import { point, pointRotateRads } from "./point"; import type { Radians } from "./types"; describe("rotate", () => { it("should rotate over (x2, y2) and return the rotated coordinates for (x1, y1)", () => { const x1 = 10; const y1 = 20; const x2 = 20; const y2 = 30; const angle = (Math.PI / 2) as Radians; const [rotatedX, rotatedY] = pointRotateRads( point(x1, y1), point(x2, y2), angle, ); expect([rotatedX, rotatedY]).toEqual([30, 20]); const res2 = pointRotateRads( point(rotatedX, rotatedY), point(x2, y2), -angle as Radians, ); expect(res2).toEqual([x1, x2]); }); });