From 907b5fc52724e5ec28baeb25323187c683ecd0a0 Mon Sep 17 00:00:00 2001
From: "Dominik Schilling (ocean90)" <ocean90@git.wordpress.org>
Date: Thu, 29 Sep 2016 22:35:32 +0000
Subject: [PATCH] Taxonomy: Use `WP_Term_Query` in `get_term_by()`.

`WP_Term_Query` already supports querying terms by 'slug', 'name', and 'term_taxonomy_id'. Its additional arguments allow us to generate nearly the same SQL queries as before.
This change has one yuge benefit: the term queries are now cached.

Add tests to increase coverage of `get_term_by()`.

Props spacedmonkey, boonebgorges, johnjamesjacoby, pento, ocean90.
Fixes #21760.

git-svn-id: https://develop.svn.wordpress.org/trunk@38677 602fd350-edb4-49c9-b593-d223f7449a82
---
 src/wp-includes/taxonomy.php           |  54 ++++----
 tests/phpunit/tests/term/cache.php     | 171 +++++++++++++++++++++++++
 tests/phpunit/tests/term/getTermBy.php | 105 +++++++++++++++
 3 files changed, 306 insertions(+), 24 deletions(-)

diff --git a/src/wp-includes/taxonomy.php b/src/wp-includes/taxonomy.php
index 5767ebf7a3..a39fa47518 100644
--- a/src/wp-includes/taxonomy.php
+++ b/src/wp-includes/taxonomy.php
@@ -927,49 +927,55 @@ function get_term( $term, $taxonomy = '', $output = OBJECT, $filter = 'raw' ) {
  *                      or `$term` was not found.
  */
 function get_term_by( $field, $value, $taxonomy = '', $output = OBJECT, $filter = 'raw' ) {
-	global $wpdb;
 
 	// 'term_taxonomy_id' lookups don't require taxonomy checks.
 	if ( 'term_taxonomy_id' !== $field && ! taxonomy_exists( $taxonomy ) ) {
 		return false;
 	}
 
-	$tax_clause = $wpdb->prepare( "AND tt.taxonomy = %s", $taxonomy );
-
-	if ( 'slug' == $field ) {
-		$_field = 't.slug';
-		$value = sanitize_title($value);
-		if ( empty($value) )
-			return false;
-	} elseif ( 'name' == $field ) {
-		// Assume already escaped
-		$value = wp_unslash($value);
-		$_field = 't.name';
-	} elseif ( 'term_taxonomy_id' == $field ) {
-		$value = (int) $value;
-		$_field = 'tt.term_taxonomy_id';
-
-		// No `taxonomy` clause when searching by 'term_taxonomy_id'.
-		$tax_clause = '';
-	} else {
+	if ( 'id' === $field || 'term_id' === $field ) {
 		$term = get_term( (int) $value, $taxonomy, $output, $filter );
-		if ( is_wp_error( $term ) || is_null( $term ) ) {
+		if ( is_wp_error( $term ) || null === $term ) {
 			$term = false;
 		}
 		return $term;
 	}
 
-	$term = $wpdb->get_row( $wpdb->prepare( "SELECT t.*, tt.* FROM $wpdb->terms AS t INNER JOIN $wpdb->term_taxonomy AS tt ON t.term_id = tt.term_id WHERE $_field = %s", $value ) . " $tax_clause LIMIT 1" );
-	if ( ! $term )
+	$args = array(
+		'get'                    => 'all',
+		'number'                 => 1,
+		'taxonomy'               => $taxonomy,
+		'update_term_meta_cache' => false,
+		'orderby'                => 'none',
+	);
+
+	switch ( $field ) {
+		case 'slug' :
+			$args['slug'] = $value;
+			break;
+		case 'name' :
+			$args['name'] = $value;
+			break;
+		case 'term_taxonomy_id' :
+			$args['term_taxonomy_id'] = $value;
+			unset( $args[ 'taxonomy' ] );
+			break;
+		default :
+			return false;
+	}
+
+	$terms = get_terms( $args );
+	if ( is_wp_error( $terms ) || empty( $terms ) ) {
 		return false;
+	}
+
+	$term = array_shift( $terms );
 
 	// In the case of 'term_taxonomy_id', override the provided `$taxonomy` with whatever we find in the db.
 	if ( 'term_taxonomy_id' === $field ) {
 		$taxonomy = $term->taxonomy;
 	}
 
