Exercism: Leap

erlang/leap/.exercism/config.json

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+{
+  "blurb": "Given a year, report if it is a leap year.",
+  "authors": [
+    "tmcgilchrist"
+  ],
+  "contributors": [
+    "ErikSchierboom",
+    "iHiD",
+    "JordanAdams",
+    "juhlig",
+    "kytrinyx",
+    "NobbZ",
+    "xymbol"
+  ],
+  "files": {
+    "solution": [
+      "src/leap.erl"
+    ],
+    "test": [
+      "test/leap_tests.erl"
+    ],
+    "example": [
+      ".meta/example.erl"
+    ]
+  },
+  "source": "JavaRanch Cattle Drive, exercise 3",
+  "source_url": "http://www.javaranch.com/leap.jsp"
+}

erlang/leap/.exercism/metadata.json

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+{"track":"erlang","exercise":"leap","id":"a86123e823824d97855ac299e3fb2b10","url":"https://exercism.org/tracks/erlang/exercises/leap","handle":"JBiason","is_requester":true,"auto_approve":false}

erlang/leap/HELP.md

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+# Help
+
+## Running the tests
+
+You can run the tests by running the following command from the exercise directory.
+
+```bash
+$ rebar3 eunit
+```
+
+## Submitting your solution
+
+You can submit your solution using the `exercism submit src/leap.erl` command.
+This command will upload your solution to the Exercism website and print the solution page's URL.
+
+It's possible to submit an incomplete solution which allows you to:
+
+- See how others have completed the exercise
+- Request help from a mentor
+
+## Need to get help?
+
+If you'd like help solving the exercise, check the following pages:
+
+- The [Erlang track's documentation](https://exercism.org/docs/tracks/erlang)
+- [Exercism's support channel on gitter](https://gitter.im/exercism/support)
+- The [Frequently Asked Questions](https://exercism.org/docs/using/faqs)
+
+Should those resources not suffice, you could submit your (incomplete) solution to request mentoring.
+
+To get help if you're having trouble, you can use one of the following resources:
+
+- [Exercism related BEAM support channel on gitter](https://gitter.im/exercism/xerlang)
+- [Erlang Documentation](http://www.erlang.org/doc.html)
+- [Learn You Some Erlang for Great Good](http://learnyousomeerlang.com)
+- [StackOverflow](http://stackoverflow.com/)

erlang/leap/README.md

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+# Leap
+
+Welcome to Leap on Exercism's Erlang Track.
+If you need help running the tests or submitting your code, check out `HELP.md`.
+
+## Instructions
+
+Given a year, report if it is a leap year.
+
+The tricky thing here is that a leap year in the Gregorian calendar occurs:
+
+```text
+on every year that is evenly divisible by 4
+  except every year that is evenly divisible by 100
+    unless the year is also evenly divisible by 400
+```
+
+For example, 1997 is not a leap year, but 1996 is.  1900 is not a leap
+year, but 2000 is.
+
+## Notes
+
+Though our exercise adopts some very simple rules, there is more to
+learn!
+
+For a delightful, four minute explanation of the whole leap year
+phenomenon, go watch [this youtube video][video].
+
+[video]: http://www.youtube.com/watch?v=xX96xng7sAE
+
+## Source
+
+### Created by
+
+- @tmcgilchrist
+
+### Contributed to by
+
+- @ErikSchierboom
+- @iHiD
+- @JordanAdams
+- @juhlig
+- @kytrinyx
+- @NobbZ
+- @xymbol
+
+### Based on
+
+JavaRanch Cattle Drive, exercise 3 - http://www.javaranch.com/leap.jsp

