From fd6df00753a6c964225e7c6b505ab125cb412b90 Mon Sep 17 00:00:00 2001
From: NikEasY <tkachiv10@gmail.com>
Date: Fri, 26 May 2023 15:49:39 +0300
Subject: [PATCH 1/2] refactored DURATION_REGEX

---
 src/icalendar/prop.py | 39 +++++++++++++++++++--------------------
 1 file changed, 19 insertions(+), 20 deletions(-)

diff --git a/src/icalendar/prop.py b/src/icalendar/prop.py
index ac87d0ba..7ee13468 100644
--- a/src/icalendar/prop.py
+++ b/src/icalendar/prop.py
@@ -63,12 +63,9 @@
 import time as _time
 
 
-DATE_PART = r'(\d+)D'
-TIME_PART = r'T(?:(\d+)H)?(?:(\d+)M)?(?:(\d+)S)?'
-DATETIME_PART = f'(?:{DATE_PART})?(?:{TIME_PART})?'
-WEEKS_PART = r'(\d+)W'
-DURATION_REGEX = re.compile(r'([-+]?)P(?:%s|%s)$'
-                            % (WEEKS_PART, DATETIME_PART))
+DURATION_REGEX = re.compile(r'([-+]?)P(?:(\d+)W)?(?:(\d+)D)?'
+                            r'(?:T(?:(\d+)H)?(?:(\d+)M)?(?:(\d+)S)?)?$')
+
 WEEKDAY_RULE = re.compile(r'(?P<signal>[+-]?)(?P<relative>[\d]?)'
                           r'(?P<weekday>[\w]{2})$')
 
@@ -475,22 +472,24 @@ def to_ical(self):
 
     @staticmethod
     def from_ical(ical):
-        try:
-            match = DURATION_REGEX.match(ical)
-            sign, weeks, days, hours, minutes, seconds = match.groups()
-            if weeks:
-                value = timedelta(weeks=int(weeks))
-            else:
-                value = timedelta(days=int(days or 0),
-                                  hours=int(hours or 0),
-                                  minutes=int(minutes or 0),
-                                  seconds=int(seconds or 0))
-            if sign == '-':
-                value = -value
-            return value
-        except Exception:
+        match = DURATION_REGEX.match(ical)
+        if not match:
             raise ValueError(f'Invalid iCalendar duration: {ical}')
 
+        sign, weeks, days, hours, minutes, seconds = match.groups()
+        value = timedelta(
+            weeks=int(weeks or 0),
+            days=int(days or 0),
+            hours=int(hours or 0),
+            minutes=int(minutes or 0),
+            seconds=int(seconds or 0)
+        )
+
+        if sign == '-':
+            value = -value
+
+        return value
+
 
 class vPeriod:
     """A precise period of time.

From 45aaeaa305ab444e947b2b2601d9daedd48dd1e8 Mon Sep 17 00:00:00 2001
From: NikEasY <tkachiv10@gmail.com>
Date: Fri, 26 May 2023 21:24:45 +0300
Subject: [PATCH 2/2] added changelog

---
 CHANGES.rst      | 2 +-
 docs/credits.rst | 1 +
 2 files changed, 2 insertions(+), 1 deletion(-)

diff --git a/CHANGES.rst b/CHANGES.rst
index bac3d1a5..5e64c10d 100644
--- a/CHANGES.rst
+++ b/CHANGES.rst
@@ -6,7 +6,7 @@ Changelog
 
 Minor changes:
 
-- ...
+- Adjusted duration regex
 
 Breaking changes:
 
diff --git a/docs/credits.rst b/docs/credits.rst
index 0623611d..1cf1df80 100644
--- a/docs/credits.rst
+++ b/docs/credits.rst
@@ -67,6 +67,7 @@ icalendar contributors
 - Pronoy <lukex9442@gmail.com>
 - Abe Hanoka <abe@habet.dev>
 - `Natasha Mattson <https://github.com/natashamm`_
+- `NikEasY <https://github.com/NikEasY>`_
 
 Find out who contributed::