[jira] [Commented] (VELOCITY-911) Incorrect evaluation of IF-Directive for objects with isEmpty-method
[ https://issues.apache.org/jira/browse/VELOCITY-911?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel=16808426#comment-16808426 ] M. Luppi commented on VELOCITY-911: --- Thanks for your reply, [~claude]. I was aware of the _directive.if.emptycheck_-property that gives me the behavior of version 1.7. However, we would like to use this new feature in our project. My suggestion is to extend and correct the documentation to reflect the actual behavior more accurately. This way the users get a clear reference and knows exactly how the engine evaluates objects in a boolean context. In fact, using such logic on custom objects is a (yet undocumented) feature and worth addressing. Maybe a remark concerning visibility (method needs to be public) would be appropriate as well. Maybe something along the lines of in the user guide ([http://velocity.apache.org/engine/2.1/user-guide.html#if-elseif-else]): {panel} * ... * $foo is an object with a getAsBoolean() method which evaluates to a true value * $foo is an object with an isEmpty() method which evaluates to a true value * $foo is an object without a getAsBoolean() or isEmpty() method which is not null{panel} I do not know about the precedence of getAsBoolean() and isEmpty() and whether getAsBoolean()==false would preemptively stop evaluation. So the above might not be correct and could need adjustment. In the configuration page ([https://velocity.apache.org/engine/2.1/configuration.html#if-directive]) this could look like this: {panel} * ... * return whether isEmpty() is false (covers String, all Collection classes and other objects that have a public isEmpty() method). * ...{panel} Of course the cases with length() and size() should also be adopted if necessary. The getAsBoolean() is already well-documented there. [~sdumitriu]: I do not understand why this issue was closed as "not a problem" at this point, unless I need to raise a new issue to address the documentation itself. > Incorrect evaluation of IF-Directive for objects with isEmpty-method > > > Key: VELOCITY-911 > URL: https://issues.apache.org/jira/browse/VELOCITY-911 > Project: Velocity > Issue Type: Bug >Affects Versions: 2.0, 2.1 >Reporter: M. Luppi >Assignee: Claude Brisson >Priority: Major > Attachments: VelocityIsEmptyBugMCVE.java, mcve-project.zip, > template.vm > > > With Velocity 2.0 the logic of evaluation for IF-Directives changed and now > uses an extended approach to determine whether it is true. This bug report > only refers to the case where $foo is an +object+. The documentation for 2.0 > and 2.1 state as follows: > {quote}The variable $foo is evaluated to determine whether it is true, which > will happen under one of those circumstances: [...] > $foo is an object (other than a string, a number or a collection) which is > not null > _Source: > [http://velocity.apache.org/engine/2.0/user-guide.html#if-elseif-else|http://velocity.apache.org/engine/2.0/user-guide.html#if-elseif-else]_ > {quote} > After a long debugging session I have found that objects with a public > isEmpty-method are not being handled according to the documentation cited > above. Thereby, such objects are evaluated as false if there is an > isEmpty-method that returns false. The correct evaluation result according to > the documentation should be true since the object is not null and not a > string, a number or a collection. > It gets even more confusing when we take access modifiers into account. If > the access of the isEmpty-method is not public, the behaviour is as it should > be. When we make it public, however, the above explained bug occurs in > version 2.0 as well as 2.1. > See the attached classes and the template or the whole project of the MCVE > (minimal, complete, and verifiable example) as ZIP. > _The output of the test is as follows:_ > {code:java} > null object > --- > [ OK ] Expected. > non-null object with isEmpty-method (public) > > isEmpty evaluates to true > [FAIL] Not expected since object is not null. > isEmpty evaluates to false > [ OK ] Expected. > non-null object with isEmpty-method (package-private) > - > isEmpty evaluates to true > [ OK ] Expected. > isEmpty evaluates to false > [ OK ] Expected. > {code} -- This message was sent by Atlassian JIRA (v7.6.3#76005) - To unsubscribe, e-mail: dev-unsubscr...@velocity.apache.org For additional commands, e-mail: dev-h...@velocity.apache.org
[jira] [Updated] (VELOCITY-911) Incorrect evaluation of IF-Directive for objects with isEmpty-method
