Changeset 41377

Timestamp:

09/13/2017 02:47:07 PM (7 years ago)

Author:

boonebgorges

Message:

Taxonomy: Force a DISTINCT term query when result count matters.

Generally, duplicate terms returned by a term query are eliminated in PHP,
after the database query takes place. This technique doesn't work properly
when the query parameters specify the number of results, since the results
of a SELECT ... LIMIT x... query may be deduplicated to a count less than
x. In these cases, we force the original query to be DISTINCT.

Props elvishp2006.
Fixes #41796.

Location:

trunk

Files:

• src/wp-includes/class-wp-term-query.php (modified) (3 diffs)
• tests/phpunit/tests/term/query.php (modified) (1 diff)

trunk/src/wp-includes/class-wp-term-query.php

@@ -552 +552 @@
         }
 
+        $do_distinct = false;
+
+        /*
+         * Duplicate terms are generally removed when necessary after the database query.
+         * But when a LIMIT clause is included in the query, we let MySQL enforce
+         * distinctness so the count is correct.
+         */
+        if ( ! empty( $limits ) && 'all_with_object_id' !== $args['fields'] ) {
+            $do_distinct = true;
+        }
 
         if ( ! empty( $args['search'] ) ) {
@@ -569 +579 @@
             $join .= $mq_sql['join'];
             $this->sql_clauses['where']['meta_query'] = preg_replace( '/^\s*AND\s*/', '', $mq_sql['where'] );
-            $distinct .= "DISTINCT";
-
+            $do_distinct = true;
         }
 
@@ -632 +641 @@
         $where = implode( ' AND ', $this->sql_clauses['where'] );
 
+        $distinct = $do_distinct ? 'DISTINCT' : '';
+
         /**
          * Filters the terms query SQL clauses.

trunk/tests/phpunit/tests/term/query.php

@@ -428 +428 @@
         $this->assertEquals( array( $term_ids[1], $term_ids[0], 1 ), wp_list_pluck( $terms, 'term_id' ) );
     }
+
+    /**
+     * @ticket 41796
+     */
+    public function test_number_should_work_with_object_ids() {
+        register_taxonomy( 'wptests_tax', 'post' );
+
+        $term_1 = self::factory()->term->create( array(
+            'taxonomy' => 'wptests_tax',
+        ) );
+        $term_2 = self::factory()->term->create( array(
+            'taxonomy' => 'wptests_tax',
+        ) );
+
+        $post_1 = self::factory()->post->create();
+        $post_2 = self::factory()->post->create();
+
+        wp_set_object_terms( $post_1, array( $term_1, $term_2 ), 'wptests_tax' );
+        wp_set_object_terms( $post_2, array( $term_1 ), 'wptests_tax' );
+
+        $q = new WP_Term_Query( array(
+            'taxonomy' => 'wptests_tax',
+            'object_ids' => array( $post_1, $post_2 ),
+            'number' => 2,
+        ) );
+
+        $this->assertEqualSets( array( $term_1, $term_2 ), wp_list_pluck( $q->terms, 'term_id' ) );
+    }
+
+    /**
+     * @ticket 41796
+     */
+    public function test_number_should_work_with_object_ids_and_all_with_object_id() {
+        register_taxonomy( 'wptests_tax', 'post' );
+
+        $term_1 = self::factory()->term->create( array(
+            'taxonomy' => 'wptests_tax',
+        ) );
+        $term_2 = self::factory()->term->create( array(
+            'taxonomy' => 'wptests_tax',
+        ) );
+
+        $post_1 = self::factory()->post->create();
+        $post_2 = self::factory()->post->create();
+
+        wp_set_object_terms( $post_1, array( $term_1, $term_2 ), 'wptests_tax' );
+        wp_set_object_terms( $post_2, array( $term_1 ), 'wptests_tax' );
+
+        $q = new WP_Term_Query( array(
+            'taxonomy' => 'wptests_tax',
+            'object_ids' => array( $post_1, $post_2 ),
+            'fields' => 'all_with_object_id',
+            'number' => 2,
+        ) );
+
+        $this->assertEqualSets( array( $term_1, $term_1 ), wp_list_pluck( $q->terms, 'term_id' ) );
+    }
 }