_wp_put_post_revision checks for errors incorrectly

[rmccue]

_wp_put_post_revision uses wp_insert_post, then checks is_wp_error to pass it up the stack (lines 259-261). However, wp_insert_post only returns a WP_Error if the second param is true. In this case, it is not.

Introduced in r7907.

[rmccue]

Specify we want a WP_Error on insertion error

[rmccue]

Correct some coding standards while we're in here

[rmccue]

Attached patches specify that we want a WP_Error back from wp_insert_post, pretty straight forward patch.

30009.diff​ fixes the problem, 30009.2.diff​ goes a bit further and corrects coding standards in the function while we're in there.

[adamsilverstein]

update docblock

[adamsilverstein]

looks good. I updated the doc block slightly in 30009.3.diff​ to reflect the return value.

I tried to write a unit test for this and couldn't actually get wp_insert_post to return an error - it only does so when get_post( post_id ) fails (returns null) and that check already happens earlier in _wp_put_post_revision. For this reason, I believe we could remove the entire error check conditional, we are returning $revision_id in any case...

Good catch in any case, the check as is will never work!

Replying to rmccue:

Attached patches specify that we want a WP_Error back from wp_insert_post, pretty straight forward patch.

30009.diff​ fixes the problem, 30009.2.diff​ goes a bit further and corrects coding standards in the function while we're in there.

[adamsilverstein]

30009.4.diff​

• Refresh against trunk

Lets keep this patch simple and stick to adding the true value to wp_insert_post so it will potentially return the WP_Error we are looking out for.

[adamsilverstein]

Fine leaving closed, this was fixed in WordPress 5.0: ​https://github.com/WordPress/wordpress-develop/blob/c2390f96a212aa57afe076bfe098c5b1676f5ec6/src/wp-includes/rest-api/endpoints/class-wp-rest-autosaves-controller.php#L365