Charpter8 about unit testing, integration testing and system testing I understand.

General overview

unit testing, is to focus on the implementation of the source code for each program unit to test, to check whether each program module correctly implemented the specified function. The integration test assembles the tested modules, primarily testing the architecture of the software architectures associated with the design. System tests incorporate validated software into the actual operating environment, and are combined with other system components to test.

Unit Test (Unit testing)

unit testing, also known as module testing, is the smallest unit of software design - The program module, the correctness of the test work. The aim is to discover the various errors that may exist within each module. Unit testing requires the design of test cases from the internal structure of the program. Multiple modules can be individually unit tested in parallel.

Integration Testing (Integrated testing)

in general, on the basis of unit testing, all modules need to be assembled into a system according to the design requirements. The questions to consider at this point are:
– whether the data passing through the module interface will be lost when the modules are connected together;
– whether the function of one module can adversely affect the functionality of another module;
– each sub-function is combined to achieve the desired parent function;
– whether there is a problem with the global data structure;
– If the error of a single module accumulates, does it enlarge to an unacceptable degree.
during unit testing, integration testing can be carried out to identify and troubleshoot problems that may arise in connection with a module and ultimately constitute the required software system. subsystem integration testing is particularly called component testing, and it does the job of finding inconsistencies between the integrated subsystem and the system requirements specification.

Systems Testing (Systemtesting)

System testing, is to confirm the test software, as the entire computer system-based elements, and computer hardware, peripherals, some supporting software, data and personnel and other system elements together in the actual operating environment, the computer system to carry out a series of assembly testing and validation tests. The purpose of the system testing is to find out the definition of software and system is inconsistent or contradictory with the definition of system requirements.

Charpter8 about unit testing, integration testing and system testing I understand.