Hard-coding a URI makes it difficult to test a program for a variety of reasons:
- path literals are not always portable across operating systems
- a given absolute path may not exist in a specific test environment
- a specified Internet URL may not be available when executing the tests
- production environment filesystems usually differ from the development environment
In addition, hard-coded URIs can contain sensitive information, like IP addresses, and they should not be stored in the code.
For all those reasons, a URI should never be hard coded. Instead, it should be replaced by a customizable parameter.
Further, even if the elements of a URI are obtained dynamically, portability can still be limited if the path delimiters are hard-coded.
This rule raises an issue when URIs or path delimiters are hard-coded.