Remove travis and replace badge with GH actions

Fix typos

.github/workflows/tests-workflow.yml

@@ -0,0 +1,47 @@
+name: qdate tests and dialyzer
+on: push
+
+jobs:
+  linux:
+    name: OTP ${{ matrix.otp_version }}
+    runs-on: ${{ matrix.os }}
+    continue-on-error: true
+
+    strategy:
+      matrix:
+        include:
+          - os: ubuntu-22.04
+            otp_version: '27.x'
+            rebar3_version: "3.24.0"
+          - os: ubuntu-22.04
+            otp_version: '27.x'
+            rebar3_version: "3.23.0"
+          - os: ubuntu-22.04
+            otp_version: '26.x'
+            rebar3_version: "3.22.1"
+          - os: ubuntu-22.04
+            otp_version: '25.x'
+            rebar3_version: "3.22.1"
+          - os: ubuntu-22.04
+            otp_version: '24.x'
+            rebar3_version: "3.22.1"
+          - os: ubuntu-20.04
+            otp_version: '23.x'
+            rebar3_version: "3.19.0"
+
+    steps:
+      - name: Install OTP ${{matrix.otp_version}}
+        uses: erlef/setup-beam@v1
+        with:
+          version-type: loose
+          otp-version: ${{ matrix.otp_version}}
+          rebar3-version: ${{ matrix.rebar3_version}}
+
+      - name: Checkout qdate
+        uses: actions/checkout@v4
+
+      - name: Run Tests
+        run: make test
+
+      - name: Run Dialyzer
+        run: make dialyzer

.gitignore

@@ -1,8 +1,10 @@
 *~
 *.beam
 *.sw?
+*.iml
 deps/
 ebin/
 .eunit/
+.idea/
 _build
-rebar.lock
+doc/

.travis.yml

@@ -1,14 +0,0 @@
-language: erlang
-script: "make test"
-otp_release:
-  - 22.0
-  - 21.2
-  - 21.0
-  - 20.0
-  - 19.0
-  - 18.0
-  - 17.4
-  - 17.0
-  - R16B
-  - R15B03
-before_script: "sudo apt-get --yes --force-yes install libpam-runtime python-software-properties"

CHANGELOG.markdown

@@ -1,3 +1,32 @@
+## 0.7.3
+
+* Remove the `?else` macro.
+
+## 0.7.2
+
+* Update the error message when qdate is not started with some better instructions.
+* Some minor updates for hex.pm
+* Removed the `erlnow()` warning
+* Fix some typos in the documentation
+* Update the makefile to use [rebar3.mk](https://rebar3.mk)
+* Skipped 0.7.1 only because there was a partially tagged 0.7.1 for a while,
+  but was never published to hex. Just to ensure upgrades are easier, I just skipped
+  a proper 0.7.1 release
+
+## 0.7.0
+
+* Re-introduce the qdate server for storing qdate timezones, formats, and parsers,
+  rather than overloading the `application` env vars (since the `application`
+  module only wants keys to be atoms).
+* Convert to using `qdate_localtime` 1.2.0 (which passes dialyzer checks)
+* `qdate` is passing dialyzer again
+
+## 0.6.0
+
+* Add `age` and `age_days` functions
+* Add option to preserve millisecond accuracy in date parsing and formatting (@Leonardb)
+
+
 ## 0.5.0
 
 * Add `range_X` functions for getting a list of dates/times within a range
@@ -8,7 +37,7 @@
   just the opposite of `beginning_X`)
 * Add `between/[2,3,5]` functions for computing whether a date/time is between
   two others.
-* Update to rebar3 and add hex compatability. (@Licenser)
+* Update to rebar3 and add hex compatibility. (@Licenser)
 * Properly add dependent apps to .app.src (@Licenser)
 * Add an optional "relative date/time parser".
 * Fix: Ensure `get_timezone()` returns the default timezone (from config) if it

Makefile

@@ -1,21 +1,41 @@
-REBAR = $(shell pwd)/rebar3
-
 all: compile
 
-compile:
+# Check if rebar3.mk exists, and if not, download it
+ifeq ("$(wildcard rebar3.mk)","")
+$(shell curl -O https://raw.githubusercontent.com/choptastic/rebar3.mk/master/rebar3.mk)
+endif
+
+# rebar3.mk adds a new rebar3 rule to your Makefile
+# (see https://github.com/choptastic/rebar3.mk) for full info
+include rebar3.mk
+
+compile: rebar3
 	$(REBAR) compile
 
