WoWUnit.lua

local Enabled, Events, Replaces = true, {}, {}
local NIL = {}


--[[ Registry ]]--

function WoWUnit:NewGroup(name, ...)
	if not self:HasGroup(name) then
		local group = self.Group:New(name)
		tinsert(self.children, group)

		if ... then
			for i = 1, select('#', ...) do
				self:AddToEvent(group, select(i, ...))
			end
		else
			self:AddToEvent(group, 'PLAYER_LOGIN')
		end

		return group
	end
end

function WoWUnit:HasGroup(name)
	return FindInTableIf(self.children, function(g) return g.name == name end)
end

function WoWUnit:AddToEvent(group, event)
	self:RegisterEvent(event)
	Events[event] = Events[event] or {}
	tinsert(Events[event], group)
end

function WoWUnit:RunTests(event)
	for _, group in ipairs(Events[event]) do
		group()
	end
end


--[[ Mocking ]]--

local function Store(value)
	return value == nil and NIL or value
end

local function Extract(value)
	if value ~= NIL then
		return value
	end
end

function WoWUnit.Replace(table, key, replace)
	if replace == nil then
		table, key, replace = _G, table, key
	end

	Replaces[table] = Replaces[table] or {}
	Replaces[table][key] = Replaces[table][key] or Store(table[key])

	table[key] = replace
end

function WoWUnit.ClearReplaces()
	for table, keys in pairs(Replaces) do
		for key, original in pairs(keys) do
			table[key] = Extract(original)
		end
	end

	wipe(Replaces)
end


--[[ Control ]]--

function WoWUnit.Enable()
	Enabled = true
end

function WoWUnit.Disable()
	Enabled = false
end

function WoWUnit.Enabled()
	return Enabled
end


--[[ Assertions ]]--

local function Raise(message)
	error('|n|n' .. HIGHLIGHT_FONT_COLOR_CODE .. message .. FONT_COLOR_CODE_CLOSE, 3)
end

local function IsTable(value)
	return type(value) == 'table'
end

local function Difference(a, b)
	if IsTable(a) and IsTable(b) then
		for key, value in pairs(a) do
			local path, a, b = Difference(value, b[key])
			if path then
				return "." .. key .. path, a, b
			end
		end

		for key, value in pairs(b) do
			if a[key] == nil then
				return "." .. key, nil, value
			end
		end

	elseif a ~= b then
		return "", a, b
	end
end

function WoWUnit.AreEqual(a, b)
	local path, a, b = Difference(a, b)
	if path then
		local message = format('Expected %s|nGot %s', tostring(a), tostring(b))
		if path ~= "" then
			message = format('Tables differ at "%s"|n', path:sub(2)) .. message
		end

		Raise(message)
	end
end

function WoWUnit.IsTrue(value)
	if not value then
		Raise(format('Expected some value, got %s', tostring(value)))
	end
end

function WoWUnit.IsFalse(value)
	if value then
		Raise(format('Expected no value, got %s', tostring(value)))
	end
end


WoWUnit.__index = getmetatable(WoWUnit).__index
WoWUnit.__call = WoWUnit.NewGroup
WoWUnit.Exists = WoWUnit.IsTrue
WoWUnit.children = {}
setmetatable(WoWUnit, WoWUnit)