Issue 1 add vtimezone

README.md

@@ -67,9 +67,8 @@ You can use MergeCal in your Python code as follows:
 >>> merged_calendar : Calendar = merge_calendars([calendar1, calendar2])
 
 # Write the merged calendar to a file
->>> with (CALENDARS / "merged_calendar.ics").open("wb") as f:
-...     f.write(merged_calendar.to_ical())
-559
+>>> (CALENDARS / "merged_calendar.ics").write_bytes(merged_calendar.to_ical())
+933
 
 # The merged calendar will contain all the events of both calendars
 >>> [str(event["SUMMARY"]) for event in calendar1.walk("VEVENT")]

pyproject.toml

@@ -29,6 +29,7 @@ dependencies = [
   "icalendar>=6.1.1",
   "rich>=10",
   "typer>=0.15,<1",
+  "x-wr-timezone>=2.0.1"
 ]
 urls."Bug Tracker" = "https://github.com/abe-101/mergecal/issues"
 urls.Changelog = "https://github.com/abe-101/mergecal/blob/main/CHANGELOG.md"

src/mergecal/calendar_merger.py

@@ -1,6 +1,7 @@
 from typing import Optional
 
-from icalendar import Calendar
+from icalendar import Calendar, Event
+from x_wr_timezone import to_standard
 
 
 def generate_default_prodid() -> str:
@@ -18,9 +19,6 @@ def __init__(
         version: str = "2.0",
         method: Optional[str] = None,
     ):
-        if not calendars:
-            raise ValueError("At least one calendar must be provided")
-
         self.merged_calendar = Calendar()
 
         # Set required properties
@@ -31,29 +29,42 @@ def __init__(
         if method:
             self.merged_calendar.add("method", method)
 
-        self.calendars: list[Calendar] = calendars
+        self.calendars: list[Calendar] = []
+
+        for calendar in calendars:
+            self.add_calendar(calendar)
 
     def add_calendar(self, calendar: Calendar) -> None:
         """Add a calendar to be merged."""
-        self.calendars.append(calendar)
+        self.calendars.append(to_standard(calendar, add_timezone_component=True))
 
     def merge(self) -> Calendar:
         """Merge the calendars."""
-        existing_uids = set()
+        existing_uids: set[tuple[Optional[str], int, Optional[str]]] = set()
+        no_uid_events: list[Event] = []
+        tzids: set[str] = set()
         for cal in self.calendars:
-            for component in cal.events:
-                uid = component.get("uid", None)
-                sequence = component.get("sequence", 0)
-                recurrence_id = component.get("recurrence-id", None)
+            for timezone in cal.timezones:
+                if timezone.tz_name not in tzids:
+                    self.merged_calendar.add_component(timezone)
+                    tzids.add(timezone.tz_name)
+            for event in cal.events:
+                uid = event.get("uid", None)
+                sequence = event.get("sequence", 0)
+                recurrence_id = event.get("recurrence-id", None)
 
                 # Create a unique identifier for the component
                 component_id = (uid, sequence, recurrence_id)
 
-                if uid is not None and component_id in existing_uids:
+                if uid is None:
+                    if event in no_uid_events:
+                        continue
+                    no_uid_events.append(event)
+                elif component_id in existing_uids:
                     continue
 
                 existing_uids.add(component_id)
-                self.merged_calendar.add_component(component)
+                self.merged_calendar.add_component(event)
 
         return self.merged_calendar
 

tests/calendars/x_wr_timezone.ics

@@ -0,0 +1,36 @@
+BEGIN:VCALENDAR
+PRODID:-//Google Inc//Google Calendar 70.9054//EN
+VERSION:2.0
+CALSCALE:GREGORIAN
+METHOD:PUBLISH
+X-WR-CALNAME:This calendar features two events of which DTSTART and DTEND must be changed.
+X-WR-TIMEZONE:America/New_York
+BEGIN:VEVENT
+DTSTART:20211222T170000Z
+DTEND:20211222T180000Z
+DTSTAMP:20211228T180046Z
+UID:3bc4jff97631or97ntnk75n4se@google.com
+CREATED:20211222T190737Z
+DESCRIPTION:
+LAST-MODIFIED:20211222T190947Z
+LOCATION:
+SEQUENCE:2
+STATUS:CONFIRMED
+SUMMARY:Google Calendar says this is noon to 1PM on 12/22/2021
+TRANSP:OPAQUE
+END:VEVENT
+BEGIN:VEVENT
+DTSTART:20211223T020000Z
+DTEND:20211223T030000Z
+DTSTAMP:20211228T180046Z
+UID:14n7h56i35m32ukcq76s46d45p@google.com
+CREATED:20211222T190622Z
+DESCRIPTION:
+LAST-MODIFIED:20211222T190622Z
+LOCATION:
+SEQUENCE:0
+STATUS:CONFIRMED
+SUMMARY:Google says this is 9PM to 10PM on 12/22/2021
+TRANSP:OPAQUE
+END:VEVENT
+END:VCALENDAR