-update:
+update: rebar3
 	$(REBAR) update
 
-test: compile
+test:
-	$(REBAR) eunit
+	EUNIT=1 $(REBAR) compile
+	EUNIT=1 $(REBAR) eunit
 
-run:
+dialyzer: compile
+	DIALYZER=1 $(REBAR) dialyzer
+
+dev:
+	mkdir -p _checkouts
+	cd _checkouts; git clone https://github.com/choptastic/qdate_localtime
+
+
+run: rebar3
 	$(REBAR) shell
 
-publish:
+push_tags:
-	$(REBAR) as pkg upgrade
+	git push --tag
-	$(REBAR) as pkg hex publish
+
-	$(REBAR) upgrade
+pull_tags:
+	git pull --tag
+
+publish: rebar3 pull_tags
+	$(REBAR) hex publish
 

README.md

@@ -1,6 +1,6 @@
 # qdate - Erlang Date and Timezone Library
 
-[![Build Status](https://travis-ci.org/choptastic/qdate.png?branch=master)](https://travis-ci.org/choptastic/qdate)
+[![qdate tests and dialyzer](https://github.com/choptastic/qdate/actions/workflows/tests-workflow.yml/badge.svg)](https://github.com/choptastic/qdate/actions/workflows/tests-workflow.yml)
 
 ## Purpose
 
@@ -107,7 +107,7 @@ will infer the timezone in the following order.
 
 #### Disambiguating Ambiguous Timezone Conversions
 
-Sometimes, when youre converting a datetime from one timezone to another, there
+Sometimes, when you're converting a datetime from one timezone to another, there
 are potentially two different results if the conversion happens to land on in a
 timezone that's in the middle of a Daylight Saving conversion.  For example,
 converting "11-Nov-2013 1:00:am" in "America/New York" to "GMT" could be both
@@ -536,7 +536,7 @@ qdate:between(qdate:add_minutes(-15), Date, qdate:add_minutes(15)).
 
 %% But, you don't have to: if that's a common format you use in your
 %% application, you can register your format with the `qdate` server, and then
-%% easiy refer to that format by its key.
+%% easily refer to that format by its key.
 
 %% So let's take that format and register it
 16> qdate:register_format(longdate, "l, F jS, Y g:i A T").
@@ -720,7 +720,7 @@ the week" calculation.  This has three forms, specifically:
      7=Sunday).
    + `beginning_week(DayOfWeek, Date)` - Calculates the beginning of the week
      based on the provided `DayOfWeek`. Valid values for DayOfWeek are the
-     integers 1-7 or the atom verions of the days of the week. Specifically:
+     integers 1-7 or the atom versions of the days of the week. Specifically:
 	 
      * Monday: `1 | monday | mon`
      * Tuesday: `2 | tuesday | tue`
@@ -845,6 +845,16 @@ with qdate:
 
 Also note that the range functions are *inclusive*.
 
+
+## Age Comparison
+
+There are two main comparisons right now, age in years, and age in days.
+
+  + `age(Date)` - Number of years since `Date`
+  + `age(FromDate, ToDate)` - Number of years between `FromDate` to `ToDate`
+  + `age_days(Date)` - Number of full days since `Date` (for example from `2pm` yesterday to `1:59pm` today is still 0.
+  + `age_days(FromDate, ToDate)` - Number of full days between `FromDate` and `ToDate`.
+
 ## Configuration Sample
 
 There is a sample configuration file can be found in the root of the qdate
@@ -879,7 +889,6 @@ See [CHANGELOG.markdown](https://github.com/choptastic/qdate/blob/master/CHANGEL
 + Add `-spec` and `-type` info for dialyzer
 + Research the viability of [ezic](https://github.com/drfloob/ezic) for a
   timezone backend replacement for `erlang_localtime`.
-+ Add age calculation stuff: `age_years(Date)`, `age_minutes(Date)`, etc.
 
 ## Conclusion
 

qdate.config

@@ -11,5 +11,10 @@
 
     %% See readme section here:
     %% https://github.com/choptastic/qdate#about-backwards-compatibility-with-ec_date-and-deterministic-parsing
-    {deterministic_parsing, {zero, zero}}
+    {deterministic_parsing, {zero, zero}},
+
+    %% Preserve Milliseconds in parsing
+    %% Changes the return for qdate:to_date to include any Ms value
+    %% and also changes the return of to_string to include the Ms value
+    {preserve_ms, false}
 ]}].

rebar.config

@@ -2,8 +2,23 @@
 %% vim:ts=4 sw=4 et ft=erlang
 {cover_enabled, true}.
 
