[Bug]: `PayButtonProps.onClick` type is incompatible with `ButtonProps.onClick` under strictFunctionTypes

[jmmarco]

Describe the bug

PayButtonProps interface in dist/es/index.d.ts (line 310) incorrectly extends ButtonProps. The onClick property narrows the event target from HTMLButtonElement | HTMLAnchorElement to just HTMLButtonElement, which TypeScript rejects under strictFunctionTypes (TS2430).

ButtonProps.onClick:

onClick?: (e: h.JSX.TargetedMouseEvent<HTMLButtonElement | HTMLAnchorElement>, callbacks?: { complete?: () => void }) => void;

PayButtonProps.onClick:

onClick?: (e: h.JSX.TargetedMouseEvent<HTMLButtonElement>) => void;

Under strictFunctionTypes, a child interface's method must accept at least the same parameter types as the parent. Since PayButtonProps.onClick only accepts HTMLButtonElement while ButtonProps.onClick accepts HTMLButtonElement | HTMLAnchorElement, TypeScript rejects the extension.

To Reproduce

• Install @adyen/adyen-web@6.31.1
• Configure tsconfig.json with "strict": true (which enables strictFunctionTypes) and without "skipLibCheck": true
• Import anything from @adyen/adyen-web in a TypeScript project
• Build the project (e.g. tsc or any build tool that runs the TypeScript compiler)
• See error: TS2430: Interface 'PayButtonProps' incorrectly extends interface 'ButtonProps'
  Expected behavior

PayButtonProps.onClick should have the same signature as ButtonProps.onClick to satisfy TS strict function type checking.

Screenshots

N/A — this is a type-checking error, not a visual bug.

Desktop (please complete the following information):
OS: macOS / Linux (any)
Browser: N/A (build-time error)
Version: @adyen/adyen-web@6.31.1, TypeScript 5.8.x

Smartphone (please complete the following information):

N/A — build-time error, not device-specific.

Additional context

This issue affects any project using strict: true in tsconfig.json without skipLibCheck: true
We are currently working around it with pnpm patch to align the onClick signature with the parent interface.

[sponglord]

@jmmarco - this will be fixed in the next release