tests/conftest.py

@@ -17,6 +17,9 @@ def merge_func(calendars: list[str]) -> icalendar.Calendar:
     """Use the main merge function to merge the calendars."""
     icalendars = []
     for calendar in calendars:
+        if isinstance(calendar, icalendar.Calendar):
+            icalendars.append(calendar)
+            continue
         if not calendar.endswith(".ics"):
             calendar += ".ics"
         calendar_path = CALENDARS_DIR / calendar
@@ -48,12 +51,17 @@ class ICSCalendars:
 
     def get_calendar(self, content):
         """Return the calendar given the content."""
-        return icalendar.Calendar(content)
+        return icalendar.Calendar.from_ical(content)
 
     def __getitem__(self, name):
         """Return the calendar from the calendars directory."""
         return getattr(self, name)
 
+    @staticmethod
+    def keys() -> list[str]:
+        """The names of all calendars."""
+        return [calendar_path.stem for calendar_path in CALENDARS_DIR.iterdir()]
+
 
 for calendar_path in CALENDARS_DIR.iterdir():
     content = calendar_path.read_bytes()
@@ -72,6 +80,12 @@ def calendars() -> ICSCalendars:
     return ICSCalendars()
 
 
+@pytest.fixture(params=ICSCalendars.keys())
+def a_calendar(request):
+    """Return a calendar."""
+    return request.param
+
+
 def doctest_print(obj):
     """Doctest print."""
     if isinstance(obj, bytes):

tests/test_issue_1_include_timezones.py

@@ -0,0 +1,29 @@
+"""The timezones are a valuable part of the calendar and must be included."""
+
+from icalendar import Calendar
+
+
+def test_merged_calendars_include_a_timezone(merge, calendars):
+    """The timezones should be included."""
+    calendar: Calendar = merge([calendars.one_event])
+    assert len(calendar.timezones) == 1
+    assert calendar.timezones[0].tz_name == "Europe/Berlin"
+
+
+def test_merge_with_no_calendars(merge):
+    """No calendars no timezone."""
+    calendar: Calendar = merge([])
+    assert len(calendar.timezones) == 0
+
+
+def test_empty_calendar_has_no_timezone(merge):
+    """Empty calendar merged ahs no timezone."""
+    calendar: Calendar = merge([Calendar()])
+    assert len(calendar.timezones) == 0
+
+
+def test_x_wr_timezone_is_included(merge, calendars):
+    """The x-wr-timezone property should create a timezone."""
+    calendar: Calendar = merge([calendars.x_wr_timezone])
+    assert calendar.timezones[0].tz_name == "America/New_York"
+    assert calendar.events[1].start.tzname() == "EST"

tests/test_merge_calendars.py

@@ -37,3 +37,17 @@ def test_merge_calendars_with_recurring_events(merge):
     assert modified_event.get("sequence", 0) > recurring_event.get("sequence", 0), (
         "Modified event should have a higher sequence number"
     )
+
+
+def test_merging_a_calendar_with_itself_returns_the_same_calendar(merge, a_calendar):
+    """The calendar should not be duplicated."""
+    cal_1 = merge([a_calendar])
+    cal_2 = merge([a_calendar, a_calendar])
+    assert cal_1 == cal_2
+
+
+def test_merging_is_reproducible(merge, a_calendar):
+    """We expect the same result when merging a calendar."""
+    cal_1 = merge([a_calendar])
+    cal_2 = merge([a_calendar])
+    assert cal_1 == cal_2

tests/test_with_doctest.py

@@ -47,4 +47,4 @@ def test_documentation_file(document, env_for_doctest):
         globs=env_for_doctest,
         raise_on_error=False,
     )
-    assert test_result.failed == 0, f"{test_result.failed} errors in {document.name}"
+    assert test_result.failed == 0, f"{test_result.failed} errors in {document}"