Last modified: 2013-07-03 13:48:39 UTC
There are issues when edit conflicts are occurring for claims: 1) User A edits a claim, User B edits the same claim without refreshing the page before, an error is shown saying "Exception Caught: Can only add \Wikibase\Claim implementing objects to Wikibase\Claims." but it should report an edit conflict instead. 2) User A edits a claim, User B edits the same claim but clicks on save without actually changing the claim. In that case the claim will be overwritten by User B without notice but an edit conflict should be detected instead.
When bailing on assert violations, you'll see the issue occurs before that point: Warning: assert(): Assertion failed in /home/j/www/phase3/extensions/Wikibase/lib/includes/claim/Claims.php on line 223 This means $claims->getByElementHash( $diffOp->getNewValue() ); is returning false (I have verified this) while the list should contain the claim. This makes me suspect there is a bug in HashArray, the class on which Claims is build. Not been able to track it down further so far.
Doing a dump of state causing the error: added under $claim = $claims->getByElementHash( $diffOp->getNewValue() ); if(!($claim instanceof Claim)) { q($this, $claims, $sourceHashes, $targetHashes, $claim); } <pre class='xdebug-var-dump' dir='ltr'> <b>object</b>(<i>Wikibase\Claims</i>)[<i>108</i>] <b>object</b>(<i>Wikibase\Statement</i>)[<i>66</i>] <i>protected</i> 'references' <font color='#888a85'>=></font> <b>object</b>(<i>Wikibase\ReferenceList</i>)[<i>109</i>] <i>protected</i> 'rank' <font color='#888a85'>=></font> <small>int</small> <font color='#4e9a06'>1</font> <i>protected</i> 'mainSnak' <font color='#888a85'>=></font> <b>object</b>(<i>Wikibase\PropertyValueSnak</i>)[<i>67</i>] <i>protected</i> 'dataValue' <font color='#888a85'>=></font> <b>object</b>(<i>Wikibase\EntityId</i>)[<i>68</i>] <i>protected</i> 'entityType' <font color='#888a85'>=></font> <small>string</small> <font color='#cc0000'>'item'</font> <i>(length=4)</i> <i>protected</i> 'numericId' <font color='#888a85'>=></font> <small>int</small> <font color='#4e9a06'>28</font> <i>protected</i> 'propertyId' <font color='#888a85'>=></font> <b>object</b>(<i>Wikibase\EntityId</i>)[<i>69</i>] <i>protected</i> 'entityType' <font color='#888a85'>=></font> <small>string</small> <font color='#cc0000'>'property'</font> <i>(length=8)</i> <i>protected</i> 'numericId' <font color='#888a85'>=></font> <small>int</small> <font color='#4e9a06'>14</font> <i>protected</i> 'qualifiers' <font color='#888a85'>=></font> <b>object</b>(<i>Wikibase\SnakList</i>)[<i>65</i>] <i>protected</i> 'guid' <font color='#888a85'>=></font> <small>string</small> <font color='#cc0000'>'q35$9191D62B-EC8A-45AD-8068-BEE0B60308E6'</font> <i>(length=40)</i> </pre> <pre class='xdebug-var-dump' dir='ltr'> <b>object</b>(<i>Wikibase\Claims</i>)[<i>110</i>] <b>object</b>(<i>Wikibase\Statement</i>)[<i>101</i>] <i>protected</i> 'references' <font color='#888a85'>=></font> <b>object</b>(<i>Wikibase\ReferenceList</i>)[<i>96</i>] <i>protected</i> 'rank' <font color='#888a85'>=></font> <small>int</small> <font color='#4e9a06'>1</font> <i>protected</i> 'mainSnak' <font color='#888a85'>=></font> <b>object</b>(<i>Wikibase\PropertyValueSnak</i>)[<i>88</i>] <i>protected</i> 'dataValue' <font color='#888a85'>=></font> <b>object</b>(<i>Wikibase\EntityId</i>)[<i>95</i>] <i>protected</i> 'entityType' <font color='#888a85'>=></font> <small>string</small> <font color='#cc0000'>'item'</font> <i>(length=4)</i> <i>protected</i> 'numericId' <font color='#888a85'>=></font> <small>int</small> <font color='#4e9a06'>22</font> <i>protected</i> 'propertyId' <font color='#888a85'>=></font> <b>object</b>(<i>Wikibase\EntityId</i>)[<i>104</i>] <i>protected</i> 'entityType' <font color='#888a85'>=></font> <small>string</small> <font color='#cc0000'>'property'</font> <i>(length=8)</i> <i>protected</i> 'numericId' <font color='#888a85'>=></font> <small>int</small> <font color='#4e9a06'>14</font> <i>protected</i> 'qualifiers' <font color='#888a85'>=></font> <b>object</b>(<i>Wikibase\SnakList</i>)[<i>94</i>] <i>protected</i> 'guid' <font color='#888a85'>=></font> <small>string</small> <font color='#cc0000'>'q35$9191D62B-EC8A-45AD-8068-BEE0B60308E6'</font> <i>(length=40)</i> </pre> <pre class='xdebug-var-dump' dir='ltr'> <b>array</b> <i>(size=1)</i> 0 <font color='#888a85'>=></font> <small>string</small> <font color='#cc0000'>'7efc8e1c8696d2a639dee79bb6d76ab190898aa3'</font> <i>(length=40)</i> </pre> <pre class='xdebug-var-dump' dir='ltr'> <b>array</b> <i>(size=1)</i> 0 <font color='#888a85'>=></font> <small>string</small> <font color='#cc0000'>'3cefed471aa6a8cb29eed34f006181d257d9ef6d'</font> <i>(length=40)</i> </pre> <pre class='xdebug-var-dump' dir='ltr'><small>boolean</small> <font color='#75507b'>false</font> </pre>
https://gerrit.wikimedia.org/r/#/c/46814/
(In reply to comment #3) > https://gerrit.wikimedia.org/r/#/c/46814/ Update Issue 1: After that change got merged the error message changed from "Exception Caught: Can only add \Wikibase\Claim implementing objects to Wikibase\Claims." to "Failed to save the change" but it should be "Edit not allowed: Edit conflict." in that case. Update Issue 2: This issue is still there.
related patchsets: https://gerrit.wikimedia.org/r/#/c/60870/ https://gerrit.wikimedia.org/r/#/c/60872/
Issue I is solved.
Issue II should be solved by merit of unchanged values not being possible to save.
