wp_get_object_terms() returns duplicate terms if more than one taxonomy is given in args

[mranner]

works correct

$list = wp_get_object_terms([ 104627 ], [ 'produkte' ]);
print_r($list);

returns all terms for produkte and herkunft and merges all terms related to the post

$list = wp_get_object_terms([ 104627 ], [ 'produkte', 'herkunft' ]);
print_r($list);

Problem is unset( $taxonomies[ $index ] ) followed by $terms = array_merge( $terms, get_terms( $args ) );

foreach ( $taxonomies as $index => $taxonomy ) {} iterates for all given taxonomies and leaves an empty $taxonomies array. get_terms() with an empty array for $argstaxonomy? returns "all" related terms and merges with the terms of the previews loop run.

Michael

[Howdy_McGee]

I'm not sure I follow the latter half of your issue. I've tested wp_get_object_terms() with Post array( 'category', 'post_tag' ); and I get the expected results, no duplicates. Can you list steps to reproduce this issue?

[bor0]

Please use the following code to reproduce: ​https://gist.github.com/bor0/109e091c4aa625cbe670766db53ae5e1.

[peterwilsoncc]

@bor0,

Thanks for including the gist with some test data. In the WordPress Develop repository (​git | ​svn) there is a tests folder for phpunit.

Are you able to take a look at converting your gist to unit tests.

Pete

[bor0]

@peterwilsoncc sounds good to me.

I'll try to supply a UT sometime today or tomorrow.

In the meanwhile, can you assign a milestone for this so that it doesn't get lost?

Thanks!

[peterwilsoncc]

@bor0 I've put this against 4.9

[atanasangelovdev]

Added a unit test

[atanasangelovdev]

I've added a unit test to the patch with comments about what triggers the error (the unsupported "args" key).
Not sure about the test name - it probably needs a better one.

[boonebgorges]

@bor0 and @atanasangelovdev - Thanks for the patch and especially for the unit test, which helped me to understand the issue better.

This is a regression caused by [40514] in 4.7.5. For this reason, I think it's appropriate to fix in 4.8.1. In order to include in a minor release, I'd appreciate a review by another committer. @peterwilsoncc Since you've commented here, would you mind verifying the issue and the fix offered in 41010.3.patch​ (which does some slight modification to the code style in the unit test to better align with WP standards)?

[peterwilsoncc]

@boonebgorges,

I've checked this out, verified the issue exists and the fix works.

[boonebgorges]

In 41037:

Taxonomy: Avoid duplicates when querying for terms in taxonomies registered with $args parameter.

[40514] introduced a bug that caused term queries to return some duplicates
when the $taxonomies array contained only taxonomies that were originally
registered with an $args array. We fix this bug by ensuring that
recursive get_terms() queries stop when all queried $taxonomies have
already been referenced.

Props bor0, atanasangelovdev.
Fixes #41010.

[boonebgorges]

In 41038:

Taxonomy: Avoid duplicates when querying for terms in taxonomies registered with $args parameter.

[40514] introduced a bug that caused term queries to return some duplicates
when the $taxonomies array contained only taxonomies that were originally
registered with an $args array. We fix this bug by ensuring that
recursive get_terms() queries stop when all queried $taxonomies have
already been referenced.

Ports [41037] to the 4.8 branch.

Props bor0, atanasangelovdev.
Fixes #41010.