Fix variation of #33 "The start position cannot exceed initial string length"

Author: thekid

src/main/php/lang/types/String.class.php

@@ -273,7 +273,7 @@ public function startsWith($arg) {
   public function endsWith($arg) {
     $bytes= $this->asIntern($arg);
     $l= strlen($bytes);
-    return $l > 0 && 0 === substr_compare($this->buffer, $bytes, -$l, $l);
+    return $l > 0 && $l <= $this->length && 0 === substr_compare($this->buffer, $bytes, -$l, $l);
   }
 
   /**

src/test/php/net/xp_framework/unittest/core/types/StringTest.class.php

@@ -158,6 +158,11 @@ public function does_not_start_with_empty_string() {
     $this->assertFalse((new String('test'))->startsWith(''));
   }
 
+  #[@test, @values(['', 'test'])]
+  public function empty_string_does_not_start_with_anything($value) {
+    $this->assertFalse(String::$EMPTY->startsWith($value));
+  }
+
   #[@test]
   public function endsWith() {
     $str= new String('www.müller.com');
@@ -172,6 +177,11 @@ public function does_not_end_with_empty_string() {
     $this->assertFalse((new String('test'))->endsWith(''));
   }
 
+  #[@test, @values(['', 'test'])]
+  public function empty_string_does_not_end_with_anything($value) {
+    $this->assertFalse(String::$EMPTY->endsWith($value));
+  }
+
   #[@test]
   public function concat() {
     $this->assertEquals(new String('www.müller.com'), (new String('www'))