Programmer growth Chapter 8: do a good job of testing

In most companies , After the programmer finishes the function , There will be special test department students to conduct professional tests . In fact, many large companies didn't have testing posts in the early days , It's as more and more skills are tested , The requirement for ability is higher and higher , Only then did I have a testing position .

But I think even if the company has test engineers , As R & D personnel , You should also be able to test . Know some test thinking . Think about it , If in the team , Every time you submit code , Feedback bug most . Is it also shameless ？

I think the following points , Every R & D personnel should think and practice .

One 、 Thinking in abnormal situations . Under the inertial thinking , When testing a function, we will input it according to the normal value . For example, withdrawal function . We will test a positive number . The abnormal situation is , Let's enter a 0 Or a negative number or non number , How will the software feed back ？ Whether the front end is controlled ？ Is there any control at the back end . It is only right to control both .

Two 、 Thinking about extreme abnormal situations , For example, the weak network environment , Will cause the request to fail , Whether reconnection is required ？ What is the mechanism of reconnection ？ Another example is that the input item is an array , Normally, we will pass in an array , Non array condition , We do a good job of handling , Also consider extreme situations , For example, pass in a very large array , The program will jam and collapse , Or how ？ This needs to be considered when writing code .

3、 ... and 、 Do unit test well . Unit testing is used for a module 、 A function or a class to test correctness . Generally, we will run unit tests through program Automation . If something goes wrong , We usually run unit tests first , After this passes , To find the cause of the problem .

Four 、 Do function test well . After running the unit test , Then do the function test . Because even if each independent module is normal , But there are still many situations that will cause problems . Every time you modify, you need to run through the functions you have done . In general, we are testing in real / In the test environment , The situation of simulated data test is not .

5、 ... and 、 Have your own problem base , Put all the things you have met bug And solutions are put into the problem library . It would be better if the company has a problem base , without , You can also advise your supervisor to set up . With this problem base , Later, the same type of problems , Can quickly find solutions , Avoid the same problem , We need to solve it from the beginning every time .

In fact, testing is sometimes more difficult than writing code , Because when you write, you think and code according to normal logic , But after the test, you need to think from different scenes , This critical thinking 、 Logical thinking 、 The ability to think systematically , But it's worth investing in exercise .