Soft engineer video (21 ~ 25)-Software Testing

Software testing starts program testing, unit testing, and integration (integrated or assembled) testing, system testing, and acceptance (validation) testing after programmers code each module, parallel tests and manual tests. Some of the unit tests have started in the coding stage. Tests span the development and testing stages, and different personnel participate, testing itself is complex.

According to statistics, the test workload accounts for 40% to 50% of the total cost of software development.

From this figure, we can see the design concepts, principles, and technologies of software testing.

First, the concepts and principles.

Concept: activities (including code execution and manual activities) for checking and correcting software plans, software designs, and software code during software testing. Software Testing actually includes program testing. Software validation and program validation are their broad concepts, respectively. Here we need to add some software errors, mainly due to some functional errors and system errors. Functional errors are caused by incomplete design of the requirement analysis, and system errors are caused by overall design errors.

Test principles: (1) Identify the software to be tested as wrong before testing.

(2) determine the testing results of the tested software in advance

(3) try to avoid testing your own programs.

(4) reasonable and unreasonable input data should be taken into account during testing.

(5) The test should be based on the specification for software requirements.

(6) The new error to be clearly found is proportional to the existing error.

(7) The test is relative, and all tests cannot be exhausted. The test should be arranged according to manpower and material resources, and a good test case and test method should be selected.

(8) test cases should be reserved for test reports and subsequent repeated tests, and re-verify the error correction program.

Let's talk about the technology.

Purpose:

(1) the process of executing the program to discover errors in the program during testing;

(2) A good test scheme is a testing scheme that is very likely to discover errors not found so far;

(3) A successful test is a test where no errors have been found so far.

Test method: perform static analysis and dynamic analysis based on whether the test process is in the actual application environment.

The testing methods include static analysis and white box analysis and non-black box analysis ).

The white box method design test cases and test methods by analyzing the internal logic and execution routes of the program. The white box method is also called the logic-driven method. The black box method is a function-driven method. It only designs test cases based on I/O data conditions, regardless of the internal structure and path of the program. To put it bluntly, the white box method is transparent and can be operated internally. Because the black box method is not transparent, only external operations can be performed.

Design Test Scheme: statement coverage, decision coverage, and condition coverage are the key points.

Soft engineer video (21 ~ 25)-Software Testing