Permalinks: Sanitize non-visible characters inside `sanitize_title_with_dashes()`.

This change prevents non-visible characters in titles from creating encoded values in permalinks, opting instead for the following replacement strategy:

* Non-visible non-zero-width characters are replaced with hyphens
* Non-visible zero-width characters are removed entirely

Included with this change are 64 additional PHPUnit assertions to confirm that only the targeted non-visible characters are sanitized as intended.

Before this change, URLs would unintentionally contain encoded values where these non-visible characters were. After this change, URLs intentionally strip out or hyphenate these non-visible characters.

Props costdev, dhanendran, hellofromtonya, paaljoachim, peterwilsoncc, poena, sergeybiryukov.

Fixes #47912.

git-svn-id: https://develop.svn.wordpress.org/trunk@51984 602fd350-edb4-49c9-b593-d223f7449a82

1 files changed, 210 insertions, 0 deletions

diff --git a/tests/phpunit/tests/formatting/sanitizeTitleWithDashes.php b/tests/phpunit/tests/formatting/sanitizeTitleWithDashes.php
index 024125f387..80438d4a94 100644
--- a/tests/phpunit/tests/formatting/sanitizeTitleWithDashes.php
+++ b/tests/phpunit/tests/formatting/sanitizeTitleWithDashes.php
@@ -147,4 +147,214 @@ class Tests_Formatting_SanitizeTitleWithDashes extends WP_UnitTestCase {
 		$this->assertSame( 'aaaa', sanitize_title_with_dashes( 'ááa´aˊ', '', 'save' ) );
 	}
 