+{dialyzer, [
+    {exclude_apps, []},
+    {warnings, []}
+]}.
+
 {deps,
  [
   erlware_commons,
-  qdate_localtime
+  {qdate_localtime, "~> 1.2.0"}
  ]}.
+
+{project_plugins, [rebar3_ex_doc]}.
+
+{hex, [{doc, ex_doc}]}.
+
+{ex_doc, [
+          {source_url, <<"https://github.com/choptastic/qdate">>},
+          {extras, [<<"README.md">>, <<"LICENSE.md">>]},
+          {main, <<"readme">>}]}.
+

rebar.config.script

@@ -9,7 +9,7 @@ case erlang:function_exported(rebar3, main, 1) of
         %% Rebuild deps, possibly including those that have been moved to
         %% profiles
         [{deps, [
-            {erlware_commons, "", {git, "git://github.com/erlware/erlware_commons", {tag, "v1.3.1"}}}, %% this is the version of erlware_commons that works until erlware tags a new version
+            {erlware_commons, "", {git, "https://github.com/erlware/erlware_commons", {tag, "v1.5.0"}}}, %% this is the version of erlware_commons that works until erlware tags a new version
-            {qdate_localtime, "", {git, "git://github.com/choptastic/qdate_localtime", {tag, "1.1.0"}}}
+            {qdate_localtime, "", {git, "https://github.com/choptastic/qdate_localtime", {tag, "1.1.0"}}}
         ]} | lists:keydelete(deps, 1, CONFIG)]
 end.

rebar.lock

@@ -0,0 +1,14 @@
+{"1.2.0",
+[{<<"cf">>,{pkg,<<"cf">>,<<"0.3.1">>},1},
+ {<<"erlware_commons">>,{pkg,<<"erlware_commons">>,<<"1.6.0">>},0},
+ {<<"qdate_localtime">>,{pkg,<<"qdate_localtime">>,<<"1.2.1">>},0}]}.
+[
+{pkg_hash,[
+ {<<"cf">>, <<"5CB902239476E141EA70A740340233782D363A31EEA8AD37049561542E6CD641">>},
+ {<<"erlware_commons">>, <<"E0DA62F91E65DEFAE28BB450DDC3C24E85ECB99B926F857CDC6ED8E7DD7076B4">>},
+ {<<"qdate_localtime">>, <<"72E1034DC6B7FEE8F588281EDDD0BD0DC5260005D758052F50634D265D382C18">>}]},
+{pkg_hash_ext,[
+ {<<"cf">>, <<"315E8D447D3A4B02BCDBFA397AD03BBB988A6E0AA6F44D3ADD0F4E3C3BF97672">>},
+ {<<"erlware_commons">>, <<"B57C299C39A2992A8C413F9D2C1B8A20061310FB4432B0EEE5E4C4DF7AAA0AA3">>},
+ {<<"qdate_localtime">>, <<"1109958D205C65C595C8C5694CB83EBAF2DBE770CF902E4DCE8AFB2C4123764D">>}]}
+].

src/qdate.app.src

@@ -1,17 +1,17 @@
 {application, qdate,
  [
   {description, "Simple Date and Timezone handling for Erlang"},
-  {vsn, "0.5.0"},
+  {vsn, git},
   {registered, []},
   {applications, [
                   kernel,
+                  stdlib,
                   qdate_localtime,
-                  erlware_commons,
+                  erlware_commons
-                  stdlib
                  ]},
-  {modules, [qdate, qdate_srv]},
+  {modules, [qdate, qdate_srv, qdate_sup, qdate_app]},
   {env, []},
-  {contributors, ["Jesse Gumm"]},
   {licenses, ["MIT"]},
+  {mod, {qdate_app, []}},
   {links, [{"Github", "https://github.com/choptastic/qdate"}]}
  ]}.

src/qdate.erl

@@ -1,9 +1,11 @@
 % vim: ts=4 sw=4 et
-% Copyright (c) 2013-2019 Jesse Gumm
+% Copyright (c) 2013-2023 Jesse Gumm
 % See LICENSE for licensing information.
 %
 -module(qdate).
 
+%-compile(export_all).
+
 -export([
     start/0,
     stop/0
@@ -101,6 +103,13 @@
     range_years/3
 ]).
 
