A source code that is difficult to understand and hard to change is known as Legacy Code. It can also be inherited code from the old software.
These are the following steps that need to be followed to improve legacy code.
The best way to understand the code is to create unit tests and characterization tests. Another method for testing the code is to use a quality code that analyzes the code by identifying problems.
This is the primary step that helps to understand the working code. The developer can make changes only if they have the required documents in hand. The output of the code should not be affected by the changes in the code.
It is very difficult and time consuming to rewrite the code from scratch. It is recommended to rewrite the code when it is necessary because it can also introduce new bugs.
To change the structure of code without changing the functionality is known as refactoring which is a better option than rewriting the code.
It is a good idea to make changes in different review cycles instead of doing them at once. This will also help in reviewing the code.
Collaborate with developers who have a better understanding of the code than you.
It is difficult to improve the quality of inherited code but make sure to add clean new code.
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