+	/**
+	 * @ticket 47912
+	 * @dataProvider data_removes_non_visible_characters_without_width
+	 *
+	 * @param string $title     The title to be sanitized.
+	 * @param string $expected  Expected sanitized title.
+	 */
+	public function test_removes_non_visible_characters_without_width( $title, $expected = '' ) {
+		$this->assertSame( $expected, sanitize_title_with_dashes( $title, '', 'save' ) );
+	}
+
+	/**
+	 * Data provider.
+	 *
+	 * @return array
+	 */
+	public function data_removes_non_visible_characters_without_width() {
+		return array(
+			// Only the non-visible characters.
+			'only %e2%80%8b'     => array( '%e2%80%8b' ),
+			'only %e2%80%8c'     => array( '%e2%80%8c' ),
+			'only %e2%80%8d'     => array( '%e2%80%8d' ),
+			'only %e2%80%8e'     => array( '%e2%80%8e' ),
+			'only %e2%80%8f'     => array( '%e2%80%8f' ),
+			'only %e2%80%aa'     => array( '%e2%80%aa' ),
+			'only %e2%80%ab'     => array( '%e2%80%ab' ),
+			'only %e2%80%ac'     => array( '%e2%80%ac' ),
+			'only %e2%80%ad'     => array( '%e2%80%ad' ),
+			'only %e2%80%ae'     => array( '%e2%80%ae' ),
+			'only %ef%bb%bf'     => array( '%ef%bb%bf' ),
+
+			// Non-visible characters within the title.
+			'in middle of title' => array(
+				'title'    => 'Nonvisible %ef%bb%bfin middle of title',
+				'expected' => 'nonvisible-in-middle-of-title',
+			),
+			'at start of title'  => array(
+				'title'    => '%e2%80%8bNonvisible at start of title',
+				'expected' => 'nonvisible-at-start-of-title',
+			),
+			'at end of title'    => array(
+				'title'    => 'Nonvisible at end of title %e2%80%8b',
+				'expected' => 'nonvisible-at-end-of-title',
+			),
+			'randomly in title'  => array(
+				'title'    => 'Nonvisible%ef%bb%bf %e2%80%aerandomly %e2%80%8ein the %e2%80%8e title%e2%80%8e',
+				'expected' => 'nonvisible-randomly-in-the-title',
+			),
+		);
+	}
+
+	/**
+	 * @ticket 47912
+	 * @dataProvider data_non_visible_characters_without_width_when_not_save
+	 *
+	 * @param string $title     The title to be sanitized.
+	 * @param string $expected  Expected sanitized title.
+	 */
+	public function test_non_visible_characters_without_width_when_not_save( $title, $expected = '' ) {
+		$this->assertSame( $expected, sanitize_title_with_dashes( $title ) );
+	}
+
+	/**
+	 * Data provider.
+	 *
+	 * @return array
+	 */
+	public function data_non_visible_characters_without_width_when_not_save() {
+		return array(
+			// Just the non-visible characters.
+			'only %e2%80%8b'     => array( '%e2%80%8b', '%e2%80%8b' ),
+			'only %e2%80%8c'     => array( '%e2%80%8c', '%e2%80%8c' ),
+			'only %e2%80%8d'     => array( '%e2%80%8d', '%e2%80%8d' ),
+			'only %e2%80%8e'     => array( '%e2%80%8e', '%e2%80%8e' ),
+			'only %e2%80%8f'     => array( '%e2%80%8f', '%e2%80%8f' ),
+			'only %e2%80%aa'     => array( '%e2%80%aa', '%e2%80%aa' ),
+			'only %e2%80%ab'     => array( '%e2%80%ab', '%e2%80%ab' ),
+			'only %e2%80%ac'     => array( '%e2%80%ac', '%e2%80%ac' ),
+			'only %e2%80%ad'     => array( '%e2%80%ad', '%e2%80%ad' ),
+			'only %e2%80%ae'     => array( '%e2%80%ae', '%e2%80%ae' ),
+			'only %ef%bb%bf'     => array( '%ef%bb%bf', '%ef%bb%bf' ),
+
+			// Non-visible characters within the title.
+			'in middle of title' => array(
+				'title'    => 'Nonvisible %ef%bb%bfin middle of title',
+				'expected' => 'nonvisible-%ef%bb%bfin-middle-of-title',
+			),
+			'at start of title'  => array(
+				'title'    => '%e2%80%8bNonvisible at start of title',
+				'expected' => '%e2%80%8bnonvisible-at-start-of-title',
+			),
+			'at end of title'    => array(
+				'title'    => 'Nonvisible at end of title %e2%80%8b',
+				'expected' => 'nonvisible-at-end-of-title-%e2%80%8b',
+			),
+			'randomly in title'  => array(
+				'title'    => 'Nonvisible%ef%bb%bf %e2%80%aerandomly %e2%80%8ein the %e2%80%8e title%e2%80%8e',
+				'expected' => 'nonvisible%ef%bb%bf-%e2%80%aerandomly-%e2%80%8ein-the-%e2%80%8e-title%e2%80%8e',
+			),
+		);
+	}
+
+	/**
+	 * @ticket 47912
+	 * @dataProvider data_converts_non_visible_characters_with_width_to_hyphen
+	 *
+	 * @param string $title     The title to be sanitized.