+-export([
+    age/1,
+    age/2,
+    age_days/1,
+    age_days/2
+]).
+
 -export([
     register_parser/2,
     register_parser/1,
@@ -131,6 +140,13 @@
     parse/1
 ]).
 
+-type qdate() :: any().
+-type datetime() :: {{integer(), integer(), integer()}, {integer(), integer(), integer()}} |
+                    {{integer(), integer(), integer()}, {integer(), integer(), integer(), integer()}}.
+-type erlnow() :: {integer(), integer(), integer()}.
+-type binary_or_string() :: binary() | string().
+-type disambiguate() :: prefer_standard | prefer_daylight | both.
+
 %% erlang:get_stacktrace/0 is deprecated in OTP 21
 -ifndef(OTP_RELEASE).
 -define(WITH_STACKTRACE(T, R, S), T:R -> S = erlang:get_stacktrace(), ).
@@ -146,10 +162,10 @@
 
 -define(DETERMINE_TZ, determine_timezone()).
 -define(DEFAULT_DISAMBIG, prefer_standard).
--define(else, true).
+
 
 start() ->
-    application:load(qdate).
+    application:ensure_all_started(qdate).
 
 stop() ->
     ok.
@@ -163,6 +179,7 @@ to_string(Format, Date) ->
 to_string(Format, ToTZ, Date) ->
     to_string(Format, ToTZ, ?DEFAULT_DISAMBIG, Date).
 
+-spec to_string(Format :: any(), ToTZ :: any(), Disambiguate :: disambiguate(), Date :: qdate()) -> binary_or_string() | {ambiguous, binary_or_string() , binary_or_string()}.
 to_string(FormatKey, ToTZ, Disambiguate, Date) when is_atom(FormatKey) orelse is_tuple(FormatKey) ->
     Format = case qdate_srv:get_format(FormatKey) of
         undefined -> throw({undefined_format_key,FormatKey});
@@ -229,7 +246,13 @@ to_string_worker([$r | RestFormat], ToTZ, Disamb, Date) ->
     to_string_worker(NewFormat, ToTZ, Disamb, Date) ++ to_string_worker(RestFormat, ToTZ, Disamb, Date);
 to_string_worker([$c | RestFormat], ToTZ, Disamb, Date) ->
     Format1 = "Y-m-d",
-    Format2 = "H:i:sP",
+    Format2 = case Date of
+                  {_, {_,_,_,_}} ->
+                      %% Have milliseconds
+                      "H:i:s.fP";
+                  _ ->
+                      "H:i:sP"
+              end,
     to_string_worker(Format1, ToTZ, Disamb, Date) 
             ++ "T" 
             ++ to_string_worker(Format2, ToTZ, Disamb, Date) 
@@ -280,6 +303,7 @@ to_date(RawDate) ->
 to_date(ToTZ, RawDate) ->
     to_date(ToTZ, ?DEFAULT_DISAMBIG, RawDate).
 
+-spec to_date(ToTZ :: any(), Disambiguate :: disambiguate(), RawDate :: any()) -> {ambiguous, datetime(), datetime()} | datetime().
 to_date(ToTZ, Disambiguate, RawDate) when is_binary(RawDate) ->
     to_date(ToTZ, Disambiguate, binary_to_list(RawDate));
 to_date(ToTZ, Disambiguate, RawDate) when is_binary(ToTZ) ->
@@ -294,9 +318,13 @@ to_date(ToTZ, Disambiguate, RawDate)  ->
         {ParsedDate,ParsedTZ} ->
             {ParsedDate,ParsedTZ}
     end,
+    PreserveMs = preserve_ms(),
     try raw_to_date(RawDate3) of
         D={{_,_,_},{_,_,_}} ->
             date_tz_to_tz(D, Disambiguate, FromTZ, ToTZ);
+        {{Year, Month, Date},{Hour,Minute,Second,Millis}} when PreserveMs ->
+            {ODate, {OHour,OMinute,OSecond}} = date_tz_to_tz({{Year, Month, Date},{Hour,Minute,Second}}, Disambiguate, FromTZ, ToTZ),
+            {ODate, {OHour,OMinute,OSecond, Millis}};
         {{Year, Month, Date},{Hour,Minute,Second,_Millis}} ->
             date_tz_to_tz({{Year, Month, Date},{Hour,Minute,Second}}, Disambiguate, FromTZ, ToTZ)
     catch
@@ -333,9 +361,9 @@ get_deterministic_datetime() ->
 to_unixtime(Date) ->
     to_unixtime(?DEFAULT_DISAMBIG, Date).
 
