feat(NgxControlValueAccessor): add possibility to transform model values

[RobbyRabbitman]

#615

[gemini-code-assist]

Summary of Changes

Hello @RobbyRabbitman, I'm Gemini Code Assist¹! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request introduces a significant enhancement to the NgxControlValueAccessor by adding a transform function. This new capability allows developers to define custom logic for modifying model values as they are passed into the control, providing a powerful way to format, sanitize, or otherwise process data. The feature is supported by a new injection token for global configuration, a practical demonstration in the test application, and thorough documentation updates to ensure ease of adoption.

Highlights

• New transform function: Introduced a new transform function within NgxControlValueAccessor that allows intercepting and modifying incoming model values before they are set in the control.
• Configurable Transformation: The transform function can be set directly on the NgxControlValueAccessor instance or provided globally using the new provideCvaTransform utility, offering flexible configuration.
• Core Logic Integration: The initialValue and writeValue methods of NgxControlValueAccessor have been updated to apply the transform function, ensuring consistent value manipulation.
• Demonstration and Testing: A new CustomInputWithTransform component was added to the test application to visually demonstrate the feature, alongside comprehensive unit tests covering default behavior, instance-level, and provider-based transformations.
• Documentation Updates: Both English and Spanish documentation for NgxControlValueAccessor have been updated with a new section explaining how to use the transform functionality, including code examples.

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[gemini-code-assist]

Code Review

This pull request introduces a transform function to NgxControlValueAccessor, allowing for the transformation of incoming model values. The implementation is clean, and the core logic is well-tested. My review includes suggestions to improve the example code in the test application and to correct some issues in the documentation, such as a typo and an example that would fail with strict template checking.

[nx-cloud]

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☁️ Nx Cloud last updated this comment at 2025-12-15 02:32:25 UTC

[eneajaho]

@RobbyRabbitman looks like the CI doesn't pass. Can you look into it please? If we can make it pass we can merge I guess.