feat: merge RFC 7986 COLOR property for calendar components

Author: SashankBhamidi

.github/workflows/ci.yml

@@ -36,7 +36,6 @@ jobs:
       fail-fast: false
       matrix:
         python-version:
-          - "3.9"
           - "3.10"
           - "3.11"
           - "3.12"

README.md

@@ -75,7 +75,7 @@ You can use MergeCal in your Python code as follows:
 
 # Write the merged calendar to a file
 >>> (CALENDARS / "merged_calendar.ics").write_bytes(merged_calendar.to_ical())
-953
+998
 
 # The merged calendar will contain all the events of both calendars
 >>> [str(event["SUMMARY"]) for event in calendar1.walk("VEVENT")]

pyproject.toml

@@ -11,13 +11,12 @@ license = { text = "GNU General Public License v3" }
 authors = [
   { name = "Abe Hanoka", email = "abe@habet.dev" },
 ]
-requires-python = ">=3.9"
+requires-python = ">=3.10"
 classifiers = [
   "Development Status :: 2 - Pre-Alpha",
   "Intended Audience :: Developers",
   "Natural Language :: English",
   "Operating System :: OS Independent",
-  "Programming Language :: Python :: 3.9",
   "Programming Language :: Python :: 3.10",
   "Programming Language :: Python :: 3.11",
   "Programming Language :: Python :: 3.12",
@@ -26,7 +25,7 @@ classifiers = [
 ]
 
 dependencies = [
-  "icalendar>=6.1.1",
+  "icalendar>=7.0.0",
   "rich>=10",
   "typer>=0.15,<1",
   "x-wr-timezone>=2.0.1"
@@ -50,7 +49,7 @@ docs = [
 ]
 
 [tool.ruff]
-target-version = "py39"
+target-version = "py310"
 line-length = 88
 lint.select = [
   "B",   # flake8-bugbear

src/mergecal/calendar_merger.py

@@ -1,6 +1,4 @@
-from typing import Optional
-
-from icalendar import Calendar, Event
+from icalendar import Calendar, Event, Journal, Todo
 from x_wr_timezone import to_standard
 
 
@@ -20,19 +18,17 @@ class CalendarMerger:
     def __init__(
         self,
         calendars: list[Calendar],
-        prodid: Optional[str] = None,
+        prodid: str | None = None,
         version: str = "2.0",
         calscale: str = "GREGORIAN",
-        method: Optional[str] = None,
+        method: str | None = None,
     ):
         self.merged_calendar = Calendar()
 
-        # Set required properties
         self.merged_calendar.add("prodid", prodid or generate_default_prodid())
         self.merged_calendar.add("version", version)
         self.merged_calendar.add("calscale", calscale)
 
-        # Set optional properties if provided
         if method:
             self.merged_calendar.add("method", method)
 
@@ -47,32 +43,78 @@ def add_calendar(self, calendar: Calendar) -> None:
 
     def merge(self) -> Calendar:
         """Merge the calendars."""
-        existing_uids: set[tuple[Optional[str], int, Optional[str]]] = set()
+        seen_events: set[tuple[str | None, int, str | None]] = set()
+        seen_todos: set[tuple[str | None, int, str | None]] = set()
+        seen_journals: set[str] = set()
         no_uid_events: list[Event] = []
+        no_uid_todos: list[Todo] = []
+        no_uid_journals: list[Journal] = []
         tzids: set[str] = set()
         for cal in self.calendars:
+            # .color resolves COLOR then X-APPLE-CALENDAR-COLOR (RFC 7986 §5.9)
+            cal_color = cal.color
+
+            if cal_color and not self.merged_calendar.color:
+                self.merged_calendar.color = cal_color
+
             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 None:
                     if event in no_uid_events:
                         continue
                     no_uid_events.append(event)
-                elif component_id in existing_uids:
+                elif component_id in seen_events:
                     continue
 
-                existing_uids.add(component_id)
+                if cal_color and not event.color:
+                    event.color = cal_color
+
+                seen_events.add(component_id)
                 self.merged_calendar.add_component(event)
 
+            for todo in cal.todos:
+                uid = todo.get("uid", None)
+                recurrence_id = todo.get("recurrence-id", None)
+                component_id = (uid, todo.get("sequence", 0), recurrence_id)
+
+                if uid is None:
+                    if todo in no_uid_todos:
+                        continue
+                    no_uid_todos.append(todo)
+                elif component_id in seen_todos:
+                    continue
+
+                if cal_color and not todo.color:
+                    todo.color = cal_color
+
+                seen_todos.add(component_id)
+                self.merged_calendar.add_component(todo)
+
+            for journal in cal.walk("VJOURNAL"):
+                uid = journal.get("uid", None)
+
+                if uid is None:
+                    if journal in no_uid_journals:
+                        continue
+                    no_uid_journals.append(journal)
+                elif uid in seen_journals:
+                    continue
+
+                if cal_color and not journal.color:
+                    journal.color = cal_color
+
+                seen_journals.add(uid)
+                self.merged_calendar.add_component(journal)
+
         return self.merged_calendar
 
