Add unit test for Font roblox datatype

tests/roblox/datatypes/Font.luau

@@ -0,0 +1,54 @@
+-- HACK: Make luau happy, with the mlua rust
+-- crate all globals are also present in _G
+local Enum = _G.Enum
+local Font = _G.Font
+
+-- Constructors
+
+Font.new("")
+Font.new("", Enum.FontWeight.Bold)
+Font.new("", Enum.FontWeight.Bold, Enum.FontStyle.Italic)
+
+assert(not pcall(function()
+	Font.new("", Enum.FontStyle.Italic, Enum.FontWeight.Bold)
+end))
+assert(not pcall(function()
+	return Font.new()
+end))
+assert(not pcall(function()
+	return Font.new(false)
+end))
+assert(not pcall(function()
+	return Font.new("", "")
+end))
+assert(not pcall(function()
+	return Font.new(newproxy(true))
+end))
+
+Font.fromEnum(Enum.Font.Gotham)
+Font.fromEnum(Enum.Font.GothamMedium)
+Font.fromEnum(Enum.Font.GothamBold)
+
+Font.fromName("file-name")
+Font.fromName("file-name", Enum.FontWeight.Bold)
+Font.fromName("file-name", Enum.FontWeight.Bold, Enum.FontStyle.Italic)
+
+Font.fromId(1234567890)
+Font.fromId(1234567890, Enum.FontWeight.Bold)
+Font.fromId(1234567890, Enum.FontWeight.Bold, Enum.FontStyle.Italic)
+
+-- Properties
+
+local arial = "rbxasset://fonts/families/Arial.json"
+assert(Font.new(arial).Family == arial)
+assert(Font.fromName("Arial").Family == arial)
+assert(Font.fromEnum(Enum.Font.Arial).Family == arial)
+assert(Font.fromId(1234567890).Family == "rbxassetid://1234567890")
+
+for _, weight in Enum.FontWeight:GetEnumItems() do
+	assert(Font.new(arial, weight).Weight == weight)
+end
+
+for _, style in Enum.FontStyle:GetEnumItems() do
+	assert(Font.new(arial, Enum.FontWeight.Regular, style).Style == style)
+end