diff --git a/src/main/php/util/TimeSpan.class.php b/src/main/php/util/TimeSpan.class.php
index 98b1fe72b..0ba514666 100755
--- a/src/main/php/util/TimeSpan.class.php
+++ b/src/main/php/util/TimeSpan.class.php
@@ -1,27 +1,48 @@
 <?php namespace util;
 
+use DateInterval, Exception;
 use lang\{Value, IllegalArgumentException, IllegalStateException};
 
 /**
  * Represents a span of time
  *
- * @see   util.Dates::diff()
- * @test  net.xp_framework.unittest.util.TimeSpanTest
+ * @see  util.Dates::diff()
+ * @test net.xp_framework.unittest.util.TimeSpanTest
  */
 class TimeSpan implements Value {
-  protected $_seconds = 0;
+  protected $_seconds;
   
   /**
-   * Contructor
+   * Constructor
    *
-   * @param   int secs - an amount of seconds, absolute value is used
-   * @throws  lang.IllegalArgumentException in case the value given is not numeric
+   * @param  int|string|DateInterval $arg
+   * @throws lang.IllegalArgumentException
    */
-  public function __construct($secs= 0) {
-    if (!is_numeric($secs)) {
-      throw new IllegalArgumentException('Given argument is not an integer: '.typeof($secs)->getName());
+  public function __construct($arg) {
+    if (is_numeric($arg)) {
+      $this->_seconds= (int)abs($arg);
+    } else {
+      try {
+        if ($arg instanceof DateInterval) {
+          $i= $arg;
+        } else if ('P' === $arg[0] ?? null) {
+          $i= new DateInterval($arg);
+        } else {
+          $i= DateInterval::createFromDateString($arg);
+        }
+      } catch (Exception $e) {
+        throw new IllegalArgumentException('Invalid time span '.Objects::stringOf($arg), $e);
+      }
+
+      // PHP < 8.3 returns false for invalid time spans
+      if (false === $i) throw new IllegalArgumentException('Invalid time span '.Objects::stringOf($arg));
+
+      // Years and months do not have a constant amount of seconds. Technically, days
+      // don't either (think: leap seconds), but we'll handle them as 86400 seconds
+      if ($i->y || $i->m) throw new IllegalArgumentException('Cannot create from interval with years / months');
+
+      $this->_seconds= $i->d * 86400 + $i->h * 3600 + $i->i * 60 + $i->s;
     }
-    $this->_seconds= (int)abs($secs);
   }
 
   /**
diff --git a/src/test/php/util/unittest/TimeSpanTest.class.php b/src/test/php/util/unittest/TimeSpanTest.class.php
index ae8212ba5..828fff923 100755
--- a/src/test/php/util/unittest/TimeSpanTest.class.php
+++ b/src/test/php/util/unittest/TimeSpanTest.class.php
@@ -1,24 +1,35 @@
 <?php namespace util\unittest;
 
+use DateInterval;
 use lang\{IllegalArgumentException, IllegalStateException};
-use test\{Assert, Expect, Test};
+use test\{Assert, Expect, Test, Values};
 use util\TimeSpan;
 
 class TimeSpanTest {
   
-  #[Test]
-  public function newTimeSpan() {
-    Assert::equals('0d, 2h, 1m, 5s', (new TimeSpan(7265))->toString());
+  #[Test, Values([7265, 7265.0, 'PT2H1M5S', '2 hours 1 minute 5 seconds'])]
+  public function span_from($arg) {
+    Assert::equals('0d, 2h, 1m, 5s', (new TimeSpan($arg))->toString());
   }
 
   #[Test]
-  public function newNegativeTimeSpan() {
+  public function negative_span() {
     Assert::equals('0d, 0h, 0m, 1s', (new TimeSpan(-1))->toString());
   }
 
-  #[Test, Expect(IllegalArgumentException::class)]
-  public function wrongArguments() {
-    new TimeSpan('2 days');
+  #[Test, Expect(IllegalArgumentException::class), Values([null, '', 'not a time span', false, true])]
+  public function invalid_string_argument($arg) {
+    new TimeSpan($arg);
+  }
+
+  #[Test, Expect(IllegalArgumentException::class), Values(['P1Y', 'P1M'])]
+  public function unsupported_dateinterval($arg) {
+    new TimeSpan(new DateInterval($arg));
+  }
+
+  #[Test]
+  public function span_from_dateinterval() {
+    Assert::equals('1d, 2h, 0m, 0s', (new TimeSpan(new DateInterval('P1DT2H')))->toString());
   }
 
   #[Test]
@@ -33,12 +44,13 @@ public function add() {
   public function subtract() {
     Assert::equals('0d, 22h, 58m, 55s', (new TimeSpan(86400))
       ->substract(new TimeSpan(3600), new TimeSpan(60))
-      ->substract(new TimeSpan(5))->toString()
+      ->substract(new TimeSpan(5))
+      ->toString()
     );
   }
 
