[jira] [Comment Edited] (GROOVY-8200) Shorthand |= results in NPE

["Daniel Hammer (JIRA)" <ji...@apache.org>]

    [ https://issues.apache.org/jira/browse/GROOVY-8200?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16022473#comment-16022473 ] 

Daniel Hammer edited comment on GROOVY-8200 at 5/24/17 7:56 AM:
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@[~blackdrag], I'm sorry but it seems my explanation wasn't clear enough. 

{quote}... Similar for the logic and binary and.{quote}

By executing the attached examples you'll be able to confirm that {{x |= null}} throws NPE and {{x &= null}} adheres to Groovy truth.
That's an inconsistency regarding null-handling in the |= shorthand notation and violates the [principle of least astonishment|https://en.wikipedia.org/wiki/Principle_of_least_astonishment].


was (Author: dleh):
@[~blackdrag], I'm sorry but it seems my explanation wasn't clear enough. 

{quote}... Similar for the logic and binary and.{quote}

By executing the attached examples you'l be able to confirm that {{x |= null}} throws NPE and {{x &= null}} adheres to Groovy truth.
That's an inconsistency regarding null-handling in the |= shorthand notation and violates the [principle of least astonishment|https://en.wikipedia.org/wiki/Principle_of_least_astonishment].

> Shorthand |= results in NPE
> ---------------------------
>
>                 Key: GROOVY-8200
>                 URL: https://issues.apache.org/jira/browse/GROOVY-8200
>             Project: Groovy
>          Issue Type: Bug
>    Affects Versions: 2.3.11
>         Environment: Groovy Version: 2.3.11 JVM: 1.7.0_80 Vendor: Oracle Corporation OS: Linux
> java version "1.7.0_80"
> Java(TM) SE Runtime Environment (build 1.7.0_80-b15)
> Java HotSpot(TM) 64-Bit Server VM (build 24.80-b11, mixed mode)
>            Reporter: Daniel Hammer
>            Assignee: Jochen Theodorou
>         Attachments: shorthand_and.groovy, shorthand_or_symptom.groovy
>
>
> I've stumbled across some curious behaviour for the shorthand assignment operator in Groovy v2.3.11 (symptom also present in Groovy v2.4.9).
> The following [boolean or logic|^shorthand_or_symptom.groovy], unexpectedly throws {{NullPointerException}}.
> {code}boolean x = null
> // short hand unrolled:  x = null || x
> x |= null // -> unexpected NullPointerException
> assert !x{code}
> The same approach for [boolean and logic|^shorthand_and.groovy], performs as expected.
> {code}boolean x = null
> // short hand unrolled:  x = null && x
> x &= null
> assert !x{code}
> It's possible to work around the issue with explicit cast.
> {code}x |= null as boolean{code}



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