erlang/leap/rebar.config

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+%% Erlang compiler options
+{erl_opts, [debug_info, warnings_as_errors]}.
+
+{deps, [{erl_exercism, "0.1.2"}]}.
+
+{dialyzer, [
+  {warnings, [underspecs, no_return]},
+  {get_warnings, true},
+  {plt_apps, top_level_deps}, % top_level_deps | all_deps
+  {plt_extra_apps, []},
+  {plt_location, local}, % local | "/my/file/name"
+  {plt_prefix, "rebar3"},
+  {base_plt_apps, [stdlib, kernel, crypto]},
+  {base_plt_location, global}, % global | "/my/file/name"
+  {base_plt_prefix, "rebar3"}
+]}.
+
+%% eunit:test(Tests)
+{eunit_tests, []}.
+%% Options for eunit:test(Tests, Opts)
+{eunit_opts, [verbose]}.
+
+%% == xref ==
+
+{xref_warnings, true}.
+
+%% xref checks to run
+{xref_checks, [undefined_function_calls, undefined_functions,
+  locals_not_used, exports_not_used,
+  deprecated_function_calls, deprecated_functions]}.

erlang/leap/src/leap.app.src

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+{application, leap,
+  [{description, "exercism.io - leap"},
+    {vsn, "0.0.1"},
+    {modules, []},
+    {registered, []},
+    {applications, [kernel,
+      stdlib]},
+    {env, []}
+  ]}.

erlang/leap/src/leap.erl

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+-module(leap).
+
+-export([leap_year/1]).
+
+
+leap_year(Year) -> 
+	(Year rem 4 == 0)
+	and ((Year rem 100 /= 0)
+	     or (Year rem 400 == 0)).

erlang/leap/test/leap_tests.erl

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+%% Generated with 'testgen v0.2.0'
+%% Revision 1 of the exercises generator was used
+%% https://github.com/exercism/problem-specifications/raw/a2c75d2e71c6a2efa1ce3d756292cc89d811136c/exercises/leap/canonical-data.json
+%% This file is automatically generated from the exercises canonical data.
+
+-module(leap_tests).
+
+-include_lib("erl_exercism/include/exercism.hrl").
+-include_lib("eunit/include/eunit.hrl").
+
+
+
+
+'1_year_not_divisible_by_4_in_common_year_test_'() ->
+    {"year not divisible by 4 in common year",
+     ?_assertNot(leap:leap_year(2015))}.
+
+'2_year_divisible_by_2_not_divisible_by_4_in_common_year_test_'() ->
+    {"year divisible by 2, not divisible by "
+     "4 in common year",
+     ?_assertNot(leap:leap_year(1970))}.
+
+'3_year_divisible_by_4_not_divisible_by_100_in_leap_year_test_'() ->
+    {"year divisible by 4, not divisible by "
+     "100 in leap year",
+     ?_assert(leap:leap_year(1996))}.
+
+'4_year_divisible_by_4_and_5_is_still_a_leap_year_test_'() ->
+    {"year divisible by 4 and 5 is still a "
+     "leap year",
+     ?_assert(leap:leap_year(1960))}.
+
+'5_year_divisible_by_100_not_divisible_by_400_in_common_year_test_'() ->
+    {"year divisible by 100, not divisible "
+     "by 400 in common year",
+     ?_assertNot(leap:leap_year(2100))}.
+
+'6_year_divisible_by_100_but_not_by_3_is_still_not_a_leap_year_test_'() ->
+    {"year divisible by 100 but not by 3 is "
+     "still not a leap year",
+     ?_assertNot(leap:leap_year(1900))}.
+
+'7_year_divisible_by_400_is_leap_year_test_'() ->
+    {"year divisible by 400 is leap year",
+     ?_assert(leap:leap_year(2000))}.
+
+'8_year_divisible_by_400_but_not_by_125_is_still_a_leap_year_test_'() ->
+    {"year divisible by 400 but not by 125 "
+     "is still a leap year",
+     ?_assert(leap:leap_year(2400))}.
+
+'9_year_divisible_by_200_not_divisible_by_400_in_common_year_test_'() ->
+    {"year divisible by 200, not divisible "
+     "by 400 in common year",
+     ?_assertNot(leap:leap_year(1800))}.