Merge pull request #527 from scireum/feature/mko/SIRI-960-4

Strings.limit - Fixes IndexOutOfBoundsException for length values lesser than 1

src/main/java/sirius/kernel/commons/Strings.java

@@ -375,13 +375,13 @@ public static String limit(@Nullable Object input, int length) {
      * Limits the length of the given string to the given length.
      *
      * @param input        the object which string representation should be limited to the given length
-     * @param length       the max. number of characters to return
+     * @param length       the max. number of characters to return. Note: If the parameter is less than 1 an empty string is returned.
      * @param showEllipsis whether to append three dots if <tt>input</tt> is longer than <tt>length</tt>
      * @return a part of the string representation of the given <tt>input</tt>. If input is shorter
-     * than <tt>length</tt>, the full value is returned. If input is <tt>null</tt>, "" is returned.
+     * than <tt>length</tt>, the full value is returned. If input is <tt>null</tt> or empty, "" is returned. This also applies if <tt>length</tt> is less than 1.
      */
     public static String limit(@Nullable Object input, int length, boolean showEllipsis) {
-        if (isEmpty(input)) {
+        if (isEmpty(input) || length <= 0) {
             return "";
         }
         String str = String.valueOf(input).trim();

src/test/kotlin/sirius/kernel/commons/StringsTest.kt

@@ -303,12 +303,20 @@ class StringsTest {
     fun limit() {
         assertEquals("", Strings.limit(null, 10, false))
         assertEquals("", Strings.limit(null, 10, true))
+        assertEquals("", Strings.limit(null, -10, true))
         assertEquals("", Strings.limit("", 10, false))
         assertEquals("", Strings.limit("", 10, true))
+        assertEquals("", Strings.limit("", -10, true))
         assertEquals("ABCDE", Strings.limit("ABCDE", 10, false))
         assertEquals("ABCDE", Strings.limit("ABCDE", 10, true))
+        assertEquals("", Strings.limit("ABCDE", -10, true))
         assertEquals("ABCDEFGHIJ", Strings.limit("ABCDEFGHIJKLMNOP", 10, false))
         assertEquals("ABCDEFGHI…", Strings.limit("ABCDEFGHIJKLMNOP", 10, true))
+        assertEquals("", Strings.limit("ABCDEFGHIJKLMNOP", -10, true))
+        assertEquals("", Strings.limit("A", 0, true))
+        assertEquals("", Strings.limit("A", 0, false))
+        assertEquals("A", Strings.limit("A", 1, true))
+        assertEquals("A", Strings.limit("A", 1, false))
     }
 
 }