t/: migrate helper/test-oidtree.c to unit-tests/t-oidtree.c

helper/test-oidtree.c along with t0069-oidtree.sh test the oidtree.h
library, which is a wrapper around crit-bit tree. Migrate them to
the unit testing framework for better debugging and runtime
performance. Along with the migration, add an extra check for
oidtree_each() test, which showcases how multiple expected matches can
be given to check_each() helper.

To achieve this, introduce a new library called 'lib-oid.h'
exclusively for the unit tests to use. It currently mainly includes
utility to generate object_id from an arbitrary hex string
(i.e. '12a' -> '12a0000000000000000000000000000000000000'). This also
handles the hash algo selection based on GIT_TEST_DEFAULT_HASH.
This library will also be helpful when we port other unit tests such
as oid-array, oidset etc.

Helped-by: Junio C Hamano <gitster@pobox.com>
Mentored-by: Christian Couder <chriscool@tuxfamily.org>
Mentored-by: Kaartic Sivaraam <kaartic.sivaraam@gmail.com>
Signed-off-by: Ghanshyam Thakkar <shyamthakkar001@gmail.com>
[jc: small fixlets squashed in]
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 17 insertions, 0 deletions

diff --git a/t/unit-tests/lib-oid.h b/t/unit-tests/lib-oid.h
new file mode 100644
index 0000000000..bfde639190
--- /dev/null
+++ b/t/unit-tests/lib-oid.h
@@ -0,0 +1,17 @@
+#ifndef LIB_OID_H
+#define LIB_OID_H
+
+#include "hash-ll.h"
+
+/*
+ * Convert arbitrary hex string to object_id.
+ * For example, passing "abc12" will generate
+ * "abc1200000000000000000000000000000000000" hex of length 40 for SHA-1 and
+ * create object_id with that.
+ * WARNING: passing a string of length more than the hexsz of respective hash
+ * algo is not allowed. The hash algo is decided based on GIT_TEST_DEFAULT_HASH
+ * environment variable.
+ */
+int get_oid_arbitrary_hex(const char *s, struct object_id *oid);
+
+#endif /* LIB_OID_H */