+-spec to_unixtime(Disamb :: disambiguate(), qdate()) -> {ambiguous, integer(), integer()} | integer().
 to_unixtime(_, Unixtime) when is_integer(Unixtime) ->
     Unixtime;
-
 to_unixtime(_, {MegaSecs,Secs,_}) when is_integer(MegaSecs), is_integer(Secs) ->
     MegaSecs*1000000 + Secs;
 to_unixtime(Disamb, ToParse) ->
@@ -355,11 +383,12 @@ unixtime() ->
 to_now(Date) ->
     to_now(?DEFAULT_DISAMBIG, Date).
 
+-spec to_now(Disamb :: disambiguate(), qdate()) -> erlnow() | {ambiguous, erlnow(), erlnow()}.
 to_now(_, Now = {_,_,_}) ->
     Now;
 to_now(Disamb, ToParse) ->
     case to_unixtime(Disamb, ToParse) of
-        {ambiguous, Standard, Daylight} ->
+        {ambiguous, Standard, Daylight} when is_integer(Standard), is_integer(Daylight) ->
             {ambiguous, 
                 unixtime_to_now(Standard),
                 unixtime_to_now(Daylight)};
@@ -505,6 +534,7 @@ end_week(BeginningDayOfWeek, Date) ->
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%    Comparisons     %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 
+-spec compare(A :: qdate(), B :: qdate()) -> integer().
 compare(A, B) ->
     NowA = to_now(A),
     NowB = to_now(B),
@@ -514,6 +544,7 @@ compare(A, B) ->
         NowA > NowB -> 1
     end.
 
+-spec compare(A :: qdate(), Op :: atom(), B :: qdate()) -> boolean().
 compare(A, Op, B) ->
     Comp = compare(A, B),
     case Op of
@@ -558,7 +589,7 @@ sort(Op, List) ->
 sort(Op, List, Opts) ->
     NonDateOpt = proplists:get_value(non_dates, Opts, back),
     WithNorm = add_sort_normalization(List, NonDateOpt),
-    SortFun = make_sort_fun(Op, Opts),
+    SortFun = make_sort_fun(Op, NonDateOpt),
     Sorted = lists:sort(SortFun, WithNorm),
     strip_sort_normalization(Sorted).
 
@@ -577,6 +608,7 @@ add_sort_normalization(List, NonDateOpt) ->
 strip_sort_normalization(List) ->
     [Date || {_, Date} <- List].
 
+-spec make_sort_fun(Op :: atom(), NonDateOpt :: front | back) -> fun().
 make_sort_fun(Op, NonDateOpt) ->
     DateComp = sort_op_comp_fun(Op),
     
@@ -670,6 +702,15 @@ add_years(Years, Date) ->
 add_years(Years) ->
     add_years(Years, os:timestamp()).
 
+-type unit() :: second | seconds |
+                minute | minutes |
+                hour | hours |
+                day | days |
+                week | weeks |
+                month | months |
+                year | years.
+
+-spec add_unit(Unit :: unit(), Value :: integer(), Date :: qdate()) -> qdate().
 add_unit(second, Value, Date) ->
     add_unit(seconds, Value, Date);
 add_unit(seconds, Value, Date) ->
@@ -768,6 +809,42 @@ fmid({Y, M, D}) when D < 1 ->
 fmid(Date) ->
     Date.
 
+age(Birth) ->
+    age(Birth, os:timestamp()).
+
+age(Birth, Now) ->
+    %% B=Birth
+    {{BY, BM, BD}, _} = to_date(Birth),
+    %% C=Current
+    {{CY, CM, CD}, _} = to_date(Now),
+    if
+        (CM > BM);
+        (CM == BM andalso CD >= BD)
+            -> CY - BY;
+        true ->
+            (CY - BY) - 1
+    end.
+
+age_days(Birth) ->
+    age_days(Birth, os:timestamp()).
+
+age_days(Birth, Now) ->
+    case {to_date(Birth), to_date(Now)} of
+        {{SameDay, _}, {SameDay, _}} ->
+            0;
+        {{BirthDate, BirthTime}, {NowDate, NowTime}} ->
+            BirthDays = calendar:date_to_gregorian_days(BirthDate),
+            NowDays = calendar:date_to_gregorian_days(NowDate),
+            DiffDays = NowDays - BirthDays,
+            if
+                NowTime >= BirthTime ->
+                    DiffDays;
+                true ->
+                    DiffDays-1
+            end
+    end.
+
+
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%      Ranges        %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
@@ -962,6 +1039,8 @@ extract_timezone_helper(RevDate, [TZ | TZs]) when length(RevDate) >= length(TZ)
 extract_timezone_helper(RevDate, [_TZ | TZs]) ->
     extract_timezone_helper(RevDate, TZs).
 
