Add conditionally-enabled typechecking using t

plugin/src/Types.lua

@@ -0,0 +1,36 @@
+local t = require(script.Parent.Parent.t)
+
+local DevSettings = require(script.Parent.DevSettings)
+
+local VirtualValue = t.interface({
+	Type = t.string,
+	Value = t.optional(t.any),
+})
+
+local VirtualMetadata = t.interface({
+	ignoreUnknownInstances = t.optional(t.boolean),
+})
+
+local VirtualInstance = t.interface({
+	Name = t.string,
+	ClassName = t.string,
+	Properties = t.map(t.string, VirtualValue),
+	Metadata = t.optional(VirtualMetadata)
+})
+
+local function ifEnabled(innerCheck)
+	return function(...)
+		if DevSettings:shouldTypecheck() then
+			return innerCheck(...)
+		else
+			return true
+		end
+	end
+end
+
+return {
+	ifEnabled = ifEnabled,
+	VirtualInstance = VirtualInstance,
+	VirtualMetadata = VirtualMetadata,
+	VirtualValue = VirtualValue,
+}