WP_Query::is_page() fails in certain cases when post titles include slashes.

[mikejolley]

In WP_Query::is_page(), the following evaluations are made to determine if the queried object matches the supplied page property:

`
if ( in_array( (string) $page_obj->ID, $page ) ) {

return true;

} elseif ( in_array( $page_obj->post_title, $page ) ) {

return true;

} elseif ( in_array( $page_obj->post_name, $page ) ) {

return true;

} else {
`

If you have a page with a slash in the name, for example, 4/6 Sample Page, WP_Query::is_page(4) returns true, even if the actual page ID is something else.

I traced this back to the line:

`
} elseif ( in_array( $page_obj->post_title, $page ) ) {
`

In my test case, $page is:

`
array(1) { [0]=> int(4) }
`

If you cast 4/6 Sample Page to int, it becomes int(4) causing the match. This comparison should be strict...

There was some discussion around this in ticket https://core.trac.wordpress.org/ticket/24674, however, I don't see a fix for the case I posted above. Only IDs were fixed.

When comparing string based post_titles, ideally the $page should be cast to string to prevent the above case returning true.

To fix this I believe we can do some more intelligent casting.

The first rule:

`
if ( in_array( (string) $page_obj->ID, $page ) ) {
`

ID is cast to string and compared against $page with type array, contents unknown.

The second rule we already know title is string:

`
} elseif ( in_array( $page_obj->post_title, $page ) ) {
`

Same for the postname rule:

`
} elseif ( in_array( $page_obj->post_name, $page ) ) {
`

Since all comparisons use string, we should be able to safely cast the array values to a string too:

`
$page = array_map( 'strval', (array) $page );
`

This fixes all comparisons and prevents the bug occurring.

I found this bug when investigating ​https://github.com/woothemes/woocommerce/issues/10404. Page name was 4/6 Sample Page, and in my case my shop page was ID #4. Because of this, checks for page ID #4 (shop) returned true on 4/6 Sample Page incorrectly.

Patch to follow...

[mikejolley]

Fix for 35901

[mikejolley]

I messed up my code snippets sorry about that. Cannot edit.

Patch here: https://core.trac.wordpress.org/attachment/ticket/35901/fix-35901.diff

[mikejolley]

Duplicate of #35902.