Add Str helper library

Tests included.

Methods include:
startsWith()
endsWith()
equals()

Author: iamface

src/Str.php

@@ -0,0 +1,69 @@
+<?php declare(strict_types = 1);
+namespace Noname\Common;
+
+/**
+ * Class Str
+ *
+ * @package Noname\Common
+ */
+class Str
+{
+    /**
+     * Checks if string starts with given prefix.
+     *
+     * By default this method is case-sensitive.
+     *
+     * @param string $string
+     * @param string $prefix
+     * @param bool $caseSensitive
+     * @return bool
+     */
+    public static function startsWith(string $string, string $prefix, bool $caseSensitive = true): bool
+    {
+        if ($caseSensitive) {
+            return strpos($string, $prefix) === 0;
+        } else {
+            return stripos($string, $prefix) === 0;
+        }
+    }
+
+    /**
+     * Checks if string ends with given prefix.
+     *
+     * By default this method is case-sensitive.
+     *
+     * @param string $string
+     * @param string $suffix
+     * @param bool $caseSensitive
+     * @return bool
+     */
+    public static function endsWith(string $string, string $suffix, bool $caseSensitive = true): bool
+    {
+        $ending = strlen($string)-strlen($suffix);
+
+        if ($caseSensitive) {
+            return strrpos($string, $suffix) === $ending;
+        } else {
+            return strripos($string, $suffix) === $ending;
+        }
+    }
+
+    /**
+     * Checks if two strings equal each other.
+     *
+     * By default this method is case-sensitive.
+     *
+     * @param string $a
+     * @param string $b
+     * @param bool $caseSensitive
+     * @return bool
+     */
+    public static function equals(string $a, string $b, bool $caseSensitive = true): bool
+    {
+        if ($caseSensitive) {
+            return $a === $b;
+        } else {
+            return strtolower($a) === strtolower($b);
+        }
+    }
+}

tests/StrTest.php

@@ -0,0 +1,47 @@
+<?php declare(strict_types=1);
+namespace Noname\Common;
+
+class StrTest extends \PHPUnit_Framework_TestCase
+{
+    /**
+     * @covers Str::testStartsWith
+     */
+    public function testStartsWith()
+    {
+        $caseSensitiveTrue  = Str::startsWith('Case-sensitive', 'C');
+        $caseSensitiveFalse = Str::startsWith('Case-sensitive', 'c');
+        $caseInsensitive    = Str::startsWith('case-insensitive', 'C', false);
+
+        $this->assertTrue($caseSensitiveTrue);
+        $this->assertFalse($caseSensitiveFalse);
+        $this->assertTrue($caseInsensitive);
+    }
+
+    /**
+     * @covers Str::testEndsWidth
+     */
+    public function testEndsWidth()
+    {
+        $caseSensitiveTrue  = Str::endsWith('sensitive-End', 'End');
+        $caseSensitiveFalse = Str::endsWith('sensitive-End', 'end');
+        $caseInsensitive    = Str::endsWith('insensitive-end', 'End', false);
+
+        $this->assertTrue($caseSensitiveTrue);
+        $this->assertFalse($caseSensitiveFalse);
+        $this->assertTrue($caseInsensitive);
+    }
+
+    /**
+     * @covers Str::equals
+     */
+    public function testEquals()
+    {
+        $caseSensitiveTrue  = Str::equals('case-sensitive', 'case-sensitive');
+        $caseSensitiveFalse = Str::equals('case-sensitive', 'Case-sensitive');
+        $caseInsensitive    = Str::equals('case-insensitive', 'Case-insensitive', false);
+
+        $this->assertTrue($caseSensitiveTrue);
+        $this->assertFalse($caseSensitiveFalse);
+        $this->assertTrue($caseInsensitive);
+    }
+}