## clock 0.6.1

• date_seq() and the seq() methods for the calendar, time point, and duration types now allow from > to when by > 0. This now results in a size zero result rather than an error, which is more in line with rlang::seq2() and generally has more useful programmatic properties (#282).

• The sys-time method for as.POSIXct() now correctly promotes to a precision of at least seconds before attempting the conversion. This matches the behavior of the naive-time method (#278).

• Removed the dependency on ellipsis in favor of the equivalent functions in rlang (#288).

• Updated tests related to writing UTF-8 on Windows and testthat 3.1.2 (#287).

• Updated all snapshot tests to use rlang 1.0.0 (#285).

• tzdb >=0.3.0 is now required to get access to the latest time zone database information (2022a).

• vctrs >=0.4.1 and rlang >=1.0.4 are now required (#297).

• cpp11 >=0.4.2 is now required to ensure that a fix related to unwind protection is included.

• R >=3.4.0 is now required. This is consistent with the standards of the tidyverse.

## clock 0.6.0

CRAN release: 2021-12-02

• New date_count_between(), calendar_count_between(), and time_point_count_between() for computing the number of units of time between two dates (i.e. the number of years, months, days, or seconds). This has a number of uses, like computing the age of an individual in years, or determining the number of weeks that have passed since the start of the year (#266).

• Modulus is now defined between a duration vector and an integer vector through <duration> %% <integer>. This returns a duration vector containing the remainder of the division (#273).

• Integer division is now defined for two duration objects through <duration> %/% <duration>. This always returns an integer vector, so be aware that using very precise duration objects (like nanoseconds) can easily generate a division result that is outside the range of an integer. In that case, an NA is returned with a warning.

## clock 0.5.0

CRAN release: 2021-10-29

• New date_time_parse_RFC_3339() and sys_time_parse_RFC_3339() for parsing date-time strings in the RFC 3339 format. This format is a subset of ISO 8601 representing the most common date-time formats seen in internet protocols, and is particularly useful for parsing date-time strings returned by an API. The default format parses strings like "2019-01-01T01:02:03Z" but can be adjusted to parse a numeric offset from UTC with the offset argument, which can parse strings like "2019-01-01T01:02:03-04:30" (#254).

• To align more with RFC 3339 and ISO 8601 standards, the default formats used in many of the date formatting and parsing functions have been slightly altered. The following changes have been made:

• Date-times (POSIXct):

• date_format() now prints a T between the date and time.

• date_time_parse_complete() now expects a T between the date and time by default.

• Sys-times:

• format() and as.character() now print a T between the date and time.

• sys_time_parse() now expects a T between the date and time by default.

• Naive-times:

• format() and as.character() now print a T between the date and time.

• naive_time_parse() now expects a T between the date and time by default.

• Zoned-times:

• format() and as.character() now print a T between the date and time.

• zoned_time_parse_complete() now expects a T between the date and time by default.

• Calendars:

• format() and as.character() now print a T between the date and time.

• year_month_day_parse() now expects a T between the date and time by default.

• Further improved documentation of undefined behavior resulting from attempting to parse sub-daily components of a string that is intended to be parsed into a Date (#258).

• Bumped required minimum version of tzdb to 0.2.0 to get access to the latest time zone database information (2021e) and to fix a Unicode bug on Windows.

## clock 0.4.1

CRAN release: 2021-09-21

• Updated a test related to upcoming changes in testthat.

## clock 0.4.0

CRAN release: 2021-07-22

• New date_start() and date_end() for computing the date at the start or end of a particular precision, such as the “end of the month” or the “start of the year”. These are powered by calendar_start() and calendar_end(), which allow for even more flexible calendar-specific boundary generation, such as the “last moment in the fiscal quarter” (#232).

• New invalid_remove() for removing invalid dates. This is just a wrapper around x[!invalid_detect(x)], but works nicely with the pipe (#229).

