What?

It fixes an issue with the apiFetch, which is not parsing the response error when using the fetchAllMiddleware.

Notice that it's not ready to be merged because it could cause backward compatibility problems. I didn't have any good idea so far to keep it working with existing implementations parsing the error manually for this case. Any ideas?

Why?

When using the apiFetch, we need to parse the error JSON manually if we have a per_page=-1 in the path. See the problem with more details by running:

apiFetch( { path: '/wp/v2/anything?per_page=-1' } )
	.then( console.log )
	.catch( ( err ) => {
		console.log(
			'See that the error is not parsed when using per_page=-1',
			err
		);
	} );

apiFetch( { path: '/wp/v2/anything?per_page=-1' } )
	.then( console.log )
	.catch( ( err ) => err.json() )
	.then( ( err ) => {
		console.log(
			'See that the error is parsed when we do it manually',
			err
		);
	} );

apiFetch( { path: '/wp/v2/anything' } )
	.then( console.log )
	.catch( ( err ) => {
		console.log(
			'See that the error is parsed when not using the per_page=-1',
			err
		);
	} );

By default, it shouldn't be needed, because the parse option is true and should parse the JSON for us.

How?

It was skipping the parse in case of error because it's forcing parse: false and parsing it later only in case of success. It fixes it by catching the error and parsing it too through the parseAndThrowError.

Testing Instructions

Use the following snippet, and make sure the error is parsed.

apiFetch( { path: '/wp/v2/anything?per_page=-1' } )
	.then( console.log )
	.catch( console.log );