tests: Reset umask to 022 while creating test repository

In test-basic-root.sh we make assertions about the permissions
of files like baz/cow, which were created without an explicit chmod.
We can't do that unless we control the permissions.

For some reason the "debomatic" autobuilder used to do some Debian
archive rebuilds does the entire build including build-time tests
as uid 0 with umask 002, which broke those assertions. This seems
a weird thing to do, and I've opened a bug, but it also seems
reasonable to fix this test.

This also lets us remove a couple of existing workarounds for the
same issue.

Bug-Debian: https://bugs.debian.org/876138
Signed-off-by: Simon McVittie <smcv@collabora.com>

Closes: #1192
Approved by: cgwalters

tests/libtest.sh

@@ -150,6 +150,8 @@ setup_test_repository () {
     export OSTREE="${CMD_PREFIX} ostree ${ot_repo}"
 
     cd ${test_tmpdir}
+    local oldumask="$(umask)"
+    umask 022
     mkdir files
     cd files
     ot_files=`pwd`
@@ -172,6 +174,7 @@ setup_test_repository () {
     ln -s nonexistent baz/alink
     mkdir baz/another/
     echo x > baz/another/y
+    umask "${oldumask}"
 
     cd ${test_tmpdir}/files
     $OSTREE commit ${COMMIT_ARGS}  -b test2 -s "Test Commit 2" -m "Commit body second"

tests/test-basic-user.sh

@@ -34,11 +34,7 @@ setup_test_repository "bare-user"
 
 cd ${test_tmpdir}
 objpath_nonexec=$(ostree_file_path_to_object_path repo test2 baz/cow)
-# Sigh, umask
-touch testfile
-default_mode=$(stat -c '%a' testfile)
-rm testfile
-assert_file_has_mode ${objpath_nonexec} ${default_mode}
+assert_file_has_mode ${objpath_nonexec} 644
 objpath_ro=$(ostree_file_path_to_object_path repo test2 baz/cowro)
 assert_file_has_mode ${objpath_ro} 600
 objpath_exec=$(ostree_file_path_to_object_path repo test2 baz/deeper/ohyeahx)
@@ -48,7 +44,7 @@ echo "ok bare-user committed modes"
 rm test2-checkout -rf
 $OSTREE checkout -U -H test2 test2-checkout
 cd test2-checkout
-assert_file_has_mode baz/cow ${default_mode}
+assert_file_has_mode baz/cow 644
 assert_file_has_mode baz/cowro 600
 assert_file_has_mode baz/deeper/ohyeahx 755
 echo "ok bare-user checkout modes"