Add unit tests for rmgrdesc

Co-authored-by: NDavid Kimura <dkimura@pivotal.io>

src/backend/access/rmgrdesc/test/Makefile

+subdir=src/backend/access/rmgrdesc
+top_builddir=../../../../..
+include $(top_builddir)/src/Makefile.global
+
+TARGETS=xactdesc
+
+include $(top_builddir)/src/backend/mock.mk

src/backend/access/rmgrdesc/test/xactdesc_test.c

+#include <stdarg.h>
+#include <stddef.h>
+#include <setjmp.h>
+#include "cmockery.h"
+
+#include "postgres.h"
+
+#include "utils/memutils.h"
+#include "access/xlog.h"
+#include "pgtime.h"
+
+/* Actual function body */
+#include "../xactdesc.c"
+
+static void
+test_xactdescprepareCommit(void **state)
+{
+	StringInfo buf = makeStringInfo();
+	XLogRecord *rec = palloc(SizeOfXLogRecord + MAXALIGN(sizeof(TwoPhaseFileHeader)));
+
+	rec->xl_info = XLOG_XACT_PREPARE;
+	TwoPhaseFileHeader* tpfh = (TwoPhaseFileHeader*) XLogRecGetData(rec);
+
+	tpfh->prepared_at = 617826371830030;
+	strcpy(tpfh->gid, "4242424242-0000000042");
+	tpfh->tablespace_oid_to_delete_on_commit = 42;
+	tpfh->tablespace_oid_to_delete_on_abort = InvalidOid;
+
+	xact_desc(buf, rec);
+
+	assert_string_equal("prepare: at = 2019-07-30 18:26:11.83003+00; gid = 4242424242-0000000042; tablespace_oid_to_delete_on_commit = 42", buf->data);
+}
+
+static void
+test_xactdescprepareAbort(void **state)
+{
+	StringInfo buf = makeStringInfo();
+	XLogRecord *rec = palloc(SizeOfXLogRecord + MAXALIGN(sizeof(TwoPhaseFileHeader)));
+
+	rec->xl_info = XLOG_XACT_PREPARE;
+	TwoPhaseFileHeader* tpfh = (TwoPhaseFileHeader*) XLogRecGetData(rec);
+
+	tpfh->prepared_at = 617826371830030;
+	strcpy(tpfh->gid, "4242424242-0000000042");
+	tpfh->tablespace_oid_to_delete_on_commit = InvalidOid;
+	tpfh->tablespace_oid_to_delete_on_abort = 42;
+
+	xact_desc(buf, rec);
+
+	assert_string_equal("prepare: at = 2019-07-30 18:26:11.83003+00; gid = 4242424242-0000000042; tablespace_oid_to_delete_on_abort = 42", buf->data);
+}
+
+static void
+test_xactdescprepareNone(void **state)
+{
+	StringInfo buf = makeStringInfo();
+	XLogRecord *rec = palloc(SizeOfXLogRecord + MAXALIGN(sizeof(TwoPhaseFileHeader)));
+
+	rec->xl_info = XLOG_XACT_PREPARE;
+	TwoPhaseFileHeader* tpfh = (TwoPhaseFileHeader*) XLogRecGetData(rec);
+
+	tpfh->prepared_at = 617826371830030;
+	strcpy(tpfh->gid, "4242424242-0000000042");
+	tpfh->tablespace_oid_to_delete_on_commit = InvalidOid;
+	tpfh->tablespace_oid_to_delete_on_abort = InvalidOid;
+
+	xact_desc(buf, rec);
+
+	assert_string_equal("prepare: at = 2019-07-30 18:26:11.83003+00; gid = 4242424242-0000000042", buf->data);
+}
+
+int
+main(int argc, char* argv[])
+{
+	cmockery_parse_arguments(argc, argv);
+
+	MemoryContextInit();
+	pg_timezone_initialize();
+
+	const UnitTest tests[] = {
+		unit_test(test_xactdescprepareCommit),
+		unit_test(test_xactdescprepareAbort),
+		unit_test(test_xactdescprepareNone)
+	};
+
+	return run_tests(tests);
+}