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Opened 3 years ago

Last modified 4 days ago

#21790 assigned defect (bug)

When set a static front page WP main query isn't set correctly

Reported by: markoheijnen Owned by: SergeyBiryukov
Milestone: 4.3 Priority: normal
Severity: normal Version: 3.4.1
Component: Query Keywords: needs-patch
Focuses: Cc:


In my project I use on several places pre_get_posts filter. When setting a static frontpage and blog page I get several notices on my screen. When I var_dump the main query the only value that is set it the page_id.
Even the post_type isn't set.

Attachments (1)

21790.diff (1.7 KB) - added by collinsinternet 8 weeks ago.
Unit test that catches PHP notice on pre_get_post when static front page is set.

Download all attachments as: .zip

Change History (25)

comment:1 follow-up: @nacin3 years ago

The notices are?

comment:2 in reply to: ↑ 1 @markoheijnen3 years ago

Replying to nacin:

The notices are?

Notice: Undefined property: WP_Query::$post in /var/www/vhosts/*/subdomains/*/httpdocs/wp-includes/query.php on line 2986

Notice: Trying to get property of non-object in /var/www/vhosts/*/subdomains/*/httpdocs/wp-includes/post-template.php on line 1270

Notice: Undefined property: WP_Query::$post in /var/www/vhosts/*/subdomains/*/httpdocs/wp-includes/query.php on line 2986

Notice: Trying to get property of non-object in /var/www/vhosts/*/subdomains/*/httpdocs/wp-includes/query.php on line 3349

Notice: Trying to get property of non-object in /var/www/vhosts/*/subdomains/*/httpdocs/wp-includes/query.php on line 3351

Notice: Trying to get property of non-object in /var/www/vhosts/*/subdomains/*/httpdocs/wp-includes/query.php on line 3353

comment:3 follow-up: @markoheijnen3 years ago

In my case I'm using is_page_template() and is_front_page() on the filter. How I look in the code this will only work inside the loop but I can be wrong. However I somehow do expect it to work without the need of a loop.

comment:4 @nacin3 years ago

Could you include a simple test case that can reproduce this?

comment:5 @markoheijnen3 years ago

For me to see the notices is to set a static blog and front page. and use a function like is_front_page. I'm going to try if I can write an unit-test to make it visible. Not sure yet how to create this situation and where to check on.

function some_random_modification( $query ) {
		if( $query->is_main_query() && is_front_page() ) {

		return $query;
add_filter( 'pre_get_posts', 'some_random_modification' );

comment:6 in reply to: ↑ 3 @SergeyBiryukov3 years ago

is_front_page() calls is_page(), which only works on 'wp' action or later.

'pre_get_posts' is too early to use conditional tags (this is also mentioned on the Codex page).

comment:7 @markoheijnen3 years ago

Uhm okay, i do think it is wrong tho. 'pre_get_posts' is a place you want to use it since you want to control the main query.

How I can see it now there is no way to do it then. Having said that it does work. I only get some notices.

comment:8 @markoheijnen3 years ago

Just a little note what I already said: it only shows the notices when static homepage is set. On all other pages it is fine without any notice.

comment:9 @SergeyBiryukov3 years ago

Well, is_front_page() only calls is_page() when a static home page is set:

The notices are coming from get_queried_object(), where $this->post is not filled yet:

So $page_obj in is_page() ends up being null:

Last edited 3 years ago by SergeyBiryukov (previous) (diff)

comment:10 @markoheijnen3 years ago

yes, I know that. I looked through the code to see if I could fix it.

I'm now just curious if it is fixable or how you otherwise modify the query on the front page with the use of WordPress code.

comment:11 @markoheijnen3 years ago

I now solved the issue by using this:

( $query->get('page_id') == get_option('page_on_front') || is_front_page() )

Reason was that is_front_page() doesn't work then in pre_get_posts(). It does work but I'm not a fan of using this.

comment:12 @wonderboymusic2 years ago

  • Keywords dev-feedback removed
  • Milestone Awaiting Review deleted
  • Resolution set to wontfix
  • Status changed from new to closed

This ticket appears to be dead - reopen if you think this needs a fix, Marko

comment:13 @markoheijnen2 years ago

Ticket is dead since I have no clue how to fix it. The problem is that even core developers say you can use is_front_page() or is_home on the hook pre_get_posts but you can't since it needs the page obj if a static page has been set. It also will fail then.

So no clue if the code should be fixed or the story we tell to developers.

comment:14 @markoheijnen21 months ago

  • Resolution wontfix deleted
  • Status changed from closed to reopened

Reopening the ticket. This needs a code fix or documentation fix.

comment:15 @SergeyBiryukov21 months ago

  • Milestone set to Awaiting Review

comment:16 @wonderboymusic15 months ago

  • Keywords needs-patch needs-unit-tests added
  • Milestone changed from Awaiting Review to 4.0

This seems tangentially related to #27015 - will review both

comment:17 @helen12 months ago

  • Milestone changed from 4.0 to Awaiting Review

#27015 isn't happening in 4.0.

comment:18 @ircbot12 months ago

This ticket was mentioned in IRC in #wordpress-dev by SergeyBiryukov. View the logs.

comment:19 @SergeyBiryukov11 months ago

#28728 was marked as a duplicate.

comment:20 @SergeyBiryukov7 months ago

  • Keywords 4.2-early added
  • Milestone changed from Awaiting Review to Future Release

Just got bitten by this, trying to use is_front_page() in pre_get_posts.

Looks like the patch on #27015 should resolve this.

comment:21 @obenland2 months ago

  • Owner set to SergeyBiryukov
  • Status changed from reopened to assigned

comment:22 @obenland2 months ago

  • Keywords 4.2-early removed
  • Milestone changed from Future Release to 4.3

@collinsinternet8 weeks ago

Unit test that catches PHP notice on pre_get_post when static front page is set.

comment:23 @collinsinternet8 weeks ago

  • Keywords needs-unit-tests removed

comment:24 @slackbot4 days ago

This ticket was mentioned in Slack in #core by jorbin. View the logs.

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