repo: Add OSTREE_BOOTID override envvar for debugging

It's useful for test cases to be able to influence this.

Conflicts:
	src/libostree/ostree-repo.c

Closes: #170
Approved by: jlebon

tests/basic-test.sh

@@ -400,11 +400,24 @@ echo "ok disable cache checkout"
 cd ${test_tmpdir}
 rm checkout-test2 -rf
 $OSTREE checkout test2 checkout-test2
-if env OSTREE_REPO_TEST_ERROR=pre-commit $OSTREE commit -b test2 -s '' $test_tmpdir/checkout-test2 2>err.txt; then
+date > checkout-test2/date.txt
+rm repo/tmp/* -rf
+export TEST_BOOTID=3072029c-8b10-60d1-d31b-8422eeff9b42
+if env OSTREE_REPO_TEST_ERROR=pre-commit OSTREE_BOOTID=${TEST_BOOTID} \
+       $OSTREE commit -b test2 -s '' $test_tmpdir/checkout-test2 2>err.txt; then
     assert_not_reached "Should have hit OSTREE_REPO_TEST_ERROR_PRE_COMMIT"
 fi
 assert_file_has_content err.txt OSTREE_REPO_TEST_ERROR_PRE_COMMIT
-echo "ok test error pre commit"
+found_staging=0
+for d in $(find repo/tmp/ -maxdepth 1 -type d); do
+    bn=$(basename $d)
+    if test ${bn##staging-} != ${bn}; then
+	assert_str_match "${bn}" "^staging-${TEST_BOOTID}-"
+	found_staging=1
+    fi
+done
+assert_streq "${found_staging}" 1
+echo "ok test error pre commit/bootid"
 
 # Whiteouts
 cd ${test_tmpdir}

tests/libtest.sh

@@ -86,6 +86,12 @@ assert_streq () {
     test "$1" = "$2" || (echo 1>&2 "$1 != $2"; exit 1)
 }
 
+assert_str_match () {
+    if ! echo "$1" | grep -E -q "$2"; then
+	(echo 1>&2 "$1 does not match regexp $2"; exit 1)
+    fi
+}
+
 assert_not_streq () {
     (! test "$1" = "$2") || (echo 1>&2 "$1 == $2"; exit 1)
 }