1 files changed, 143 insertions, 0 deletions
diff --git a/tests/phpunit/includes/StringUtilsTest.php b/tests/phpunit/includes/StringUtilsTest.php
new file mode 100644
index 00000000..db3d2655
--- /dev/null
+++ b/tests/phpunit/includes/StringUtilsTest.php
@@ -0,0 +1,143 @@
+<?php
+
+class StringUtilsTest extends MediaWikiTestCase {
+
+	/**
+	 * This test StringUtils::isUtf8 whenever we have mbstring extension
+	 * loaded.
+	 *
+	 * @covers StringUtils::isUtf8
+	 * @dataProvider provideStringsForIsUtf8Check
+	 */
+	function testIsUtf8WithMbstring( $expected, $string ) {
+		if ( !function_exists( 'mb_check_encoding' ) ) {
+			$this->markTestSkipped( 'Test requires the mbstring PHP extension' );
+		}
+		$this->assertEquals( $expected,
+			StringUtils::isUtf8( $string ),
+			'Testing string "' . $this->escaped( $string ) . '" with mb_check_encoding'
+		);
+	}
+
+	/**
+	 * This test StringUtils::isUtf8 making sure we use the pure PHP
+	 * implementation used as a fallback when mb_check_encoding() is
+	 * not available.
+	 *
+	 * @covers StringUtils::isUtf8
+	 * @dataProvider provideStringsForIsUtf8Check
+	 */
+	function testIsUtf8WithPhpFallbackImplementation( $expected, $string ) {
+		$this->assertEquals( $expected,
+			StringUtils::isUtf8( $string, /** disable mbstring: */ true ),
+			'Testing string "' . $this->escaped( $string ) . '" with pure PHP implementation'
+		);
+	}
+
+	/**
+	 * Print high range characters as an hexadecimal
+	 */
+	function escaped( $string ) {
+		$escaped = '';
+		$length = strlen( $string );
+		for ( $i = 0; $i < $length; $i++ ) {
+			$char = $string[$i];
+			$val = ord( $char );
+			if ( $val > 127 ) {
+				$escaped .= '\x' . dechex( $val );
+			} else {
+				$escaped .= $char;
+			}
+		}
+		return $escaped;
+	}
+
+	/**
+	 * See also "UTF-8 decoder capability and stress test" by
+	 * Markus Kuhn:
+	 * http://www.cl.cam.ac.uk/~mgk25/ucs/examples/UTF-8-test.txt
+	 */
+	function provideStringsForIsUtf8Check() {
+		// Expected return values for StringUtils::isUtf8()
+		$PASS = true;
+		$FAIL = false;
+
+		return array(
+			array( $PASS, 'Some ASCII' ),
+			array( $PASS, "Euro sign €" ),
+
+			# First possible sequences
+			array( $PASS, "\x00" ),
+			array( $PASS, "\xc2\x80" ),
+			array( $PASS, "\xe0\xa0\x80" ),
+			array( $PASS, "\xf0\x90\x80\x80" ),
+			array( $PASS, "\xf8\x88\x80\x80\x80" ),
+			array( $PASS, "\xfc\x84\x80\x80\x80\x80" ),
+
+			# Last possible sequence
+			array( $PASS, "\x7f" ),
+			array( $PASS, "\xdf\xbf" ),
+			array( $PASS, "\xef\xbf\xbf" ),
+			array( $PASS, "\xf7\xbf\xbf\xbf" ),
+			array( $PASS, "\xfb\xbf\xbf\xbf\xbf" ),
+			array( $FAIL, "\xfd\xbf\xbf\xbf\xbf\xbf" ),
+
+			# boundaries:
+			array( $PASS, "\xed\x9f\xbf" ),
+			array( $PASS, "\xee\x80\x80" ),
+			array( $PASS, "\xef\xbf\xbd" ),
+			array( $PASS, "\xf4\x8f\xbf\xbf" ),
+			array( $PASS, "\xf4\x90\x80\x80" ),
+
+			# Malformed
+			array( $FAIL, "\x80" ),
+			array( $FAIL, "\xBF" ),
+			array( $FAIL, "\x80\xbf" ),
+			array( $FAIL, "\x80\xbf\x80" ),
+			array( $FAIL, "\x80\xbf\x80\xbf" ),
+			array( $FAIL, "\x80\xbf\x80\xbf\x80" ),
+			array( $FAIL, "\x80\xbf\x80\xbf\x80\xbf" ),
+			array( $FAIL, "\x80\xbf\x80\xbf\x80\xbf\x80" ),
+
+			# last byte missing
+			array( $FAIL, "\xc0" ),
+			array( $FAIL, "\xe0\x80" ),
+			array( $FAIL, "\xf0\x80\x80" ),
+			array( $FAIL, "\xf8\x80\x80\x80" ),
+			array( $FAIL, "\xfc\x80\x80\x80\x80" ),
+			array( $FAIL, "\xdf" ),
+			array( $FAIL, "\xef\xbf" ),
+			array( $FAIL, "\xf7\xbf\xbf" ),
+			array( $FAIL, "\xfb\xbf\xbf\xbf" ),
+			array( $FAIL, "\xfd\xbf\xbf\xbf\xbf" ),
+
+			# impossible bytes
+			array( $FAIL, "\xfe" ),
+			array( $FAIL, "\xff" ),
+			array( $FAIL, "\xfe\xfe\xff\xff" ),
+
+			/**
+			# The PHP implementation does not handle characters
+			# being represented in a form which is too long :(
+
+			# overlong sequences
+			array( $FAIL, "\xc0\xaf" ),
+			array( $FAIL, "\xe0\x80\xaf" ),
+			array( $FAIL, "\xf0\x80\x80\xaf" ),
+			array( $FAIL, "\xf8\x80\x80\x80\xaf" ),
+			array( $FAIL, "\xfc\x80\x80\x80\x80\xaf" ),
+
+			# Maximum overlong sequences
+			array( $FAIL, "\xc1\xbf" ),
+			array( $FAIL, "\xe0\x9f\xbf" ),
+			array( $FAIL, "\xf0\x8F\xbf\xbf" ),
+			array( $FAIL, "\xf8\x87\xbf\xbf" ),
+			array( $FAIL, "\xfc\x83\xbf\xbf\xbf\xbf" ),
+			**/
+
+			# non characters
+			array( $PASS, "\xef\xbf\xbe" ),
+			array( $PASS, "\xef\xbf\xbf" ),
+		);
+	}
+}