Test case should be added to enhance the test coverage

[slievrly]

Requirement:

Test case should be added to enhance the test coverage . Junit and mockito can be used as test framework.
Welcome everyone to join in，you can comment on the issue that you're interest with.

Project address

https://github.com/alibaba/fescar/projects/1

Issues

status	assignee	issues
		Add unit test to fescar-common module
		Add unit test to fescar-config module
	@xiajunhust	Add unit test to fescar-core module
		Add unit test to fescar-dubbo module
		Add unit test to fescar-rm-datasource module
		Add unit test to fescar-server module
	@tswstarplanet	Add unit test to fescar-spring module
		Add unit test to fescar-tm module

[gzlicanyi]

I didn't find the standard create table SQL statement in the documentation or the code, including undo_log, account_tbl, storage_tbl, and order_tbl, so please provide it, and not others who want to help must guess it from the code.

[slievrly]

It is included in the quickstart and will be added to the demo script later.

[slievrly]

UnitTest Must contain copyright