📅  最后修改于: 2022-03-11 15:00:01.108000             🧑  作者: Mango
Top-Down testing begins with the system and
works its way down to the unit level.
• Bottom-up testing checks in the opposite
direction, unit level to interface to
overall system. Both have value but
bottom-up testing usually aids in discovering
defects earlier in the development cycle,
when the cost to fix errors is lower.