-	wp_cache_add( $term->term_id, $term, 'terms' );
-
 	return get_term( $term, $taxonomy, $output, $filter );
 }
 
diff --git a/tests/phpunit/tests/term/cache.php b/tests/phpunit/tests/term/cache.php
index 8d9f51ada2..1ce755bf3a 100644
--- a/tests/phpunit/tests/term/cache.php
+++ b/tests/phpunit/tests/term/cache.php
@@ -219,4 +219,175 @@ class Tests_Term_Cache extends WP_UnitTestCase {
 			$this->assertSame( $p, $term->object_id );
 		}
 	}
+
+	/**
+	 * @ticket 21760
+	 */
+	function test_get_term_by_slug_cache() {
+		global $wpdb;
+
+		$term_id = $this->factory->term->create( array( 'slug' => 'burrito', 'name' => 'Taco', 'taxonomy' => 'post_tag' ) );
+
+		clean_term_cache( $term_id, 'post_tag' );
+		$num_queries = $wpdb->num_queries;
+
+		$term = get_term_by( 'slug', 'burrito', 'post_tag' );
+		$num_queries++;
+		$this->assertEquals( 'Taco', $term->name );
+		$this->assertEquals( $num_queries, $wpdb->num_queries );
+
+		// This should now hit cache.
+		$term = get_term_by( 'slug', 'burrito', 'post_tag' );
+		$this->assertEquals( 'Taco', $term->name );
+		$this->assertEquals( $num_queries, $wpdb->num_queries );
+
+		$this->assertEquals( get_term( $term_id, 'post_tag' ), $term );
+		$this->assertEquals( $num_queries, $wpdb->num_queries );
+	}
+
+	/**
+	 * @ticket 21760
+	 */
+	function test_get_term_by_slug_cache_update() {
+		global $wpdb;
+
+		$term_id = $this->factory->term->create( array( 'slug' => 'burrito', 'name' => 'Taco', 'taxonomy' => 'post_tag' ) );
+
+		clean_term_cache( $term_id, 'post_tag' );
+		$num_queries = $wpdb->num_queries;
+
+		$term = get_term_by( 'slug', 'burrito', 'post_tag' );
+		$num_queries++;
+		$this->assertEquals( 'Taco', $term->name );
+		$this->assertEquals( $num_queries, $wpdb->num_queries );
+
+		// This should now hit cache.
+		$term = get_term_by( 'slug', 'burrito', 'post_tag' );
+		$this->assertEquals( 'Taco', $term->name );
+		$this->assertEquals( $num_queries, $wpdb->num_queries );
+
+		// Update the tag which invalidates the cache.
+		wp_update_term( $term_id, 'post_tag', array( 'name' => 'No Taco' ) );
+		$num_queries = $wpdb->num_queries;
+
+		// This should not hit cache.
+		$term = get_term_by( 'slug', 'burrito', 'post_tag' );
+		$num_queries++;
+		$this->assertEquals( 'No Taco', $term->name );
+		$this->assertEquals( $num_queries, $wpdb->num_queries );
+	}
+
+	/**
+	 * @ticket 21760
+	 */
+	function test_get_term_by_name_cache() {
+		global $wpdb;
+
+		$term_id = $this->factory->term->create( array( 'name' => 'Burrito', 'slug' => 'noburrito', 'taxonomy' => 'post_tag' ) );
+
+		clean_term_cache( $term_id, 'post_tag' );
+		$num_queries = $wpdb->num_queries;
+
+		get_term_by( 'name', 'Burrito', 'post_tag' );
+		$num_queries++;
+		$this->assertEquals( $num_queries, $wpdb->num_queries );
+
+		// This should now hit cache.
+		$term = get_term_by( 'name', 'Burrito', 'post_tag' );
+		$this->assertEquals( $num_queries, $wpdb->num_queries );
+
+		$this->assertEquals( get_term( $term_id, 'post_tag' ), $term );
+		$this->assertEquals( $num_queries, $wpdb->num_queries );
+	}
+
+	/**
+	 * @ticket 21760
+	 */
+	function test_get_term_by_name_cache_update() {
+		global $wpdb;
+
+		$term_id = $this->factory->term->create( array( 'name' => 'Burrito', 'slug' => 'noburrito', 'taxonomy' => 'post_tag' ) );
+
+		clean_term_cache( $term_id, 'post_tag' );
+		$num_queries = $wpdb->num_queries;
+
+		get_term_by( 'name', 'Burrito', 'post_tag' );
+		$num_queries++;
+		$this->assertEquals( $num_queries, $wpdb->num_queries );
+
+		// This should now hit cache.
+		get_term_by( 'name', 'Burrito', 'post_tag' );
+		$this->assertEquals( $num_queries, $wpdb->num_queries );
+
+		// Update the tag which invalidates the cache.
+		wp_update_term( $term_id, 'post_tag', array( 'slug' => 'taco' ) );
+		$num_queries = $wpdb->num_queries;
+