   #[Test]
-  public function subtractToZero() {
+  public function subtract_resulting_in_zero() {
     Assert::equals(
       '0d, 0h, 0m, 0s', 
       (new TimeSpan(6100))->substract(new TimeSpan(6100))->toString()
@@ -46,50 +58,51 @@ public function subtractToZero() {
   }
 
   #[Test, Expect(IllegalStateException::class)]
-  public function subtractToNegative() {
+  public function subtract_may_not_result_in_negative_values() {
     (new TimeSpan(0))->substract(new TimeSpan(1));
   }
 
   #[Test]
-  public function addAndSubstract() {
+  public function add_and_subtract() {
     Assert::equals('1d, 1h, 0m, 55s', (new TimeSpan(86400))
       ->add(new TimeSpan(3600), new TimeSpan(60))
-      ->substract(new TimeSpan(5))->toString()
+      ->substract(new TimeSpan(5))
+      ->toString()
     );
   }
 
   #[Test, Expect(IllegalArgumentException::class)]
-  public function addWrongArguments() {
+  public function incorrect_argument_to_add() {
     (new TimeSpan(0))->add('2 days');
   }
 
   #[Test]
-  public function fromSeconds() {
+  public function from_seconds() {
     Assert::equals('0d, 1h, 0m, 0s', TimeSpan::seconds(3600)->toString());
   }
 
   #[Test]
-  public function fromMinutes() {
+  public function from_minutes() {
     Assert::equals('0d, 2h, 7m, 0s', TimeSpan::minutes(127)->toString());
   }
   
   #[Test]
-  public function fromHours() {
+  public function from_hours() {
     Assert::equals('1d, 3h, 0m, 0s', TimeSpan::hours(27)->toString());
   }
 
   #[Test]
-  public function fromDays() {
+  public function from_days() {
     Assert::equals('40d, 0h, 0m, 0s', TimeSpan::days(40)->toString());
   }
   
   #[Test]
-  public function fromWeeks() {
+  public function from_weeks() {
     Assert::equals('7d, 0h, 0m, 0s', TimeSpan::weeks(1)->toString());
   }
 
   #[Test]
-  public function wholeValues() {
+  public function whole_values() {
     $t= new TimeSpan(91865);
     Assert::equals(5, $t->getWholeSeconds(), 'wholeSeconds');
     Assert::equals(31, $t->getWholeMinutes(), 'wholeMinutes');
@@ -98,77 +111,77 @@ public function wholeValues() {
   }
 
   #[Test]
-  public function formatSeconds() {
+  public function format_seconds() {
     Assert::equals('91865', (new TimeSpan(91865))->format('%s'));
   }
 
   #[Test]
-  public function formatWholeSeconds() {
+  public function format_whole_seconds() {
     Assert::equals('5', (new TimeSpan(91865))->format('%w'));
   }
 
   #[Test]
-  public function formatMinutes() {
+  public function format_minutes() {
     Assert::equals('1531', (new TimeSpan(91865))->format('%m'));
   }
 
   #[Test]
-  public function formatFloatMinutes() {
+  public function format_float_minutes() {
     Assert::equals('1531.08', (new TimeSpan(91865))->format('%M'));
   }
 
   #[Test]
-  public function formatWholeMinutes() {
+  public function format_whole_minutes() {
     Assert::equals('31', (new TimeSpan(91865))->format('%j'));
   }
 
   #[Test]
-  public function formatHours() {
+  public function format_hours() {
     Assert::equals('25', (new TimeSpan(91865))->format('%h'));
   }
 
   #[Test]
-  public function formatFloatHours() {
+  public function format_float_hours() {
     Assert::equals('25.52', (new TimeSpan(91865))->format('%H'));
   }
 
   #[Test]
-  public function formatWholeHours() {
+  public function format_whole_hours() {
     Assert::equals('1', (new TimeSpan(91865))->format('%y'));
   }
 
   #[Test]
-  public function formatDays() {
+  public function format_days() {
     Assert::equals('1', (new TimeSpan(91865))->format('%d'));
   }
 
   #[Test]
-  public function formatFloatDays() {
+  public function format_float_days() {
     Assert::equals('1.06', (new TimeSpan(91865))->format('%D'));
   }
 
   #[Test]
-  public function formatWholeDays() {
+  public function format_whole_days() {
     Assert::equals('1', (new TimeSpan(91865))->format('%e'));
   }
 
   #[Test]
-  public function format() {
+  public function format_() {
     Assert::equals('1d1h', (new TimeSpan(91865))->format('%ed%yh'));
   }
 
   #[Test]
-  public function formatPercent() {
+  public function format_percent() {
     Assert::equals('%1d%1h%', (new TimeSpan(91865))->format('%%%ed%%%yh%%'));
   }
 
   #[Test]
-  public function compareTwoEqualInstances() {
+  public function compare_two_equal_instances() {
     Assert::equals(new TimeSpan(3600), new TimeSpan(3600));
   }
 
   #[Test]
-  public function compareTwoUnequalInstances() {
+  public function compare_two_differing_instances() {
     Assert::notEquals(new TimeSpan(3600), new TimeSpan(0));
   }
 }
\ No newline at end of file