`add -s` command accepts invalid phone number format.

[thony-ui]

• Description:
  The add -s command accepts invalid phone number format. It was not stated in the user guide which country the application is designed for and thus the users are not sure which phone number format is accepted or not.

• Steps to Reproduce:

  1. Enter the command add -s n/John Do p/111 e/johnd@example.com com/companyA t/friends t/owesMoney pro/rice pro/bread

• Expected Result:
  Assuming the context is in Singapore, the phone number should only start with "8", "9", "6", "3" and be 8 digits long. Hence this command should be rejected.

• Actual Result:
  The command was executed successfully and the supplier was added to the database.

[nus-se-script]

Team's Response

Thank you for pointing out this issue. As you have mentioned our target users are not restricted to Singapore but small convenience store owners in general. The valid phone numbers that we allow is intended since many international numbers start with different digits and are of varying lengths.

Furthermore, in our UG we have specifically given the restrictions for the phone number that the user can enter so that they have no confusion as seen below:

Items for the Tester to Verify

:question: Issue response

Team chose [response.Rejected]

• [x] I disagree

Reason for disagreement: Even if the UG mentions that the application allows longer phone numbers, this is still a flaw. Based on research, the longest phone number in the world is 17 digits, as highlighted here. Allowing users to input a phone number longer than this without an appropriate error message is clearly an oversight. Keying in a number longer than 17 digits is almost certainly a mistake, and without validation, it could lead to inaccurate or invalid data being stored. The absence of an error message for such inputs compromises the application's reliability and usability, as users are left unaware that they have entered something unreasonable. Adding validation for this case would prevent potential errors.

---