[ https://issues.apache.org/jira/browse/VELOCITY-911?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ] M. Luppi updated VELOCITY-911: -- Description: With Velocity 2.0 the logic of evaluation for IF-Directives changed and now uses an extended approach to determine whether it is true. This bug report only refers to the case where $foo is an +object+. The documentation for 2.0 and 2.1 state as follows: {quote}The variable $foo is evaluated to determine whether it is true, which will happen under one of those circumstances: [...] $foo is an object (other than a string, a number or a collection) which is not null _Source: [http://velocity.apache.org/engine/2.0/user-guide.html#if-elseif-else|http://velocity.apache.org/engine/2.0/user-guide.html#if-elseif-else]_ {quote} After a long debugging session I have found that objects with a public isEmpty-method are not being handled according to the documentation cited above. Thereby, such objects are evaluated as false if there is an isEmpty-method that returns false. The correct evaluation result according to the documentation should be true since the object is not null and not a string, a number or a collection. It gets even more confusing when we take access modifiers into account. If the access of the isEmpty-method is not public, the behaviour is as it should be. When we make it public, however, the above explained bug occurs in version 2.0 as well as 2.1. See the attached classes and the template or the whole project of the MCVE (minimal, complete, and verifiable example) as ZIP. _The output of the test is as follows:_ {code:java} null object --- [ OK ] Expected. non-null object with isEmpty-method (public) isEmpty evaluates to true [FAIL] Not expected since object is not null. isEmpty evaluates to false [ OK ] Expected. non-null object with isEmpty-method (package-private) - isEmpty evaluates to true [ OK ] Expected. isEmpty evaluates to false [ OK ] Expected. {code} was: With Velocity 2.0 the logic of evaluation for IF-Directives changed and now uses an extended approach to determine whether it is true. This bug report only refers to the case where $foo is an +object+. The documentation for 2.0 and 2.1 state as follows: {quote}The variable $foo is evaluated to determine whether it is true, which will happen under one of those circumstances: [...] $foo is an object (other than a string, a number or a collection) which is not null _Source: [http://velocity.apache.org/engine/2.0/user-guide.html#if-elseif-else|http://velocity.apache.org/engine/2.0/user-guide.html#if-elseif-else_]_ {quote} After a long debugging session I have found that objects with a public isEmpty-method are not being handled according to the documentation cited above. Thereby, such objects are evaluated as false if there is an isEmpty-method that returns false. The correct evaluation result according to the documentation should be true since the object is not null and not a string, a number or a collection. It gets even more confusing when we take access modifiers into account. If the access of the isEmpty-method is not public, the behaviour is as it should be. When we make it public, however, the above explained bug occurs in version 2.0 as well as 2.1. See the attached classes and the template or the whole project of the MCVE (minimal, complete, and verifiable example) as ZIP. _The output of the test is as follows:_ {code:java} null object --- [ OK ] Expected. non-null object with isEmpty-method (public) isEmpty evaluates to true [FAIL] Not expected since object is not null. isEmpty evaluates to false [ OK ] Expected. non-null object with isEmpty-method (package-private) - isEmpty evaluates to true [ OK ] Expected. isEmpty evaluates to false [ OK ] Expected. {code} > Incorrect evaluation of IF-Directive for objects with isEmpty-method > > > Key: VELOCITY-911 > URL: https://issues.apache.org/jira/browse/VELOCITY-911 > Project: Velocity > Issue Type: Bug >Affects Versions: 2.0, 2.1 >Reporter: M. Luppi >Priority: Major > Attachments: VelocityIsEmptyBugMCVE.java, mcve-project.zip, > template.vm > > > With Velocity 2.0 the logic of evaluation for IF-Directives changed and now > uses an extended approach to determine whether it is true. This bug report > only refers to the case where $foo is an +object+. The documentation for 2.0 > and 2.1 state as follows: > {quote}The variable $foo is evaluated to determine whether it is true, which > will happen under one of those circumstances: [...] > $foo is an object (other
[jira] [Updated] (VELOCITY-911) Incorrect evaluation of IF-Directive for objects with isEmpty-method
[ https://issues.apache.org/jira/browse/VELOCITY-911?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ] M. Luppi updated VELOCITY-911: -- Description: With Velocity 2.0 the logic of evaluation for IF-Directives changed and now uses an extended approach to determine whether it is true. This bug report only refers to the case where $foo is an +object+. The documentation for 2.0 and 2.1 state as follows: {quote}The variable $foo is evaluated to determine whether it is true, which will happen under one of those circumstances: [...] $foo is an object (other than a string, a number or a collection) which is not null _Source: [http://velocity.apache.org/engine/2.0/user-guide.html#if-elseif-else|http://velocity.apache.org/engine/2.0/user-guide.html#if-elseif-else_]_ {quote} After a long debugging session I have found that objects with a public isEmpty-method are not being handled according to the documentation cited above. Thereby, such objects are evaluated as false if there is an isEmpty-method that returns false. The correct evaluation result according to the documentation should be true since the object is not null and not a string, a number or a collection. It gets even more confusing when we take access modifiers into account. If the access of the isEmpty-method is not public, the behaviour is as it should be. When we make it public, however, the above explained bug occurs in version 2.0 as well as 2.1. See the attached classes and the template or the whole project of the MCVE (minimal, complete, and verifiable example) as ZIP. _The output of the test is as follows:_ {code:java} null object --- [ OK ] Expected. non-null object with isEmpty-method (public) isEmpty evaluates to true [FAIL] Not expected since object is not null. isEmpty evaluates to false [ OK ] Expected. non-null object with isEmpty-method (package-private) - isEmpty evaluates to true [ OK ] Expected. isEmpty evaluates to false [ OK ] Expected. {code} was: With Velocity 2.0 the logic of evaluation for IF-Directives changed and now uses an extended approach to determine whether it is true. This bug report only refers to the case where $foo is an +object+. The documentation for 2.0 and 2.1 state as follows: {quote}The variable $foo is evaluated to determine whether it is true, which will happen under one of those circumstances: [...] $foo is an object (other than a string, a number or a collection) which is not null _Source: http://velocity.apache.org/engine/2.0/user-guide.html#if-elseif-else_ {quote} After a long debugging session I have found that objects with a public isEmpty-method are not being handled according to the documentation cited above. Thereby, such objects are evaluated as false if there is an isEmpty-method that returns false. The correct evaluation result according to the documentation should be true since the object is not null and not a string, a number or a collection. It gets even more confusing when we take access modifiers into account. If the access of the isEmpty-method is not public, the behaviour is as it should be. When we make it public, however, the above explained bug occurs in version 2.0 as well as 2.1. See the attached classes and the template or the whole project of the MCVE (minimal, complete, and verifiable example) as ZIP. The output of the test is as follows: {code:java} null object --- [ OK ] Expected. non-null object with isEmpty-method (public) isEmpty evaluates to true [FAIL] Not expected since object is not null. isEmpty evaluates to false [ OK ] Expected. non-null object with isEmpty-method (package-private) - isEmpty evaluates to true [ OK ] Expected. isEmpty evaluates to false [ OK ] Expected. {code} > Incorrect evaluation of IF-Directive for objects with isEmpty-method > > > Key: VELOCITY-911 > URL: https://issues.apache.org/jira/browse/VELOCITY-911 > Project: Velocity > Issue Type: Bug >Affects Versions: 2.0, 2.1 >Reporter: M. Luppi >Priority: Major > Attachments: VelocityIsEmptyBugMCVE.java, mcve-project.zip, > template.vm > > > With Velocity 2.0 the logic of evaluation for IF-Directives changed and now > uses an extended approach to determine whether it is true. This bug report > only refers to the case where $foo is an +object+. The documentation for 2.0 > and 2.1 state as follows: > {quote}The variable $foo is evaluated to determine whether it is true, which > will happen under one of those circumstances: [...] > $foo is an object (other than a string, a number or a collection) which is > not null > _Source: >
[jira] [Created] (VELOCITY-911) Incorrect evaluation of IF-Directive for objects with isEmpty-method
M. Luppi created VELOCITY-911: - Summary: Incorrect evaluation of IF-Directive for objects with isEmpty-method Key: VELOCITY-911 URL: https://issues.apache.org/jira/browse/VELOCITY-911 Project: Velocity Issue Type: Bug Affects Versions: 2.1, 2.0 Reporter: M. Luppi Attachments: VelocityIsEmptyBugMCVE.java, mcve-project.zip, template.vm With Velocity 2.0 the logic of evaluation for IF-Directives changed and now uses an extended approach to determine whether it is true. This bug report only refers to the case where $foo is an +object+. The documentation for 2.0 and 2.1 state as follows: {quote}The variable $foo is evaluated to determine whether it is true, which will happen under one of those circumstances: [...] $foo is an object (other than a string, a number or a collection) which is not null _Source: http://velocity.apache.org/engine/2.0/user-guide.html#if-elseif-else_ {quote} After a long debugging session I have found that objects with a public isEmpty-method are not being handled according to the documentation cited above. Thereby, such objects are evaluated as false if there is an isEmpty-method that returns false. The correct evaluation result according to the documentation should be true since the object is not null and not a string, a number or a collection. It gets even more confusing when we take access modifiers into account. If the access of the isEmpty-method is not public, the behaviour is as it should be. When we make it public, however, the above explained bug occurs in version 2.0 as well as 2.1. See the attached classes and the template or the whole project of the MCVE (minimal, complete, and verifiable example) as ZIP. The output of the test is as follows: {code:java} null object --- [ OK ] Expected. non-null object with isEmpty-method (public) isEmpty evaluates to true [FAIL] Not expected since object is not null. isEmpty evaluates to false [ OK ] Expected. non-null object with isEmpty-method (package-private) - isEmpty evaluates to true [ OK ] Expected. isEmpty evaluates to false [ OK ] Expected. {code} -- This message was sent by Atlassian JIRA (v7.6.3#76005) - To unsubscribe, e-mail: dev-unsubscr...@velocity.apache.org For additional commands, e-mail: dev-h...@velocity.apache.org