test_submodule_relative_url "(null)" "ssh://hostname/repo" "../../../../../subrepo" ".:subrepo"
 test_submodule_relative_url "(null)" "ssh://hostname:22/repo" "../subrepo" "ssh://hostname:22/subrepo"
 test_submodule_relative_url "(null)" "user@host:path/to/repo" "../subrepo" "user@host:path/to/subrepo"
 test_submodule_relative_url "(null)" "user@host:repo" "../subrepo" "user@host:subrepo"
+test_submodule_relative_url "(null)" "user@host:repo" "../../subrepo" ".:subrepo"
 
 test_expect_success 'match .gitmodules' '
 	test-tool path-utils is_dotgitmodules \
-- 
2.18.0.865.gffc8e1a3cd6