+preserve_ms() ->
+    application:get_env(qdate, preserve_ms, false).
 
 %% This is the timezone only if the qdate application variable 
 %% "default_timezone" isn't set or is set to undefined.
@@ -985,6 +1064,8 @@ determine_timezone() ->
 %% If FromTZ is an integer, then it's an integer that represents the number of minutes
 %% relative to GMT. So we convert the date to GMT based on that number, then we can
 %% do the other timezone conversion.
+-spec date_tz_to_tz(Date :: datetime(), Disambiguate :: disambiguate(), FromTZ :: any(), ToTZ :: any()) ->
+    datetime() | {ambiguous, datetime(), datetime()}.
 date_tz_to_tz(Date, Disambiguate, FromTZ, ToTZ) when is_integer(FromTZ) ->
     NewDate = localtime:adjust_datetime(Date, FromTZ),
     date_tz_to_tz(NewDate, Disambiguate, "GMT", ToTZ);
@@ -999,13 +1080,14 @@ date_tz_to_tz(Date, Disambiguate, FromTZ, ToTZ) ->
             date_tz_to_tz_both(Date, FromTZ, ToTZ)
     end.
 
+-spec date_tz_to_tz_both(Date :: datetime(), FromTZ :: string(), ToTZ :: string()) -> datetime() | {ambiguous, datetime(), datetime()}.
 date_tz_to_tz_both(Date, FromTZ, ToTZ) ->
     Standard = localtime:local_to_local(Date, FromTZ, ToTZ),
     Daylight = localtime:local_to_local_dst(Date, FromTZ, ToTZ),
     if
         Standard=:=Daylight ->
             Standard;
-        ?else -> 
+        true -> 
             {ambiguous, Standard, Daylight}
     end.           
 
@@ -1124,6 +1206,8 @@ flooring(N) when N < 0 ->
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%  TESTS  %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 
+-ifdef(EUNIT).
+
 -include_lib("eunit/include/eunit.hrl").
 
 %% emulates as if a forum-type website has a Site tz, and a user-specified tz
@@ -1151,6 +1235,30 @@ tz_test_() ->
         end
     }.
 
+tz_preserve_ms_true_test_() ->
+    {
+        setup,
+        fun start_test/0,
+        fun stop_test/1,
+        fun(SetupData) ->
+            {inorder,[
+                preserve_ms_true_tests(SetupData)
+            ]}
+        end
+    }.
+
+tz_preserve_ms_false_test_() ->
+    {
+        setup,
+        fun start_test/0,
+        fun stop_test/1,
+        fun(SetupData) ->
+            {inorder,[
+                preserve_ms_false_tests(SetupData)
+            ]}
+        end
+    }.
+
 test_deterministic_parser(_) ->
     {inorder, [
         ?_assertEqual(ok, application:set_env(qdate, deterministic_parsing, {now, now})),
@@ -1340,13 +1448,45 @@ arith_tests(_) ->
         ?_assertEqual({{2017,1,3},{0,0,0}}, beginning_week(2, {{2017,1,4},{0,0,0}})),
         ?_assertEqual({{2016,12,29},{0,0,0}}, beginning_week(4, {{2017,1,4},{0,0,0}})),
         ?_assertEqual({{2016,12,31},{0,0,0}}, beginning_week(6, {{2017,1,6},{0,0,0}})),
-        ?_assertEqual({{2017,1,1},{0,0,0}}, beginning_week(7, {{2017,1,6},{0,0,0}}))
+        ?_assertEqual({{2017,1,1},{0,0,0}}, beginning_week(7, {{2017,1,6},{0,0,0}})),
+
+        ?_assertEqual(0, age("1981-01-15", "1981-12-31")),
+        ?_assertEqual(39, age("1981-01-15", "2020-01-15")),
+        ?_assertEqual(39, age("1981-01-15", "2020-01-15 12am")),
+        ?_assertEqual(38, age("1981-01-15", "2020-01-14")),
+        ?_assertEqual(38, age("1981-01-15", "2020-01-14 11:59pm")),
+
+        %% checking pre-unix-epoch
+        ?_assertEqual(100, age("1901-01-01","2001-01-01")),
+        ?_assertEqual(20, age("1900-01-01", "1920-01-01")),
+        
+        ?_assertEqual(0, age_days("2020-11-20 12am","2020-11-20 11:59:59pm")),
+        ?_assertEqual(1, age_days("2020-11-19 11:59:59pm","2020-11-20 11:59:59pm")),
+        ?_assertEqual(7, age_days("2020-11-20","2020-11-27")),
+        ?_assertEqual(7, age_days("2020-11-27","2020-12-04"))
 
