Changelog

CRAN MAINTENANCE

A test that was failing due to an incorrect assumption that the first day of the year would always fall on the first week of the year was fixed (see https://github.com/reconhub/aweek/issues/35 for details). (#36, @zkamvar).

Continuous integration has been migrated from Travis-CI + AppVeyor to GitHub actions.

as.POSIXlt() now converts NULL to an empty POSIXlt object, so a test that was previously checking for an error failed. That test has been fixed (#33, @zkamvar)

change_week_start() allows the user to change the week_start attribute of an aweek object, adjusting the weeks to match the new attribute accordingly.
get_aweek() can generate aweek objects from a vector of week numbers. It has the ability to take into account different week start times.
get_date() is similar to get_aweek(), but returns dates instead.
as.aweek() allows users to create aweek object directly from characters with validation. It also allows for dates by passing to date2week().
as.data.frame.aweek() is a new function that allows aweek objects to be directly incorporated into data frames.
as.list.aweek() will now preserve the aweek structure in lists
trunc.aweek() will truncate the day to the first day of the week.
rep.aweek() allows repeating aweek characters.
factor_aweek() allows the user to create aggregated aweek objects on the fly.

There are a couple of breaking changes coming to aweek that will improve stability by removing unclear coercion methods (see https://github.com/reconhub/aweek/issues/20).

It is no longer possible to combine aweek objects if they do not share the same week_start attribute. This will result in an error informing the user to adjust the week_start attribute with the change_week_start() function.
Factors will no longer coerce factors when combining aweek objects.
Using date2week() with factor = TRUE and floor_day = FALSE now throws an error instead of a warning (as prophesized in #13).

The vignette has been updated to include an explanation of the underlying week calculation from date.
The aweek class documentation has been updated to detail the different elements of the object and the calculations.
Package documentation package?aweek has been added for an introduction.

More checks that weekdays and weeks are within the correct bounds have been added.
as.Date.aweek has been simplified to no longer rely on regex since the aweek class is standard.
The internal get_wday() has been vastly simplified with improved speed.

The week_start argument now defaults to the global option aweek.week_start, which will be a number from 1 to 7, representing the days of the week in the ISO 8601 standard.
set_week_start() is a convenience allowing the user to set the default aweek.week_start option via integer or character input.
get_week_start() is a wrapper for getOption("aweek.week_start", 1L) and attr(w, "week_start") for aweek objects.

Simplified conversion to factors.
Using factor = TRUE without floor_day = TRUE will now issue a message indicating that this is deprecated in future versions of aweek (see #13).

Fix bug where NAs threw errors in the dates (found: @aspina7, #12)
as.data.frame.aweek() will now convert aweek objects to columns of data frames without losing class or attributes
The introduction vignette has been updated to reflect this change.

Subsetting and concatenating methods added to the aweek class (see #1)
Documentation divided into smaller chunks
as.POSIXlt() bug where tz was not being passed was fixed.
date2week(): an error is now issued if users specify non-ISO 8601 dates OR don’t specify a format option. (found: @scottyaz, #2)
Best practices added to vignette
Fix test that would fail every seven days on CRAN

date2week() and week2date() can now take days represented as characters in the current or English locale.

date2week() gains a factor argument, which will automatically compute the levels within the date range.

date2week() now properly accounts for dates in December that occur in the first week of the next year.

floor_day now truncates the week instead changing the last digit to 1 for aesthetics. (Thanks to @aspina7 for the suggestion) q print.aweek() now displays the day of the week in the current locale.