inflector

src/Inflector.php

@@ -496,11 +496,15 @@ public function toSentence(string $input, bool $uppercaseAll = false): string
      */
     public function toWords(string $input): string
     {
-        return mb_strtolower(trim(str_replace([
-            '-',
-            '_',
-            '.',
-        ], ' ', preg_replace('/(?<!\p{Lu})(\p{Lu})|(\p{Lu})(?=\p{Ll})/u', ' \0', $input))));
+        /**
+         * @var string $words We assume that `$input` is valid UTF-8 string, so `preg_replace()` never returns `false`.
+         */
+        $words = preg_replace('/(?<!\p{Lu})(\p{Lu})|(\p{Lu})(?=\p{Ll})/u', ' \0', $input);
+        return mb_strtolower(
+            trim(
+                str_replace(['-', '_', '.'], ' ', $words)
+            )
+        );
     }
 
     /**
@@ -520,6 +524,10 @@ public function pascalCaseToId(string $input, string $separator = '-', bool $str
             ? '/(?<=\p{L})(\p{Lu})/u'
             : '/(?<=\p{L})(?<!\p{Lu})(\p{Lu})/u';
 
+        /**
+         * @var string $result We assume that `$separator` and `$input` are valid UTF-8 strings, so `preg_replace()`
+         * never returns `false`.
+         */
         $result = preg_replace($regex, addslashes($separator) . '\1', $input);
 
         if ($separator !== '_') {
@@ -544,10 +552,14 @@ public function pascalCaseToId(string $input, string $separator = '-', bool $str
      */
     public function toPascalCase(string $input): string
     {
+        /**
+         * @var string $input We assume that `$input` is valid UTF-8 string, so `preg_replace()` never returns `false`.
+         */
+        $input = preg_replace('/[^\pL\pN]+/u', ' ', $input);
         return str_replace(
             ' ',
             '',
-            StringHelper::uppercaseFirstCharacterInEachWord(preg_replace('/[^\pL\pN]+/u', ' ', $input)),
+            StringHelper::uppercaseFirstCharacterInEachWord($input),
         );
     }
 
@@ -556,12 +568,14 @@ public function toPascalCase(string $input): string
      *
      * @param string $input The string to humanize.
      * @param bool $uppercaseWords Whether to set all words to uppercase or not.
-     *
-     * @return string
      */
     public function toHumanReadable(string $input, bool $uppercaseWords = false): string
     {
-        $input = str_replace('_', ' ', preg_replace('/_id$/', '', $input));
+        /**
+         * @var string $input We assume that `$input` is valid UTF-8 string, so `preg_replace()` never returns `false`.
+         */
+        $input = preg_replace('/_id$/', '', $input);
+        $input = str_replace('_', ' ', $input);
 
         return $uppercaseWords
             ? StringHelper::uppercaseFirstCharacterInEachWord($input)
@@ -600,7 +614,11 @@ public function toCamelCase(string $input): string
      */
     public function toSnakeCase(string $input, bool $strict = true): string
     {
-        return $this->pascalCaseToId(preg_replace('/[^\pL\pN]+/u', '_', $input), '_', $strict);
+        /**
+         * @var string $input We assume that `$input` is valid UTF-8 string, so `preg_replace()` never returns `false`.
+         */
+        $input = preg_replace('/[^\pL\pN]+/u', '_', $input);
+        return $this->pascalCaseToId($input, '_', $strict);
     }
 
     /**
@@ -646,9 +664,21 @@ public function tableToClass(string $tableName): string
     public function toSlug(string $input, string $replacement = '-', bool $lowercase = true): string
     {
         $quotedReplacement = preg_quote($replacement, '/');
-        // replace all non words character
+
+        /**
+         * Replace all non-words character
+         *
+         * @var string $input We assume that `$input` and `$replacement` are valid UTF-8 strings, so `preg_replace()`
+         * never returns `false`.
+         */
         $input = preg_replace('/[^a-zA-Z0-9]+/u', $replacement, $this->toTransliterated($input));
-        // remove first and last replacements
+
+        /**
+         * Remove first and last replacements
+         *
+         * @var string $input We assume that `$input` and `$quotedReplacement` are valid UTF-8 strings, so
+         * `preg_replace()` never returns `false`.
+         */
         $input = preg_replace(
             "/^(?:$quotedReplacement)+|(?:$quotedReplacement)+$/u" . ($lowercase ? 'i' : ''),
             '',
@@ -671,8 +701,6 @@ public function toSlug(string $input, string $replacement = '-', bool $lowercase
      * @param string|Transliterator|null $transliterator either a {@see \Transliterator} or a string
      * from which a {@see \Transliterator} can be built. If null, value set with {@see withTransliterator()}
      * or {@see TRANSLITERATE_LOOSE} is used.
-     *
-     * @return string
      */
     public function toTransliterated(string $input, $transliterator = null): string
     {
@@ -681,7 +709,11 @@ public function toTransliterated(string $input, $transliterator = null): string
                 $transliterator = $this->transliterator;
             }
 
-            /* @noinspection PhpComposerExtensionStubsInspection */
+            /**
+             * @noinspection PhpComposerExtensionStubsInspection
+             * @var string We assume that `$input` are valid UTF-8 strings and `$transliterator` is valid, so
+             * `preg_replace()` never returns `false`.
+             */
             return transliterator_transliterate($transliterator, $input);
         }