add gs

RCCService2018/content/LuaPackages/OtterImpl/instant.spec.lua

@@ -0,0 +1,39 @@
+return function()
+	local instant = require(script.Parent.instant)
+
+	it("should have the expected APIs", function()
+		local goal = instant(5)
+
+		expect(goal).to.be.a("table")
+		expect(goal.step).to.be.a("function")
+	end)
+
+	it("should immediately complete", function()
+		local state = {
+			value = 5,
+			complete = false,
+		}
+
+		local goal = instant(10)
+		state = goal:step(state, 1e-3)
+
+		expect(state.value).to.equal(10)
+		expect(state.complete).to.equal(true)
+	end)
+
+	it("should remove extra values from state", function()
+		local state = {
+			value = 5,
+			complete = false,
+
+			velocity = 7,
+			somethingElse = {},
+		}
+
+		local goal = instant(10)
+		state = goal:step(state, 1e-3)
+
+		expect(state.velocity).to.never.be.ok()
+		expect(state.somethingElse).to.never.be.ok()
+	end)
+end