Chdir changes the current working directory to the named directory.

CombinedPaths collects all PATH strings from the provided environment variables, in the form of 'PATH=<path>', and combines them into a single PATH string, also in the form of 'PATH=<collected paths>'.

Create creates or truncates the named file.

Create creates or truncates the named file.

Setenv calls t.Setenv with the provided key and value.

Setenvs sets the provided environment variables keys with their corresponding values.

Unsetenv unsets the environment variable, which is later restored during test Cleanup.

Unsetenvs unsets the provided environment variables, which is later restored during test Cleanup.