add gs

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

@@ -0,0 +1,144 @@
+return function()
+	local spring = require(script.Parent.spring)
+
+	it("should have all expected APIs", function()
+		expect(spring).to.be.a("function")
+
+		local s = spring(1, {
+			dampingRatio = 0.1,
+			frequency = 10,
+		})
+
+		expect(s).to.be.a("table")
+		expect(s.step).to.be.a("function")
+
+		-- handle when spring lacks option table
+		s = spring(1)
+
+		expect(s).to.be.a("table")
+		expect(s.step).to.be.a("function")
+	end)
+
+	it("should handle being still correctly", function()
+		local s = spring(1, {
+			dampingRatio = 0.1,
+			frequency = 10,
+		})
+
+		local state = s:step({
+			value = 1,
+			velocity = 0,
+			complete = false,
+		}, 1)
+
+		expect(state.value).to.equal(1)
+		expect(state.velocity).to.equal(0)
+		expect(state.complete).to.equal(true)
+	end)
+
+	it("should return not complete when in motion", function()
+		local goal = spring(100, {
+			dampingRatio = 0.1,
+			frequency = 10,
+		})
+
+		local state = {
+			value = 1,
+			velocity = 0,
+			complete = false,
+		}
+
+		state = goal:step(state, 1e-3)
+
+		expect(state.value < 100).to.equal(true)
+		expect(state.velocity > 0).to.equal(true)
+		expect(state.complete).to.equal(false)
+	end)
+
+	describe("should eventaully complete when", function()
+		it("is critically damped", function()
+			local s = spring(3, {
+				dampingRatio = 1,
+				frequency = 0.5,
+			})
+
+			local state = {
+				value = 1,
+				velocity = 0,
+				complete = false,
+			}
+
+			while not state.complete do
+				state = s:step(state, 0.5)
+			end
+
+			expect(state.complete).to.equal(true)
+			expect(state.value).to.equal(3)
+			expect(state.velocity).to.equal(0)
+		end)
+
+		it("is over damped", function()
+			local s = spring(3, {
+				dampingRatio = 10,
+				frequency = 0.5,
+			})
+
+			local state = {
+				value = 1,
+				velocity = 0,
+				complete = false,
+			}
+
+			while not state.complete do
+				state = s:step(state, 0.5)
+			end
+
+			expect(state.complete).to.equal(true)
+			expect(state.value).to.equal(3)
+			expect(state.velocity).to.equal(0)
+		end)
+
+		it("is under damped", function()
+			local s = spring(3, {
+				dampingRatio = 0.1,
+				frequency = 0.5,
+			})
+
+			local state = {
+				value = 1,
+				velocity = 0,
+				complete = false,
+			}
+
+			while not state.complete do
+				state = s:step(state, 0.5)
+			end
+
+			expect(state.complete).to.equal(true)
+			expect(state.value).to.equal(3)
+			expect(state.velocity).to.equal(0)
+		end)
+	end)
+
+	it("should remain complete when completed", function()
+		local s = spring(3, {
+			dampingRatio = 1,
+			frequency = 0.5,
+		})
+
+		local state = {
+			value = 1,
+			velocity = 0,
+			complete = false,
+		}
+
+		while not state.complete do
+			state = s:step(state, 0.5)
+		end
+		state = s:step(state, 0.5)
+
+		expect(state.complete).to.equal(true)
+		expect(state.value).to.equal(3)
+		expect(state.velocity).to.equal(0)
+	end)
+end