Frontend: Add a helpful validation message when masked variable value matches the name of an existing variable

Release notes

Problem to solve

When creating a new project or group variable, masked variables value can't match the name of an existing variable.

We show the same generic error that is unhelpful in resolving the problem.

The error just says This variable can't be masked, and doesn't explain why.

Proposal

When ✅ Masked is selected in the add variable modal:

1. When the value entered for a potential masked variable matches the name of an existing variable, show : Value cannot match the name of an existing predefined or custom CI/CD variable.
2. For all other error in the masked variable value field show: This variable can't be masked.

Implementation guide

backend

We need to look into what's happening while the validations are being ran 👇

• Ci::GroupVariable
• Ci::Maskable

To customize the error, we can use message attribute from ActiveRecord.

Intended users

• Sasha (Software Developer)
• Priyanka (Platform Engineer)

Feature Usage Metrics

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