Added Str::camelCase(), Str::studlyCase(), Str::pascalCase, Str::snakeCase() and Str::kebabCase() methods

Author: PHLAK

README.md

@@ -1047,6 +1047,91 @@ $string->decrypt('secret'); // Returns 'john pinkerton'
 
 ---
 
+### camelCase
+> Convert the string to camelCase.
+
+```php
+Twine\Str::camelCase( void ) : Twine\Str
+```
+
+#### Example
+
+```php
+$string = new Twine\Str('john pinkerton');
+
+$string->camelCase(); // Returns 'johnPinkerton'
+```
+
+---
+
+### studlyCase
+> Convert the string to studlyCase.
+
+```php
+Twine\Str::studlyCase( void ) : Twine\Str
+```
+
+#### Example
+
+```php
+$string = new Twine\Str('john pinkerton');
+
+$string->studlyCase(); // Returns 'JohnPinkerton'
+```
+
+---
+
+### pascalCase
+> Convert the string to pascalCase.
+
+```php
+Twine\Str::pascalCase( void ) : Twine\Str
+```
+
+#### Example
+
+```php
+$string = new Twine\Str('john pinkerton');
+
+$string->pascalCase(); // Returns 'JohnPinkerton'
+```
+
+---
+
+### snakeCase
+> Convert the string to snakeCase.
+
+```php
+Twine\Str::snakeCase( void ) : Twine\Str
+```
+
+#### Example
+
+```php
+$string = new Twine\Str('john pinkerton');
+
+$string->snakeCase(); // Returns 'john_pinkerton'
+```
+
+---
+
+### kebabCase
+> Convert the string to kebabCase.
+
+```php
+Twine\Str::kebabCase( void ) : Twine\Str
+```
+
+#### Example
+
+```php
+$string = new Twine\Str('john pinkerton');
+
+$string->kebabCase(); // Returns 'john-pinkerton'
+```
+
+---
+
 ## Chaining Methods
 
 A Twine string can be manipulated fluently by chaining methods. Here are a few

src/Str.php

@@ -4,6 +4,7 @@
 
 use PHLAK\Twine\Traits\Aliases;
 use PHLAK\Twine\Traits\ArrayAccess;
+use PHLAK\Twine\Traits\Caseable;
 use PHLAK\Twine\Traits\Comparable;
 use PHLAK\Twine\Traits\Convenience;
 use PHLAK\Twine\Traits\Encodable;
@@ -16,6 +17,7 @@ class Str implements \ArrayAccess, \JsonSerializable, \Serializable
 {
     use Aliases,
         ArrayAccess,
+        Caseable,
         Comparable,
         Convenience,
         Encodable,

src/Traits/Caseable.php

@@ -0,0 +1,72 @@
+<?php
+
+namespace PHLAK\Twine\Traits;
+
+trait Caseable
+{
+    /**
+     * Convert the string to camelCase.
+     *
+     * @return self
+     */
+    public function camelCase() : self
+    {
+        $words = array_map(function ($word) {
+            return ucfirst(strtolower($word));
+        }, $this->words());
+
+        return new static(lcfirst(implode('', $words)));
+    }
+
+    /**
+     * Convert the string to StudlyCase.
+     *
+     * @return self
+     */
+    public function studlyCase() : self
+    {
+        $words = array_map(function ($word) {
+            return ucfirst(strtolower($word));
+        }, $this->words());
+
+        return new static(implode('', $words));
+    }
+
+    /**
+     * Convert the string to PascalCase.
+     *
+     * @return self
+     */
+    public function pascalCase() : self
+    {
+        return $this->studlyCase();
+    }
+
+    /**
+     * Convert the string to snake_case.
+     *
+     * @return self
+     */
+    public function snakeCase() : self
+    {
+        $words = array_map(function ($word) {
+            return strtolower($word);
+        }, $this->words());
+
+        return new static(implode('_', $words));
+    }
+
+    /**
+     * Convert the string to kebab-case.
+     *
+     * @return self
+     */
+    public function kebabCase() : self
+    {
+        $words = array_map(function ($word) {
+            return strtolower($word);
+        }, $this->words());
+
+        return new static(implode('-', $words));
+    }
+}

tests/CaseableTest.php

@@ -0,0 +1,54 @@
+<?php
+
+namespace PHLAK\Twine\Tests;
+
+use PHLAK\Twine;
+use PHPUnit\Framework\TestCase;
+
+class CaseableTest extends TestCase
+{
+    public function test_it_can_convert_to_camel_case()
+    {
+        $string = new Twine\Str('john pinkerton');
+
+        $camelCase = $string->camelCase();
+
+        $this->assertEquals('johnPinkerton', $camelCase);
+    }
+
+    public function test_it_can_convert_to_studly_case()
+    {
+        $string = new Twine\Str('john pinkerton');
+
+        $studlyCase = $string->studlyCase();
+
+        $this->assertEquals('JohnPinkerton', $studlyCase);
+    }
+
+    public function test_it_can_convert_to_pascal_case()
+    {
+        $string = new Twine\Str('john pinkerton');
+
+        $pascalCase = $string->pascalCase();
+
+        $this->assertEquals('JohnPinkerton', $pascalCase);
+    }
+
+    public function test_it_can_convert_to_snake_case()
+    {
+        $string = new Twine\Str('john pinkerton');
+
+        $snakeCase = $string->snakeCase();
+
+        $this->assertEquals('john_pinkerton', $snakeCase);
+    }
+
+    public function test_it_can_convert_to_kebab_case()
+    {
+        $string = new Twine\Str('john pinkerton');
+
+        $kebabCase = $string->kebabCase();
+
+        $this->assertEquals('john-pinkerton', $kebabCase);
+    }
+}