+		// This should not hit cache.
+		get_term_by( 'name', 'burrito', 'post_tag' );
+		$num_queries++;
+		$this->assertEquals( $num_queries, $wpdb->num_queries );
+	}
+
+	/**
+	 * @ticket 21760
+	 */
+	function test_invalidating_term_caches_should_fail_when_invalidation_is_suspended() {
+		global $wpdb;
+
+		$term_id = $this->factory->term->create( array( 'name' => 'Burrito', 'taxonomy' => 'post_tag' ) );
+
+		clean_term_cache( $term_id, 'post_tag' );
+		$num_queries = $wpdb->num_queries;
+		$last_changed = wp_cache_get( 'last_changed', 'terms' );
+
+		$term1 = get_term_by( 'name', 'Burrito', 'post_tag' );
+		$num_queries++;
+
+		// Verify the term is cached.
+		$term2 = get_term_by( 'name', 'Burrito', 'post_tag' );
+		$this->assertEquals( $num_queries, $wpdb->num_queries );
+		$this->assertEquals( $term1, $term2 );
+
+		$suspend = wp_suspend_cache_invalidation();
+
+		// Update the tag.
+		wp_update_term( $term_id, 'post_tag', array( 'name' => 'Taco' ) );
+		$num_queries = $wpdb->num_queries;
+
+		// Verify that the cached term still matches the initial cached term.
+		$term3 = get_term_by( 'name', 'Burrito', 'post_tag' );
+		$this->assertEquals( $num_queries, $wpdb->num_queries );
+		$this->assertEquals( $term1, $term3 );
+
+		// Verify that last changed has not been updated as part of an invalidation routine.
+		$this->assertSame( $last_changed, wp_cache_get( 'last_changed', 'terms' ) );
+
+		// Clean up.
+		wp_suspend_cache_invalidation( $suspend );
+	}
+
+	/**
+	 * @ticket 21760
+	 */
+	public function test_get_term_by_does_not_prime_term_meta_cache() {
+		global $wpdb;
+
+		$term_id = $this->factory->term->create( array( 'name' => 'Burrito', 'taxonomy' => 'post_tag' ) );
+		add_term_meta( $term_id, 'foo', 'bar' );
+
+		clean_term_cache( $term_id, 'post_tag' );
+		$num_queries = $wpdb->num_queries;
+
+		$term = get_term_by( 'name', 'Burrito', 'post_tag' );
+		$num_queries++;
+		$this->assertTrue( $term instanceof WP_Term );
+		$this->assertSame( $term_id, $term->term_id );
+		$this->assertEquals( $num_queries, $wpdb->num_queries );
+
+		$term_meta = get_term_meta( $term_id, 'foo', true );
+		$num_queries++;
+		$this->assertSame( $term_meta, 'bar' );
+		$this->assertEquals( $num_queries, $wpdb->num_queries );
+	}
 }
diff --git a/tests/phpunit/tests/term/getTermBy.php b/tests/phpunit/tests/term/getTermBy.php
index 9d80ab643e..bd71d3fc49 100644
--- a/tests/phpunit/tests/term/getTermBy.php
+++ b/tests/phpunit/tests/term/getTermBy.php
@@ -4,6 +4,34 @@
  * @group taxonomy
  */
 class Tests_Term_GetTermBy extends WP_UnitTestCase {
+
+	function test_get_term_by_slug() {
+		$term1 = wp_insert_term( 'Foo', 'category', array( 'slug' => 'foo' ) );
+		$term2 = get_term_by( 'slug', 'foo', 'category' );
+		$this->assertEquals( get_term( $term1['term_id'], 'category' ), $term2 );
+	}
+
+	function test_get_term_by_name() {
+		$term1 = wp_insert_term( 'Foo', 'category', array( 'slug' => 'foo' ) );
+		$term2 = get_term_by( 'name', 'Foo', 'category' );
+		$this->assertEquals( get_term( $term1['term_id'], 'category' ), $term2 );
+	}
+
+	function test_get_term_by_id() {
+		$term1 = wp_insert_term( 'Foo', 'category', array( 'slug' => 'foo' ) );
+		$term2 = get_term_by( 'id', $term1['term_id'], 'category' );
+		$this->assertEquals( get_term( $term1['term_id'], 'category' ), $term2 );
+	}
+
+	/**
+	 * 'term_id' is an alias of 'id'.
+	 */
+	function test_get_term_by_term_id() {
+		$term1 = wp_insert_term( 'Foo', 'category', array( 'slug' => 'foo' ) );
+		$term2 = get_term_by( 'term_id', $term1['term_id'], 'category' );
+		$this->assertEquals( get_term( $term1['term_id'], 'category' ), $term2 );
+	}
+
 	/**
 	 * @ticket 21651
 	 */
@@ -13,6 +41,12 @@ class Tests_Term_GetTermBy extends WP_UnitTestCase {
 		$this->assertEquals( get_term( $term1['term_id'], 'category' ), $term2 );
 	}
 
