Index: tests/t3lib/t3lib_divTest.php
===================================================================
--- tests/t3lib/t3lib_divTest.php	(revision 8127)
+++ tests/t3lib/t3lib_divTest.php	(working copy)
@@ -1542,5 +1542,81 @@
 
 		rmdir($directory);
 	}
+
+	/**
+	 * Data provider for checkIsFirstPartOfStrReturnsTrueForMatchingFirstParts
+	 *
+	 * @return array
+	 */
+	public function matchingFirstPartsDataProvider() {
+		return array(
+			'hello world/hello' => array('hello world', 'hello'),
+			'hello/hello' => array('hello', 'hello'),
+
+		);
+	}
+
+	/**
+	 * Data provider for checkIsFirstPartOfStrReturnsFalseForNotMatchingFirstParts
+	 *
+	 * @return array
+	 */
+	public function notMatchingFirstPartsDataProvider() {
+		return array(
+			'hello/bye' => array('hello', 'bye'),
+			'bye/hello' => array('bye', 'hello'),
+			'string/array' => array('string', array()),
+			'array/string' => array(array(), 'string'),
+			'string/null' => array('string', NULL),
+			'null/string' => array(NULL, 'string'),
+			'array/null' => array(array(), NULL),
+			'null/array' => array(NULL, array()),
+			'empty strings' => array('', ''),
+			'empty string/null' => array('', NULL),
+			'empty string/false' => array('', FALSE),
+			'null/empty string' => array(NULL, ''),
+			'false/empty string' => array(FALSE, ''),
+			'zero/empty string' => array(0, ''),
+			'null/zero' => array(NULL, 0),
+			'empty string/zero' => array('', 0),
+			'string/integer' => array('24', 24),
+			'integer/string' => array(24, '24'),
+			'string/integer as first part' => array('24 Bier bitte', 24)
+		);
+	}
+
+	/**
+	 * Checks if t3lib_div::isFirstPartOfStr returns true for a set of matching
+	 * string/firstParts.
+	 *
+	 * @test
+	 * @see t3lib_div::isFirstPartOfStr
+	 * @dataProvider matchingFirstPartsDataProvider
+	 */
+	public function checkIsFirstPartOfStrReturnsTrueForMatchingFirstParts($str, $partStr) {
+		$this->assertTrue(t3lib_div::isFirstPartOfStr($str, $partStr));
+	}
+
+	/**
+	 * Checks if t3lib_div::isFirstPartOfStr returns false for a not matching
+	 * pair of string and firstPart.
+	 *
+	 * @test
+	 * @see t3lib_div::isFirstPartOfStr
+	 * @dataProvider notMatchingFirstPartsDataProvider
+	 */
+	public function checkIsFirstPartOfStrReturnsFalseForNotMatchingFirstParts($str, $partStr) {
+		$this->assertFalse(t3lib_div::isFirstPartOfStr($str, $partStr));
+	}
+
+	/**
+	 * Checks if t3lib_div::isFirstPartOfStr works case sensitive.
+	 *
+	 * @test
+	 * @see t3lib_div::isFirstPartOfStr
+	 */
+	public function checkIsFirstPartOfStrWorksCaseSensitive($str, $partStr) {
+		$this->assertFalse(t3lib_div::isFirstPartOfStr('hello world', 'Hello'));
+	}
 }
 ?>
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