Code Modernization: Rename parameters that use reserved keywords in phpunit/tests/compat/mbSubstr.php.

While using reserved PHP keywords as parameter name labels is allowed, in the context of function calls using named parameters in PHP 8.0+, this will easily lead to confusion. To avoid that, it is recommended not to use reserved keywords as function parameter names.

This commit renames the `$string` parameter to `$input_string` in the unit tests for `mb_substr()` polyfill.

Follow-up to [52946], [52996], [52997], [52998], [53003], [53014], [53029], [53039], [53116], [53117], [53137], [53174], [53184], [53185], [53192], [53193], [53198], [53203], [53207], [53215], [53216], [53220], [53230], [53232], [53236], [53239], [53240], [53242], [53243], [53245], [53246], [53257], [53269], [53270], [53271], [53272], [53273], [53274], [53275], [53276], [53277], [53281], [53283], [53284], [53285], [53287], [53364], [53365], [54927], [54929], [54930], [54931], [54932], [54933], [54938], [54943], [54944], [54945], [54946], [54947], [54948], [54950], [54951], [54952], [54956], [54959], [54960], [54961], [54962], [54964], [54965], [54969], [54970], [54971], [54972], [54996], [55000], [55011], [55013], [55014], [55015], [55016], [55017], [55020], [55021], [55023], [55027], [55028], [55034], [55036].

Props jrf, aristath, poena, justinahinon, SergeyBiryukov.
See #56788.

git-svn-id: https://develop.svn.wordpress.org/trunk@55037 602fd350-edb4-49c9-b593-d223f7449a82

Author: SergeyBiryukov

tests/phpunit/tests/compat/mbSubstr.php

@@ -19,24 +19,24 @@ public function test_mb_substr_availability() {
 	/**
 	 * @dataProvider utf8_substrings
 	 */
-	public function test_mb_substr( $string, $start, $length, $expected_character_substring ) {
-		$this->assertSame( $expected_character_substring, _mb_substr( $string, $start, $length, 'UTF-8' ) );
+	public function test_mb_substr( $input_string, $start, $length, $expected_character_substring ) {
+		$this->assertSame( $expected_character_substring, _mb_substr( $input_string, $start, $length, 'UTF-8' ) );
 	}
 
 	/**
 	 * @dataProvider utf8_substrings
 	 */
-	public function test_mb_substr_via_regex( $string, $start, $length, $expected_character_substring ) {
+	public function test_mb_substr_via_regex( $input_string, $start, $length, $expected_character_substring ) {
 		_wp_can_use_pcre_u( false );
-		$this->assertSame( $expected_character_substring, _mb_substr( $string, $start, $length, 'UTF-8' ) );
+		$this->assertSame( $expected_character_substring, _mb_substr( $input_string, $start, $length, 'UTF-8' ) );
 		_wp_can_use_pcre_u( 'reset' );
 	}
 
 	/**
 	 * @dataProvider utf8_substrings
 	 */
-	public function test_8bit_mb_substr( $string, $start, $length, $expected_character_substring, $expected_byte_substring ) {
-		$this->assertSame( $expected_byte_substring, _mb_substr( $string, $start, $length, '8bit' ) );
+	public function test_8bit_mb_substr( $input_string, $start, $length, $expected_character_substring, $expected_byte_substring ) {
+		$this->assertSame( $expected_byte_substring, _mb_substr( $input_string, $start, $length, '8bit' ) );
 	}
 
 	/**
@@ -47,49 +47,49 @@ public function test_8bit_mb_substr( $string, $start, $length, $expected_charact
 	public function utf8_substrings() {
 		return array(
 			array(
-				'string'                       => 'баба',
+				'input_string'                 => 'баба',
 				'start'                        => 0,
 				'length'                       => 3,
 				'expected_character_substring' => 'баб',
 				'expected_byte_substring'      => "б\xD0",
 			),
 			array(
-				'string'                       => 'баба',
+				'input_string'                 => 'баба',
 				'start'                        => 0,
 				'length'                       => -1,
 				'expected_character_substring' => 'баб',
 				'expected_byte_substring'      => "баб\xD0",
 			),
 			array(
-				'string'                       => 'баба',
+				'input_string'                 => 'баба',
 				'start'                        => 1,
 				'length'                       => null,
 				'expected_character_substring' => 'аба',
 				'expected_byte_substring'      => "\xB1аба",
 			),
 			array(
-				'string'                       => 'баба',
+				'input_string'                 => 'баба',
 				'start'                        => -3,
 				'length'                       => null,
 				'expected_character_substring' => 'аба',
 				'expected_byte_substring'      => "\xB1а",
 			),
 			array(
-				'string'                       => 'баба',
+				'input_string'                 => 'баба',
 				'start'                        => -3,
 				'length'                       => 2,
 				'expected_character_substring' => 'аб',
 				'expected_byte_substring'      => "\xB1\xD0",
 			),
 			array(
-				'string'                       => 'баба',
+				'input_string'                 => 'баба',
 				'start'                        => -1,
 				'length'                       => 2,
 				'expected_character_substring' => 'а',
 				'expected_byte_substring'      => "\xB0",
 			),
 			array(
-				'string'                       => 'I am your баба',
+				'input_string'                 => 'I am your баба',
 				'start'                        => 0,
 				'length'                       => 11,
 				'expected_character_substring' => 'I am your б',