     ]}.
 
+preserve_ms_true_tests(_) ->
+    application:set_env(qdate, preserve_ms, true),
+    {inorder, [
+      ?_assertEqual({{2021,5,8},{23,0,16,472000}}, qdate:to_date(<<"UTC">>,<<"2021-5-09 0:0:16.472+01:00">>)),
+      ?_assertEqual(<<"2021-05-08T23:00:16.472000+00:00">>, qdate:to_string(<<"Y-m-d\\TH:i:s.fP">>, <<"UTC">>,<<"2021-5-09 0:0:16.472+01:00">>)),
+      ?_assertEqual(<<"2021-05-08T23:00:16+00:00">>, qdate:to_string(<<"Y-m-d\\TH:i:sP">>, <<"UTC">>,<<"2021-5-09 0:0:16.472+01:00">>)),
+      ?_assertEqual(<<"2021-05-08T23:00:16.472000+00:00">>, qdate:to_string(<<"c">>, <<"UTC">>,<<"2021-5-09 0:0:16.472+01:00">>))
+    ]}.
+
+preserve_ms_false_tests(_) ->
+    application:set_env(qdate, preserve_ms, false),
+    {inorder, [
+        ?_assertEqual({{2021,5,8},{23,0,16}}, qdate:to_date(<<"UTC">>,<<"2021-5-09 0:0:16.472+01:00">>)),
+        ?_assertEqual(<<"2021-05-08T23:00:16.0+00:00">>, qdate:to_string(<<"Y-m-d\\TH:i:s.fP">>, <<"UTC">>,<<"2021-5-09 0:0:16.472+01:00">>)),
+        ?_assertEqual(<<"2021-05-08T23:00:16+00:00">>, qdate:to_string(<<"Y-m-d\\TH:i:sP">>, <<"UTC">>,<<"2021-5-09 0:0:16.472+01:00">>)),
+        ?_assertEqual(<<"2021-05-08T23:00:16+00:00">>, qdate:to_string(<<"c">>, <<"UTC">>,<<"2021-5-09 0:0:16.472+01:00">>))
+    ]}.
 
 start_test() ->
-    application:start(qdate),
+    qdate:start(),
     set_timezone(?SELF_TZ),
     set_timezone(?SITE_KEY,?SITE_TZ),
     set_timezone(?USER_KEY,?USER_TZ),
@@ -1391,3 +1531,5 @@ microsoft_parser(_) ->
 
 stop_test(_) ->
     ok.
+
+-endif.

src/qdate_app.erl

@@ -0,0 +1,15 @@
+-module(qdate_app).
+
+-behaviour(application).
+
+%% Application callbacks
+-export([start/2, stop/1]).
+
+start(_StartType, _StartArgs) ->
+    qdate_sup:start_link().
+
+
+stop(_State) ->
+    ok.
+
+

src/qdate_srv.erl

@@ -1,12 +1,9 @@
 % vim: ts=4 sw=4 et
-% Copyright (c) 2013-2015 Jesse Gumm
+% Copyright (c) 2013-2021 Jesse Gumm
 % See LICENSE for licensing information.
-%
-% NOTE: You'll probably notice that this isn't *actually* a server.  It *used*
-% to be a server, but is now instead just where we interact with the qdate
-% application environment.  Anyway, sorry for the confusion.
 
 -module(qdate_srv).
+-behaviour(gen_server).
 
 -export([
     set_timezone/1,
@@ -28,6 +25,19 @@
     get_formats/0
 ]).
 
+
+%% API
+-export([start_link/0]).
+
+%% gen_server callbacks
+-export([init/1,
+         handle_call/3,
+         handle_cast/2,
+         handle_info/2,
+         terminate/2,
+         code_change/3]).
+
+
 %% Simple wrappers for unique keys
 -define(BASETAG, qdate_var).
 -define(KEY(Name), {?BASETAG, Name}).
@@ -39,6 +49,42 @@
 -define(FORMATTAG, qdate_format).
 -define(FORMATKEY(Name), {?FORMATTAG, Name}).
 
