useFormState: MPA submissions to a different page

[acdlite]

The permalink option of useFormState controls which page the form is submitted to during an MPA form submission (i.e. a submission that happens before hydration, or when JS is disabled). If the same useFormState appears on the resulting page, and the permalink option matches, it should receive the form state from the submission despite the fact that the keypaths do not match.

So the logic for whether a form state instance is considered a match is:

• Both instances must be passed the same action signature
• If a permalink is provided, the permalinks must match.
• If a permalink is not provided, the keypaths must match.

Currently, if there are multiple matching useFormStates, they will all match and receive the form state. We should probably only match the first one, and/or warn when this happens. I've left this as a TODO for now, pending further discussion.

[react-sizebot]

Comparing: 95c9554...a3e39ce

Critical size changes

Includes critical production bundles, as well as any change greater than 2%:

Name	+/-	Base	Current	+/- gzip	Base gzip	Current gzip
oss-stable/react-dom/cjs/react-dom.production.min.js	=	166.62 kB	166.62 kB	=	52.13 kB	52.13 kB
oss-experimental/react-dom/cjs/react-dom.production.min.js	=	176.05 kB	176.05 kB	=	54.97 kB	54.96 kB
facebook-www/ReactDOM-prod.classic.js	=	571.73 kB	571.73 kB	=	100.64 kB	100.64 kB
facebook-www/ReactDOM-prod.modern.js	=	555.46 kB	555.46 kB	=	97.75 kB	97.75 kB

Significant size changes

Includes any change greater than 0.2%:

Expand to show

Name	+/-	Base	Current	+/- gzip	Base gzip	Current gzip
oss-experimental/react-server/cjs/react-server.development.js	+0.56%	169.38 kB	170.32 kB	+0.55%	41.60 kB	41.83 kB
oss-experimental/react-server/cjs/react-server.production.min.js	+0.32%	29.88 kB	29.98 kB	+0.32%	9.90 kB	9.93 kB
facebook-www/ReactDOMServerStreaming-dev.modern.js	+0.29%	350.94 kB	351.97 kB	+0.33%	78.21 kB	78.46 kB
facebook-www/ReactDOMServer-dev.modern.js	+0.29%	355.75 kB	356.78 kB	+0.32%	79.36 kB	79.61 kB
facebook-www/ReactDOMServer-dev.classic.js	+0.28%	363.17 kB	364.20 kB	+0.31%	81.00 kB	81.25 kB
oss-experimental/react-dom/cjs/react-dom-server.bun.development.js	+0.26%	360.59 kB	361.53 kB	+0.27%	81.39 kB	81.60 kB
oss-experimental/react-dom/cjs/react-dom-server-legacy.browser.development.js	+0.26%	363.09 kB	364.03 kB	+0.27%	81.82 kB	82.04 kB
oss-experimental/react-dom/umd/react-dom-server-legacy.browser.development.js	+0.26%	380.51 kB	381.49 kB	+0.27%	82.68 kB	82.91 kB
oss-experimental/react-dom/cjs/react-dom-server-legacy.node.development.js	+0.26%	365.00 kB	365.94 kB	+0.26%	82.27 kB	82.49 kB
oss-experimental/react-dom/cjs/react-dom-server.browser.development.js	+0.25%	369.22 kB	370.16 kB	+0.26%	82.55 kB	82.76 kB
oss-experimental/react-dom/cjs/react-dom-server.edge.development.js	+0.25%	369.63 kB	370.57 kB	+0.26%	82.67 kB	82.89 kB
oss-experimental/react-dom/cjs/react-dom-server.node.development.js	+0.25%	370.51 kB	371.45 kB	+0.26%	82.87 kB	83.08 kB
oss-experimental/react-dom/umd/react-dom-server.browser.development.js	+0.25%	386.93 kB	387.91 kB	+0.25%	83.44 kB	83.65 kB
facebook-www/ReactDOMServer-prod.modern.js	+0.24%	157.61 kB	157.99 kB	+0.15%	28.78 kB	28.83 kB
facebook-www/ReactDOMServer-prod.classic.js	+0.24%	158.28 kB	158.66 kB	+0.13%	28.98 kB	29.02 kB
facebook-www/ReactDOMServerStreaming-prod.modern.js	+0.24%	159.70 kB	160.09 kB	+0.15%	29.73 kB	29.77 kB

Generated by 🚫 dangerJS against a3e39ce

[sebmarkbage]

Maybe permalink isn't the quite the right terminology for this although it's usually the same thing but it doesn't have to be a permanent link or even easily consumable. Maybe canonicalURL (like <link rel="canonical">) is also somewhat similar. It really means a URL that represents this form in isolation (and not in a list or in an expansion/fly out).