[
https://issues.apache.org/jira/browse/MYFACES-4658?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17833828#comment-17833828
]
Werner Punz edited comment on MYFACES-4658 at 4/4/24 6:14 AM:
--------------------------------------------------------------
Ok the discrepancy is indeed in the undefined handling, the spec states either
Here is the spec on this issue:
A varargs function that invokes an arbitrary number of scripts. If any script
in the chain returns false, the chain is short-circuited and subsequent scripts
are not invoked. Any number of scripts may specified after the {{event}}
argument.
boolean {{false}} if any scripts in the chain return {{{}false{}}}, otherwise
returns {{true}}
So the old code is correct the new code is wrong here!
I will make a fix for it including a test!
This test exposes the issue:
{code:java}
// code placeholder
it("chain must handle the true false return values correctly", function () {
let func1 = () => {
return true;
}
let func2 = () => {
return false;
}
let func3 = () => {
return undefined;
}
let func4 = () => {
return null;
}
let ret = faces.util.chain(this, {}, func1);
expect(ret).to.be.true;
ret = faces.util.chain(this, {}, func2);
expect(ret).to.be.false;
ret = faces.util.chain(this, {}, func3);
expect(ret).to.be.true;
ret = faces.util.chain(this, {}, func4);
expect(ret).to.be.true;
}) {code}
was (Author: werpu):
Ok the discrepancy is indeed in the undefined handling, the spec states either
Here is the spec on this issue:
A varargs function that invokes an arbitrary number of scripts. If any script
in the chain returns false, the chain is short-circuited and subsequent scripts
are not invoked. Any number of scripts may specified after the {{event}}
argument.
boolean {{false}} if any scripts in the chain return {{{}false{}}}, otherwise
returns {{true}}
{{}}
So the old code is correct the new code is wrong here!
I will make a fix for it including a test!
This test exposes the issue:
{code:java}
// code placeholder
it("chain must handle the true false return values correctly", function () {
let func1 = () => {
return true;
}
let func2 = () => {
return false;
}
let func3 = () => {
return undefined;
}
let func4 = () => {
return null;
}
let ret = faces.util.chain(this, {}, func1);
expect(ret).to.be.true;
ret = faces.util.chain(this, {}, func2);
expect(ret).to.be.false;
ret = faces.util.chain(this, {}, func3);
expect(ret).to.be.true;
ret = faces.util.chain(this, {}, func4);
expect(ret).to.be.true;
}) {code}
> faces.util.chain behavior changed
> ---------------------------------
>
> Key: MYFACES-4658
> URL: https://issues.apache.org/jira/browse/MYFACES-4658
> Project: MyFaces Core
> Issue Type: Bug
> Affects Versions: 4.0.2
> Reporter: Volodymyr Siedlecki
> Assignee: Werner Punz
> Priority: Major
>
> Given the following generated HTML, an alert will occur. If you click OK, it
> will perform an action on a backing bean. However, if you cancel, it should
> not.
> {code:java}
> <input type="submit" value="Test" onclick="return faces.util.chain(this,
> event,function(event){return confirm('Please Confirm');});">{code}
> On Faces 3.0, if cancel is pressed, then the backing bean is not invoked. On
> Faces 4.0, however, pressing cancel *does* invoke the bean.
> Faces 3.0:
> jsf.util.chain snippet:
> {noformat}
> if (FUNC == typeof arguments[cnt]) {
> ret = arguments[cnt].call(source, event);
> } else {
> //either a function or a string can be passed in case of a
> string we have to wrap it into another function
> ret = new Function("event", arguments[cnt]).call(source,
> event);
> }
> //now if one function returns false in between we stop the
> execution of the cycle
> //here, note we do a strong comparison here to avoid constructs
> like 'false' or null triggering
> if (ret === false /*undefined check implicitly done here by using
> a strong compare*/) {
> return false;
> }
> }{noformat}
> Faces 4.0:
> {noformat}
> function chain(source, event, ...funcs) {
> // we can use our lazy stream each functionality to run our chain
> here.
> // by passing a boolean as return value into the onElem call
> // we can stop early at the first false, just like the spec requests
> let ret;
> funcs.every(func => {
> let returnVal = resolveAndExecute(source, event, func);
> if (returnVal !== false) {
> ret = returnVal;
> }
> return returnVal !== false;
> });
> return ret;
> }{noformat}
> It looks like conditions changed here? "ret === false" became "returnVal !==
> false" ? If cancel is pressed, false is returned, which means the chain
> function returns false in 3.0. In faces 4.0, ret is never set (due to the
> new condition), so undefined (ret) is returned now instead.
--
This message was sent by Atlassian Jira
(v8.20.10#820010)