+	 * @param string $expected  Expected sanitized title.
+	 */
+	public function test_converts_non_visible_characters_with_width_to_hyphen( $title, $expected = '' ) {
+		$this->assertSame( $expected, sanitize_title_with_dashes( $title, '', 'save' ) );
+	}
+
+	/**
+	 * Data provider.
+	 *
+	 * @return array
+	 */
+	public function data_converts_non_visible_characters_with_width_to_hyphen() {
+		return array(
+			// Only the non-visible characters.
+			'only %e2%80%80'     => array( '%e2%80%80' ),
+			'only %e2%80%81'     => array( '%e2%80%81' ),
+			'only %e2%80%82'     => array( '%e2%80%82' ),
+			'only %e2%80%83'     => array( '%e2%80%83' ),
+			'only %e2%80%84'     => array( '%e2%80%84' ),
+			'only %e2%80%85'     => array( '%e2%80%85' ),
+			'only %e2%80%86'     => array( '%e2%80%86' ),
+			'only %e2%80%87'     => array( '%e2%80%87' ),
+			'only %e2%80%88'     => array( '%e2%80%88' ),
+			'only %e2%80%89'     => array( '%e2%80%89' ),
+			'only %e2%80%8a'     => array( '%e2%80%8a' ),
+			'only %e2%80%a8'     => array( '%e2%80%a8' ),
+			'only %e2%80%a9'     => array( '%e2%80%a9' ),
+			'only %e2%80%af'     => array( '%e2%80%af' ),
+
+			// Non-visible characters within the title.
+			'in middle of title' => array(
+				'title'    => 'Nonvisible %e2%80%82 in middle of title',
+				'expected' => 'nonvisible-in-middle-of-title',
+			),
+			'at start of title'  => array(
+				'title'    => '%e2%80%83Nonvisible at start of title',
+				'expected' => 'nonvisible-at-start-of-title',
+			),
+			'at end of title'    => array(
+				'title'    => 'Nonvisible at end of title %e2%80%81',
+				'expected' => 'nonvisible-at-end-of-title',
+			),
+			'two end of title'   => array(
+				'title'    => 'Nonvisible at end of title %e2%80%81 %e2%80%af',
+				'expected' => 'nonvisible-at-end-of-title',
+			),
+			'randomly in title'  => array(
+				'title'    => 'Nonvisible%e2%80%80 %e2%80%a9randomly %e2%80%87in the %e2%80%a8 title%e2%80%af',
+				'expected' => 'nonvisible-randomly-in-the-title',
+			),
+		);
+	}
+
+	/**
+	 * @ticket 47912
+	 * @dataProvider data_non_visible_characters_with_width_to_hyphen_when_not_save
+	 *
+	 * @param string $title     The title to be sanitized.
+	 * @param string $expected  Expected sanitized title.
+	 */
+	public function test_non_visible_characters_with_width_to_hyphen_when_not_save( $title, $expected = '' ) {
+		$this->assertSame( $expected, sanitize_title_with_dashes( $title ) );
+	}
+
+	/**
+	 * Data provider.
+	 *
+	 * @return array
+	 */
+	public function data_non_visible_characters_with_width_to_hyphen_when_not_save() {
+		return array(
+			// Just the non-visible characters.
+			'only %e2%80%8b'     => array( '%e2%80%8b', '%e2%80%8b' ),
+			'only %e2%80%8c'     => array( '%e2%80%8c', '%e2%80%8c' ),
+			'only %e2%80%8d'     => array( '%e2%80%8d', '%e2%80%8d' ),
+			'only %e2%80%8e'     => array( '%e2%80%8e', '%e2%80%8e' ),
+			'only %e2%80%8f'     => array( '%e2%80%8f', '%e2%80%8f' ),
+			'only %e2%80%aa'     => array( '%e2%80%aa', '%e2%80%aa' ),
+			'only %e2%80%ab'     => array( '%e2%80%ab', '%e2%80%ab' ),
+			'only %e2%80%ac'     => array( '%e2%80%ac', '%e2%80%ac' ),
+			'only %e2%80%ad'     => array( '%e2%80%ad', '%e2%80%ad' ),
+			'only %e2%80%ae'     => array( '%e2%80%ae', '%e2%80%ae' ),
+			'only %ef%bb%bf'     => array( '%ef%bb%bf', '%ef%bb%bf' ),
+
+			// Non-visible characters within the title.
+			'in middle of title' => array(
+				'title'    => 'Nonvisible %e2%80%82 in middle of title',
+				'expected' => 'nonvisible-%e2%80%82-in-middle-of-title',
+			),
+			'at start of title'  => array(
+				'title'    => '%e2%80%83Nonvisible at start of title',
+				'expected' => '%e2%80%83nonvisible-at-start-of-title',
+			),
+			'at end of title'    => array(
+				'title'    => 'Nonvisible at end of title %e2%80%81',
+				'expected' => 'nonvisible-at-end-of-title-%e2%80%81',
+			),
+			'randomly in title'  => array(
+				'title'    => 'Nonvisible%e2%80%80 %e2%80%aerandomly %e2%80%87in the %e2%80%a8 title%e2%80%af',
+				'expected' => 'nonvisible%e2%80%80-%e2%80%aerandomly-%e2%80%87in-the-%e2%80%a8-title%e2%80%af',
+			),
+		);
+	}
 }