ComboBox in form submits input value rather than selected key

[LFDanLu]

🐛 Bug Report

Context: #1672

🤔 Expected Behavior

Not 100% sure but this is what I think might be correct:
ComboBox with allowCustomValue=false should probably submit its selected key on form submit. ComboBox with allowCustomValue=true should probably submit its input value on form submit if no selected key exists, otherwise submit its selected key.

EDIT: The above proposal has an issue since the user wouldn't be able to tell if it is a key or the input value being submitted

😯 Current Behavior

ComboBox always submits its input value on form submit

💁 Possible Solution

Possibly use HiddenSelect? Use something similar to HiddenSelect? Need to investigate

🔦 Context

💻 Code Sample

🌍 Your Environment

Software	Version(s)
react-spectrum
Browser
Operating System

🧢 Your Company/Team

🕷 Tracking Issue (optional)

[devongovett]

I think we could use an <input type="hidden" name={props.name} value={selectedKey}> rather than putting the name attribute on the <input type="text"> element. I guess only when allowsCustomValue is false? When if it's true though? Would you want to submit the selectedKey or the input value in the case the user did select on the of the items but custom values are allowed?

[tenphi]

@devongovett I would add that allowsCustomValue should allow selecting any value using defaultSelectedKey or selectedKey prop.
Currently, If a form has an initial value for Combobox and it's not on the list it's impossible to set it.
There is a defaultInputValue prop but it doesn't look good to use it for this scenario. Maybe I don't understand something here. I can create a separate ticket for that if you want.

IMHO Submitting the custom value is also critical.

[devongovett]

It sounds like what defaultInputValue is for, but feel free to open a separate discussion or issue about that if you're having trouble.