Some problems during form completion result in exceptions during form filling or on form refilling but not on form validation

[lognaturel]

Software versions

All versions

Problem description

A calculation such as decimal-date-time(concat( /data/year ,"-01-01")) can result in an exception if /date/year is left blank or otherwise invalid. However, that exception doesn't occur on finalization so a form can be submitted with a bad value.

This is really a form design issue and /data/year should have a constraint on it. However, the form probably should not be finalizable if the value can't be used. I think there are similar cases with trying to access values in a repeat without specifying a repeat instance.

I'm not 100% sure this is a JavaRosa issue. It might also have to do with how Collect catches JR exceptions.

Steps to reproduce the problem

In a form like the following, clear out the year value:

<?xml version="1.0"?>
<h:html xmlns="http://www.w3.org/2002/xforms">
	<h:head>
		<h:title>validate</h:title>
		<model>
			<instance>
				<data id="validate">
					<year>2019</year>
					<result/>
				</data>
			</instance>
			<bind nodeset="/data/year" type="int"/>
			<bind calculate="decimal-date-time(concat( /data/year ,&quot;-01-01&quot;))" nodeset="/data/result" type="string"/>
		</model>
	</h:head>
	<h:body>
		<input ref="/data/year">
			<label>year</label>
		</input>
	</h:body>
</h:html>

Expected behavior

Forms that throw exceptions during form filling can't be finalized.

CC @seadowg