refactor: reduce_multiples() and fix user guide

system/Helpers/text_helper.php

@@ -526,9 +526,10 @@ function reduce_double_slashes(string $str): string
      */
     function reduce_multiples(string $str, string $character = ',', bool $trim = false): string
     {
-        $str = preg_replace('#' . preg_quote($character, '#') . '{2,}#', $character, $str);
+        $pattern = '#' . preg_quote($character, '#') . '{2,}#';
+        $str     = preg_replace($pattern, $character, $str);
 
-        return ($trim) ? trim($str, $character) : $str;
+        return $trim ? trim($str, $character) : $str;
     }
 }
 

tests/system/Helpers/TextHelperTest.php

@@ -15,6 +15,7 @@
 
 use CodeIgniter\Test\CIUnitTestCase;
 use InvalidArgumentException;
+use PHPUnit\Framework\Attributes\DataProvider;
 use PHPUnit\Framework\Attributes\Group;
 
 /**
@@ -82,24 +83,42 @@ public function testReduceDoubleSlashes(): void
         }
     }
 
-    public function testReduceMultiples(): void
+    #[DataProvider('provideReduceMultiples')]
+    public function testReduceMultiples(string $str, string $expected): void
     {
-        $strs = [
-            'Fred, Bill,, Joe, Jimmy' => 'Fred, Bill, Joe, Jimmy',
-            'Ringo, John, Paul,,'     => 'Ringo, John, Paul,',
-        ];
+        $this->assertSame($expected, reduce_multiples($str));
+    }
 
-        foreach ($strs as $str => $expect) {
-            $this->assertSame($expect, reduce_multiples($str));
-        }
-        $strs = [
-            'Fred, Bill,, Joe, Jimmy' => 'Fred, Bill, Joe, Jimmy',
-            'Ringo, John, Paul,,'     => 'Ringo, John, Paul',
+    /**
+     * @return iterable<string, list<string>>
+     */
+    public static function provideReduceMultiples(): iterable
+    {
+        yield from [
+            // string, expected
+            'double commas'            => ['Fred, Bill,, Joe, Jimmy', 'Fred, Bill, Joe, Jimmy'],
+            'double commas at last'    => ['Ringo, John, Paul,,', 'Ringo, John, Paul,'],
+            'commas at first and last' => [',Fred, Bill,, Joe, Jimmy,', ',Fred, Bill, Joe, Jimmy,'],
         ];
+    }
 
-        foreach ($strs as $str => $expect) {
-            $this->assertSame($expect, reduce_multiples($str, ',', true));
-        }
+    #[DataProvider('provideReduceMultiplesWithTrim')]
+    public function testReduceMultiplesWithTrim(string $str, string $expected): void
+    {
+        $this->assertSame($expected, reduce_multiples($str, ',', true));
+    }
+
+    /**
+     * @return iterable<string, list<string>>
+     */
+    public static function provideReduceMultiplesWithTrim(): iterable
+    {
+        yield from [
+            // string, expected
+            'double commas'            => ['Fred, Bill,, Joe, Jimmy', 'Fred, Bill, Joe, Jimmy'],
+            'double commas at last'    => ['Ringo, John, Paul,,', 'Ringo, John, Paul'],
+            'commas at first and last' => [',Fred, Bill,, Joe, Jimmy,', 'Fred, Bill, Joe, Jimmy'],
+        ];
     }
 
     public function testRandomString(): void

user_guide_src/source/helpers/text_helper.rst

@@ -127,7 +127,7 @@ The following functions are available:
         and handle string inputs. This however makes it just an
         alias for ``stripslashes()``.
 
-.. php:function:: reduce_multiples($str[, $character = ''[, $trim = false]])
+.. php:function:: reduce_multiples($str[, $character = ','[, $trim = false]])
 
     :param    string    $str: Text to search in
     :param    string    $character: Character to reduce
@@ -140,7 +140,7 @@ The following functions are available:
 
     .. literalinclude:: text_helper/009.php
 
-    If the third parameter is set to true it will remove occurrences of the
+    If the third parameter is set to ``true``, it will remove occurrences of the
     character at the beginning and the end of the string. Example:
 
     .. literalinclude:: text_helper/010.php

user_guide_src/source/helpers/text_helper/009.php

@@ -1,4 +1,4 @@
 <?php
 
 $string = 'Fred, Bill,, Joe, Jimmy';
-$string = reduce_multiples($string, ','); // results in "Fred, Bill, Joe, Jimmy"
+$string = reduce_multiples($string); // results in "Fred, Bill, Joe, Jimmy"

user_guide_src/source/helpers/text_helper/010.php

@@ -1,4 +1,4 @@
 <?php
 
 $string = ',Fred, Bill,, Joe, Jimmy,';
-$string = reduce_multiples($string, ', ', true); // results in "Fred, Bill, Joe, Jimmy"
+$string = reduce_multiples($string, ',', true); // results in "Fred, Bill, Joe, Jimmy"