[Dev] Chandler date/time related changes

[Andi Vajda]

These changes, as described in an earlier message, have been checked in.
After your next 'cvs update' you need to first run 'make install' and then 
re-create your repository as some core schema types have changed.

Andi..

On Tue, 24 May 2005, Andi Vajda wrote:

>
> In the past two weeks I implemented a bunch of changes related to dates, 
> times and calendars in order to make localizing Chandler easier:
>
>  - started a new project, called PyICU, which is a set of python extensions
>    wrapping IBM's ICU C++ APIs with SWIG. Currently PyICU wraps the ICU base
>    classes such as UnicodeString, Locale, TimeZone, the format classes and
>    the calendar classes. More wrapping is in the works.
>    For more information about PyICU, see its subversion repository at
>        http://svn.osafoundation.org/pyicu/trunk
>    and its README file.
>
>  - added ICU and PyICU to Chandler's build.
>
>  - changed the underlying implementation of the repository core schema types
>    DateTime and DateTimeDelta to no longer use mxDateTime but the python
>    builtin types provided by the datetime module.
>    The new set of date and time types in the repository core schema is:
>      - DateTime: implemented by a python datetime, this type now supports
>        timezones as specified by ICU using the new ICUtzinfo helper class as
>        implemented by PyICU. For example:
>          now = datetime.now(tz=ICUtzinfo.getInstance('Pacific/Honolulu'))
>          (ICU supports 577 such timezone names)
>      - Time: implemented by a python time, supports timezones too. This is
>        a new type in the repository core schema.
>      - Date: implemented by a python date. This is a new type in the
>        repository core schema.
>      - TimeDelta: implemented by a python timedelta. This type replaces the
>        the former DateTimeDelta type.
>    Also, I removed RelativeDateTime as it seemed redundant. All uses of it
>    could be replaced by a TimeDelta value instead, except for one case where
>    I used the ICU Calendar class for assistance. If it turns out that we
>    actually need a RelativeDateTime type as was implemented by mxDateTime,
>    the python dateutil module has a very reasonable implementation that we
>    could add later.
>    As a result of all of these changes, we should be able to remove the
>    egenix system from our build in the near future.
>
>  - changed all Chandler code using the old mx types to use the python
>    builtins instead. This involved changing lots of code all over, the diffs
>    are attached to this message for your review. Chandler appears to run
>    fine, all unit tests pass but I sure could have broken stuff along the
>    way, especially in the UI.
>
>  - to illustrate the benefits of all this, I also enhanced the Calendar UI
>    somewhat to be less hardcoded and use the ICU library for getting month
>    and day names and other info such as first-day-of-week. I also added a 
> new
>    command line flag to starting Chandler, --locale, which accepts a 
> standard
>    locale name and that sets ICU's default locale to it. The calendar UI is
>    displayed in the chosen locale. For example, use:
>      ../release/RunChandler --locale pt_BR
>    to display the calendar in Brazilian Portuguese. On my Mac, I can even
>    run it in Chinese:
>      ../release/RunChandler --locale zh_TW
>
>  I'd like to check all of this in *before* the scheduled cvs/svn conversion,
>  that is tonight, but more testing is still needed.
>
>  In the meantime, comments are welcome !
>
> Andi..