fix(searchbar): autocapitalize is initialized correctly

[liamdebeasi]

Issue number: resolves #29193

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What is the current behavior?

In an attempt to preserve backwards compatibility when adding autocapitalize to Searchbar, we used ! to indicate that the prop was never undefined. The autocapitalize on HTMLElement expects this value to be a string and never undefined.

For the purposes of the property on Searchbar, setting this prop to one of the accepted values would constitute a breaking change because it would override the default browser behavior (which we previously relied upon). As a result, we used ! to not set a default prop but inform TypeScript that this prop is always defined. This unintentionally made it so developers needed to define the autocapitalize property every time which is not what we want.

What is the new behavior?

• autocapitalize now defaults to the 'default' keyword. This is an internal keyword that is used to tell Ionic to not set the autocapitalize attribute on the inner input element and instead rely on the default browser behavior. This satisfies the HTMLElement requirement that autocapitalize is never undefined. In Ionic 8 this 'default' value will be replaced with 'off'.

Typescript currently sets the HTMLElement autocapitalize type to string which is why we can add a 'default' keyword here. There is some risk that if these type definitions change in the future that applications may encounter errors. However, changing this on the TypeScript side would itself be a breaking change. Additionally, we are moving away from 'default' in Ionic 8, so I think this is an acceptable amount of risk.

Does this introduce a breaking change?

• Yes
• No

Other information

Dev build: 7.8.2-dev.11711027016.13b2a920

Tested in a React starter app with Searchbar, and I verified this fix works.

[mapsandapps]

Makes sense. I tested it & it works 👍🏻