+	function test_get_term_by_unknown() {
+		wp_insert_term( 'Foo', 'category', array( 'slug' => 'foo' ) );
+		$term2 = get_term_by( 'unknown', 'foo', 'category' );
+		$this->assertFalse( $term2 );
+	}
+
 	/**
 	 * @ticket 33281
 	 */
@@ -87,4 +121,75 @@ class Tests_Term_GetTermBy extends WP_UnitTestCase {
 		$this->assertSame( $t, $found->term_id );
 		$this->assertSame( $num_queries, $wpdb->num_queries );
 	}
+
+	/**
+	 * @ticket 21760
+	 */
+	public function test_should_unslash_name() {
+		register_taxonomy( 'wptests_tax', 'post' );
+		$term_name = 'Foo " \o/';
+		$term_name_slashed = wp_slash( $term_name );
+		$t = self::factory()->term->create( array(
+			'taxonomy' => 'wptests_tax',
+			'name' => $term_name_slashed,
+		) );
+
+		$found = get_term_by( 'name', $term_name_slashed, 'wptests_tax' );
+
+		$this->assertTrue( $found instanceof WP_Term );
+		$this->assertSame( $t, $found->term_id );
+		$this->assertSame( $term_name, $found->name );
+	}
+
+	/**
+	 * @ticket 21760
+	 */
+	public function test_should_sanitize_slug() {
+		register_taxonomy( 'wptests_tax', 'post' );
+		$t1 = self::factory()->term->create( array(
+			'taxonomy' => 'wptests_tax',
+			'slug' => 'foo-foo',
+		) );
+
+		// Whitespace should get replaced by a '-'.
+		$found1 = get_term_by( 'slug', 'foo foo', 'wptests_tax' );
+
+		$this->assertTrue( $found1 instanceof WP_Term );
+		$this->assertSame( $t1, $found1->term_id );
+
+		$t2 = self::factory()->term->create( array(
+			'taxonomy' => 'wptests_tax',
+			'slug' => '%e4%bb%aa%e8%a1%a8%e7%9b%98',
+		) );
+
+		// Slug should get urlencoded.
+		$found2 = get_term_by( 'slug', '仪表盘', 'wptests_tax' );
+
+		$this->assertTrue( $found2 instanceof WP_Term );
+		$this->assertSame( $t2, $found2->term_id );
+	}
+
+	/**
+	 * @ticket 21760
+	 */
+	public function test_query_should_not_contain_order_by_clause() {
+		global $wpdb;
+
+		$term_id = $this->factory->term->create( array( 'name' => 'burrito', 'taxonomy' => 'post_tag' ) );
+		$found = get_term_by( 'name', 'burrito', 'post_tag' );
+		$this->assertSame( $term_id, $found->term_id );
+		$this->assertNotContains( 'ORDER BY', $wpdb->last_query );
+	}
+
+	/**
+	 * @ticket 21760
+	 */
+	public function test_query_should_contain_limit_clause() {
+		global $wpdb;
+
+		$term_id = $this->factory->term->create( array( 'name' => 'burrito', 'taxonomy' => 'post_tag' ) );
+		$found = get_term_by( 'name', 'burrito', 'post_tag' );
+		$this->assertSame( $term_id, $found->term_id );
+		$this->assertContains( 'LIMIT 1', $wpdb->last_query );
+	}
 }