--
-- Tests for the `version` module
--
local Version = require 'Version'
local tasty = require 'tasty'

local group = tasty.test_group
local test = tasty.test_case
local assert = tasty.assert

return {
  group 'constructor' {
    test('has type `userdata`', function ()
      assert.are_same(type(Version {2}), 'userdata')
    end),
    test('accepts list of integers', function ()
      assert.are_same(type(Version {2, 7, 3}), 'userdata')
    end),
    test('accepts a single integer', function ()
      assert.are_same(Version(5), Version {5})
    end),
    test('accepts version as string', function ()
      assert.are_same(
        Version '4.45.1',
        Version {4, 45, 1}
      )
    end),
    test('non-version string is rejected', function ()
      local success, msg = pcall(function () return Version '11friends' end)
      assert.is_falsy(success)
      assert.is_truthy(tostring(msg):match('11friends'))
    end)
  },

  group 'comparison' {
    test('smaller (equal) than', function ()
      assert.is_truthy(Version {2, 58, 3} < Version {2, 58, 4})
      assert.is_falsy(Version {2, 60, 1} < Version {2, 59, 2})
      assert.is_truthy(Version {0, 14, 3} < Version {0, 14, 3, 1})
      assert.is_truthy(Version {3, 58, 3} <= Version {4})
      assert.is_truthy(Version {0, 14, 3} <= Version {0, 14, 3, 1})
    end),
    test('larger (equal) than', function ()
      assert.is_truthy(Version{2,58,3} > Version {2, 57, 4})
      assert.is_truthy(Version{2,58,3} > Version {2, 58, 2})
      assert.is_truthy(Version {0, 8} >= Version {0, 8})
      assert.is_falsy(Version {0, 8} >= Version {0, 8, 2})
    end),
    test('equality', function ()
      assert.is_truthy(Version '8.8', Version {8, 8})
    end),
    test('second argument can be a version string', function ()
      assert.is_truthy(Version '8' < '9.1')
      assert.is_falsy(Version '8.8' < '8.7')
    end),
    test('equality test works with value not usable as a version', function ()
      assert.is_falsy(Version '8' == function() end)
    end),
    test('other comparisons fail if one value is not a version', function ()
      assert.error_matches(
        function () return Version '8' < (function() end) end,
        'could not peek Version'
      )
      assert.error_matches(
        function () return Version '8' <= (function() end) end,
        'could not peek Version'
      )
      assert.error_matches(
        function () return Version '8' > (function() end) end,
        'could not peek Version'
      )
    end)
  },

  group 'conversion to string' {
    test('converting from and to string is a noop', function ()
      local version_string = '1.19.4'
      assert.are_equal(tostring(Version(version_string)), version_string)
    end)
  },

  group 'convenience functions' {
    test('throws error if version is too old', function ()
      local actual = Version {2, 8}
      local expected = Version {2, 9}
      assert.error_matches(
        function () actual:must_be_at_least(expected) end,
        'expected version 2.9 or newer, got 2.8'
      )
    end),
    test('does nothing if expected version is older than actual', function ()
      local actual = Version '2.9'
      local expected = Version '2.8'
      actual:must_be_at_least(expected)
    end),
    test('does nothing if expected version equals to actual', function ()
      local actual = Version '2.8'
      local expected = Version '2.8'
      actual:must_be_at_least(expected)
    end)
  },

  group 'list-like behavior' {
    test('can access version component numbers', function ()
      local version = Version '2.7.3'
      assert.is_nil(version[0])
      assert.are_equal(version[1], 2)
      assert.are_equal(version[2], 7)
      assert.are_equal(version[3], 3)
    end),
    test('can be iterated over', function ()
      local version_list = {2, 7, 3}
      local final_index = 0
      for i, v in pairs(Version(version_list)) do
        assert.are_equal(v, version_list[i])
        final_index = i
      end
      assert.are_equal(final_index, 3)
    end),
    test('length is the number of components', function ()
      assert.are_equal(#(Version '0'), 1)
      assert.are_equal(#(Version '1.6'), 2)
      assert.are_equal(#(Version '8.7.5'), 3)
      assert.are_equal(#(Version '2.9.1.5'), 4)
    end),
    test('branches can be modified', function ()
      local v = Version '5.3.6'
      v[2] = 2
      v[3] = nil
      assert.are_equal(v, Version '5.2')
    end)
  }
}