• All clock types now support is.nan(), is.finite(), and is.infinite(). Additionally, duration types now support abs() and sign() (#235).

• tzdb 0.1.2 is now required, which fixes compilation issues on RHEL7/Centos (#234).

## clock 0.3.1

CRAN release: 2021-06-28

• Parsing into a date-time type that is coarser than the original string is now considered ambiguous and undefined behavior. For example, parsing a string with fractional seconds using date_time_parse(x) or naive_time_parse(x, precision = "second") is no longer considered correct. Instead, if you only require second precision from such a string, parse the full string, with fractional seconds, into a clock type that can handle them, then round to seconds using whatever rounding convention is required for your use case, such as time_point_floor() (#230).

For example:

x <- c("2019-01-01 00:00:59.123", "2019-01-01 00:00:59.556")

x <- naive_time_parse(x, precision = "millisecond")
x
#> <time_point<naive><millisecond>[2]>
#> [1] "2019-01-01 00:00:59.123" "2019-01-01 00:00:59.556"

x <- time_point_round(x, "second")
x
#> <time_point<naive><second>[2]>
#> [1] "2019-01-01 00:00:59" "2019-01-01 00:01:00"

as_date_time(x, "America/New_York")
#> [1] "2019-01-01 00:00:59 EST" "2019-01-01 00:01:00 EST"
• Preemptively updated tests related to upcoming changes in testthat (#236).

## clock 0.3.0

CRAN release: 2021-04-22

• New date_seq() for generating date and date-time sequences (#218).

• clock now uses the tzdb package to access the date library’s API. This means that the experimental API that was to be used for vroom has been removed in favor of using the one exposed in tzdb.

• zone_database_names() and zone_database_version() have been removed in favor of re-exporting tzdb_names() and tzdb_version() from the tzdb package.

## clock 0.2.0

CRAN release: 2021-04-12

• clock now interprets R’s Date class as naive-time rather than sys-time. This means that it no longer assumes that Date has an implied time zone of UTC (#203). This generally aligns better with how users think Date should work. This resulted in the following changes:

• date_zone() now errors with Date input, as naive-times do not have a specified time zone.

• date_parse() now parses into a naive-time, rather than a sys-time, before converting to Date. This means that %z and %Z are now completely ignored.

• The Date method for date_format() now uses the naive-time format() method rather than the zoned-time one. This means that %z and %Z are no longer valid format commands.

• The zoned-time method for as.Date() now converts to Date through an intermediate naive-time, rather than a sys-time. This means that the printed date will always be retained, which is generally what is expected.

• The Date method for as_zoned_time() now converts to zoned-time through an intermediate naive-time, rather than a sys-time. This means that the printed date will always attempt to be retained, if possible, which is generally what is expected. In the rare case that daylight saving time makes a direct conversion impossible, nonexistent and ambiguous can be used to resolve any issues.

• New as_date() and as_date_time() for converting to Date and POSIXct respectively. Unlike as.Date() and as.POSIXct(), these functions always treat Date as a naive-time type, which results in more consistent and intuitive conversions. Note that as_date() does conflict with lubridate::as_date(), and the lubridate version handles Dates differently (#209).

• Added two new convenient helpers (#197):

• date_today() for getting the current date (Date)

• date_now() for getting the current date-time (POSIXct)

• Fixed a bug where converting from a time point to a Date or POSIXct could round incorrectly (#205).

• Errors resulting from invalid dates or nonexistent/ambiguous times are now a little nicer to read through the usage of an info bullet (#200).

• Formatting a naive-time with %Z or %z now warns that there were format failures (#204).

• Fixed a Solaris ambiguous behavior issue from calling pow(int, int).

• Linking against cpp11 0.2.7 is now required to fix a rare memory leak issue.

• Exposed an extremely experimental and limited C++ API for vroom (#322).

## clock 0.1.0

CRAN release: 2021-03-31

• Added a NEWS.md file to track changes to the package.