This is a meta-issue to collect all the things we want to have in v0.8 (see also the milestone) and how we want to get there. I'll try to keep this list updated when things change over time.

Update 11.07.2022 with things sorted according to what will be included in a v0.8 alpha release, what we hopefully manage to do before an actual release (or maybe just let the users do all the testing?), and what will be deferred for the next version.

Major Changes included in / missing for v0.8 alpha

• remove arrow, transition to attrs and add Timespan (PR Remove arrow, transition to attrs and add Timespan #222, including the old ToDo list)
• migration to new data conversion implementation (PR [WIP] new implementation of parsing and serialization #240, PR improved ComponentMeta system and Timezone conversion #249)
• new build system (PR New build system #243, Move build system from poetry to hatch #354)
• proper timezone handling (PR improved ComponentMeta system and Timezone conversion #249, Add VTIMEZONE / tzinfo Serialization and better TZID Parsing #129, Time zone conversion support #161)
• faster ContentLine parser implementation (PR Contentline parser #247, V0.7 is much slower to parse large calendar feed then V0.5 #244)
• line folding (ics does not support 5545 3.1 (long line folding) #215, Long DESCRIPTION has embedded newline #210)
• parsing / serialization hooks and customizations (PRs improved ComponentMeta system and Timezone conversion #249, [WIP] Converter System clean-up #355)
• auto-formatting, more automatic checks and fixes, also including the documentation (PR Introduce auto-formatters #351, Docstring formatting #344)
• the ics_vtimezones project should have a new release in sync with our 0.8 release

Missing Tests and Open ToDos for v0.8 release

• improved documentation (Improve the documentation of ics #220, Improve docstrings in classes & functions for API #225, PR Restructure documentation #223)
• finally working all_day event support (make_all_day() issues #155, all-day event is still off by one day #173, Off by one issues in all-day events #92, ...)
• real world test data ([POC] Create a corpus of various ics files for more robust tests #236)
• migration of old test suite
• full test coverage for new code
• tests preventing regressions on old bugs (PR improved ComponentMeta system and Timezone conversion #249)
  Timezone information of time fields is ignored #181, Timestamp seconds are ignored #182, Timezone information is dropped when converting internally to UTC #188, ...
• test compatibility with other tools (Outlook, Apple Calendar, Google, Thunderbird, Evolution)
  esp. with regard to line-folding, attribute preservation and interpretation

Wishlist for v0.9

• recurring events (Support recuring events #14, Add priority, due date and rrule to Event class  #168)
• varying levels of strictness (validate vs. try hard to interpolate the right data)
• webcal, jcal, vcards
• parity with all RFC 5545 / 7986 properties (Support of SEQUENCE property #115, Consider adding fields from RFC-7986 #307)
• "compatibility" serialization for different targets / RFC versions (i.e. Google, Outlook, RFC5545 vs RFC7986, X-WR-CALNAME vs NAME)