 

src/mergecal/cli.py

@@ -1,5 +1,4 @@
 from pathlib import Path
-from typing import Optional
 
 import typer
 from rich import print
@@ -21,8 +20,8 @@
 def main(
     calendars: list[Path] = calendars_arg,
     output: Path = output_opt,
-    prodid: Optional[str] = prodid_opt,
-    method: Optional[str] = method_opt,
+    prodid: str | None = prodid_opt,
+    method: str | None = method_opt,
 ) -> None:
     """Merge multiple iCalendar files into one."""
     try:

tests/calendars/color_apple.ics

@@ -0,0 +1,13 @@
+BEGIN:VCALENDAR
+VERSION:2.0
+PRODID:-//Test//Test//EN
+CALSCALE:GREGORIAN
+X-APPLE-CALENDAR-COLOR:#e78074
+BEGIN:VEVENT
+UID:color-apple-event-1@test
+SUMMARY:Event with Apple calendar color
+DTSTART:20190304T080000Z
+DTEND:20190304T083000Z
+DTSTAMP:20190303T111937Z
+END:VEVENT
+END:VCALENDAR

tests/calendars/color_event_own.ics

@@ -0,0 +1,26 @@
+BEGIN:VCALENDAR
+VERSION:2.0
+PRODID:-//Test//Test//EN
+CALSCALE:GREGORIAN
+COLOR:plum
+BEGIN:VEVENT
+UID:color-event-own-1@test
+SUMMARY:Event with its own color
+DTSTART:20190304T080000Z
+DTEND:20190304T083000Z
+DTSTAMP:20190303T111937Z
+COLOR:navy
+END:VEVENT
+BEGIN:VTODO
+UID:color-todo-own-1@test
+SUMMARY:Todo with its own color
+DTSTAMP:20190303T111937Z
+COLOR:navy
+END:VTODO
+BEGIN:VJOURNAL
+UID:color-journal-own-1@test
+SUMMARY:Journal with its own color
+DTSTAMP:20190303T111937Z
+COLOR:navy
+END:VJOURNAL
+END:VCALENDAR

tests/calendars/color_none.ics

@@ -0,0 +1,12 @@
+BEGIN:VCALENDAR
+VERSION:2.0
+PRODID:-//Test//Test//EN
+CALSCALE:GREGORIAN
+BEGIN:VEVENT
+UID:color-none-event-1@test
+SUMMARY:Event with no calendar color
+DTSTART:20190304T080000Z
+DTEND:20190304T083000Z
+DTSTAMP:20190303T111937Z
+END:VEVENT
+END:VCALENDAR

tests/calendars/color_rfc7986.ics

@@ -0,0 +1,23 @@
+BEGIN:VCALENDAR
+VERSION:2.0
+PRODID:-//Test//Test//EN
+CALSCALE:GREGORIAN
+COLOR:turquoise
+BEGIN:VEVENT
+UID:color-rfc7986-event-1@test
+SUMMARY:Event with RFC 7986 calendar color
+DTSTART:20190304T080000Z
+DTEND:20190304T083000Z
+DTSTAMP:20190303T111937Z
+END:VEVENT
+BEGIN:VTODO
+UID:color-rfc7986-todo-1@test
+SUMMARY:Todo with RFC 7986 calendar color
+DTSTAMP:20190303T111937Z
+END:VTODO
+BEGIN:VJOURNAL
+UID:color-rfc7986-journal-1@test
+SUMMARY:Journal with RFC 7986 calendar color
+DTSTAMP:20190303T111937Z
+END:VJOURNAL
+END:VCALENDAR

tests/test_color_merging.py

@@ -0,0 +1,40 @@
+"""Tests for RFC 7986 COLOR property merging."""
+
+import pytest
+
+from mergecal import merge_calendars
+
+
+@pytest.mark.parametrize("component_type", ["VEVENT", "VTODO", "VJOURNAL"])
+def test_component_inherits_calendar_color(calendars, component_type):
+    result = merge_calendars(calendars.color_rfc7986.stream)  # type: ignore[attr-defined]
+    assert result.walk(component_type)[0].color == "turquoise"
+
+
+def test_event_inherits_apple_calendar_color(calendars):
+    result = merge_calendars(calendars.color_apple.stream)  # type: ignore[attr-defined]
+    assert result.events[0].color == "#e78074"
+
+
+@pytest.mark.parametrize("component_type", ["VEVENT", "VTODO", "VJOURNAL"])
+def test_component_own_color_not_overwritten(calendars, component_type):
+    result = merge_calendars(calendars.color_event_own.stream)  # type: ignore[attr-defined]
+    assert result.walk(component_type)[0].color == "navy"
+
+
+def test_no_color_when_calendar_has_none(calendars):
+    result = merge_calendars(calendars.color_none.stream)  # type: ignore[attr-defined]
+    assert not result.color
+    assert not result.events[0].color
+
+
+def test_merged_calendar_color_first_wins(calendars):
+    cals = calendars.color_rfc7986.stream + calendars.color_apple.stream  # type: ignore[attr-defined]
+    result = merge_calendars(cals)
+    assert result.color == "turquoise"
+
+
+def test_merged_calendar_color_when_only_one_has_color(calendars):
+    cals = calendars.color_none.stream + calendars.color_rfc7986.stream  # type: ignore[attr-defined]
+    result = merge_calendars(cals)
+    assert result.color == "turquoise"