fix(ts-interface-generator): support classes inheriting from generic base classes

[CLVNSwan]

Problem

When a class inherits from a generic base class (e.g., MyBaseClass<T>), the @ui5/ts-interface-generator skips the class entirely and does not generate a .gen.d.ts file.

Root Cause

TypeScript's type.isClassOrInterface() returns false for instantiated generic types. For example:

• Control → isClassOrInterface() returns true ✅
• GenericControl<string> → isClassOrInterface() returns false ❌

The generator's getInterestingBaseClass() and getInterestingBaseSettingsClass() functions currently return early when isClassOrInterface() is false, causing all classes inheriting from generic base classes to be skipped.

Solution

For instantiated generic types, TypeScript stores the original generic class definition in the target property of the TypeReference. This fix checks for this property and uses it to continue the inheritance chain resolution.

Reproduction Example

import Control from "sap/ui/core/Control";
import type { MetadataOptions } from "sap/ui/core/Element";

// Generic base class extending a UI5 class
class GenericControl<T> extends Control {
  static readonly metadata: MetadataOptions = {
    properties: {
      value: { type: "object" }
    }
  };
}

/**
 * @namespace my.app.control
 */
export default class MyControl extends GenericControl<string> {
  static readonly metadata: MetadataOptions = {
    properties: {
      name: { type: "string", defaultValue: "" }
    }
  };
}

Before this fix: No MyControl.gen.d.ts is generated, no accessor methods like getName() / setName() are typed.

After this fix: MyControl.gen.d.ts is generated correctly with all typed accessor methods.

Changes

• getInterestingBaseClass(): When isClassOrInterface() returns false, check if type.target exists and is a class/interface, then use that for inheritance resolution.
• getInterestingBaseSettingsClass(): Same approach - when symbol is null, check type.target and recursively resolve.

Testing

Tested with a custom UI5 library containing generic base classes. All subclasses now correctly generate .gen.d.ts files.

[cla-assistant]

All committers have signed the CLA.

[Copilot]

Pull request overview

This PR fixes @ui5/ts-interface-generator skipping classes that extend an instantiated generic base class (e.g. GenericBase<string>) by continuing inheritance resolution via ts.TypeReference.target.

Changes:

• Extend getInterestingBaseClass() to unwrap instantiated generic TypeReferences via .target when type.isClassOrInterface() is false.
• Extend getInterestingBaseSettingsClass() to retry resolution via .target when type.getSymbol() is unavailable for instantiated generic types.

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[akudev]

@CLVNSwan what is your use-case for a GenericControl<T>?

[akudev]

@CLVNSwan this seems to not pass CI: https://github.com/UI5/typescript/actions/runs/25680623026/job/75390791849
Have you run yarn ci locally?

CI failure