+-define(SERVER, ?MODULE).
+-define(TABLE, ?MODULE).
+
+-record(state, {}).
+
+start_link() ->
+    gen_server:start_link({local, ?SERVER}, ?MODULE, [], []).
+
+init([]) ->
+    error_logger:info_msg("Creating qdate ETS Table: ~p",[?TABLE]),
+    ?TABLE = ets:new(?TABLE, [public, {read_concurrency, true}, named_table]),
+    {ok, #state{}}.
+
+handle_call({set, Key, Val}, _From, State) ->
+    ets:insert(?TABLE, {Key, Val}),
+    {reply, ok, State};
+handle_call({unset, Key}, _From, State) ->
+    ets:delete(?TABLE, Key),
+    {reply, ok, State};
+handle_call(_, _From, State) ->
+    {reply, invalid_request, State}.
+
+handle_cast(_Msg, State) ->
+        {noreply, State}.
+
+handle_info(_Info, State) ->
+        {noreply, State}.
+
+terminate(_Reason, _State) ->
+        ok.
+
+code_change(_OldVsn, State, _Extra) ->
+        {ok, State}.
+
+
+
 %% PUBLIC API FUNCTIONS
 
 set_timezone(TZ) ->
@@ -91,26 +137,41 @@ get_formats() ->
 %% App Vars
 
 set_env(Key, Val) ->
-    application:set_env(qdate, ?KEY(Key), Val).
+    gen_server:call(?SERVER, {set, ?KEY(Key), Val}).
 
 get_env(Key) ->
     get_env(Key, undefined).
 
 get_env(Key, Default) ->
-    %% Soon, this can just be replaced with application:get_env/3
+    case ets:lookup(?TABLE, ?KEY(Key)) of
-    %% which was introduced in R16B.
+        [{__Key, Val}] -> Val;
-    case application:get_env(qdate, ?KEY(Key)) of
+        [] -> Default
-        undefined -> Default;
-        {ok, Val} -> Val
     end.
 
 unset_env(Key) ->
-    application:unset_env(qdate, ?KEY(Key)).
+    gen_server:call(?SERVER, {unset, ?KEY(Key)}).
 
 get_all_env(FilterTag) ->
-    All = application:get_all_env(qdate),
+    try ets:tab2list(?TABLE) of
-    %% Maybe this is a little nasty.
+        All ->
-    [{Key, V} || {{?BASETAG, {Tag, Key}}, V} <- All, Tag==FilterTag].
+            [{Key, V} || {{?BASETAG, {Tag, Key}}, V} <- All, Tag==FilterTag]
+    catch
+        error:badarg:S ->
+            Msg = maybe_start_msg(),
+            logger:error(Msg),
+          
+            error({qdate_get_all_env_failed, #{
+                original_error => {error, badarg, S}
+            }})
+    end.
+
+maybe_start_msg() ->
+    "Attempting to read qdate environment failed (qdate_srv:get_all_env/1).\n"
+    "qdate may not have been started properly.\n"
+    "Please ensure qdate is started properly by either:\n"
+    "* Putting qdate in the 'applications' key in your .app.src or .app file, or\n"
+    "* Starting it manually with application:ensure_all_started(qdate) or qdate:start().".
+
 
 %% ProcDic Vars
 
@@ -123,3 +184,9 @@ put_pd(Key, Val) ->
 
 unset_pd(Key) ->
     put_pd(Key, undefined).
+
+
+
+
+
+

src/qdate_sup.erl

@@ -0,0 +1,32 @@
+-module(qdate_sup).
+
+-behaviour(supervisor).
+
+%% API
+-export([start_link/0]).
+
+%% Supervisor callbacks
+-export([init/1]).
+
+-define(SERVER, ?MODULE).
+
+start_link() ->
+        supervisor:start_link({local, ?SERVER}, ?MODULE, []).
+
+init([]) ->
+
+        SupFlags = #{},
+
+        ChildSpec = #{
+            id=>qdate_srv,
+            start=>{qdate_srv, start_link, []}
+        },
+
+        {ok, {SupFlags, [ChildSpec]}}.
+
+%%%===================================================================
+%%% Internal functions
+%%%===================================================================
+
+
+