Slight tweak to no_found_rows logic in WP_Query

[dmchale]

It seems that edge cases could introduce times when a query WOULD have limits but NOT want them (when the query was passed nopaging=true or post_per_page=-1). When this happened, SQL_CALC_FOUND_ROWS would be invoked in the query and hinder performance of the query.

Code change still allows for a developer to override no_found_rows with their own value, but now checks the nopaging and post_per_page variables to possibly set no_found_rows to true anyway. By using one of those 2 variables to ask for EVERYTHING, we know the developer does not want/need pagination. This forces the issue so that by the time we get to the line...

if ( !$q['no_found_rows'] && !empty($limits) )

...we don't find ourselves WITH limits, and a False value for no_found_rows, in spite of the fact that the developer had asked for "all".

[boonebgorges]

Thanks for the patch, dmchale.

It seems that edge cases could introduce times when a query WOULD have limits but NOT want them (when the query was passed nopaging=true or post_per_page=-1)

I can't reproduce this. Check out the last two tests in 29552.tests.patch​. They declare nopaging=true and posts_per_page=-1, and in each case, you can see that the request query does *not* contain SQL_CALC_FOUND_ROWS. When you have LIMIT clauses, WP_Query does not append the SQL_CALC_FOUND_ROWS keyword. See https://core.trac.wordpress.org/browser/tags/4.0/src/wp-includes/query.php?annotate=blame#L3376. See also https://core.trac.wordpress.org/browser/tags/4.0/src/wp-includes/query.php?annotate=blame#L3611 to see how found_posts is set in these cases.

Can you say more about your "edge cases"?

[boonebgorges]

Assigning to myself to review the tests. If they are passing, I'll commit them and close the ticket as invalid, pending further details. If they're not passing, then maybe we have a bug on our hands.

[boonebgorges]

[37600] missed this ticket (fudged the commit message).

Tests seem OK to me, so I'm going to close as wontfix. If anyone has steps to reproduce, please feel free to reopen with details.