Throw error if value of samples is not valid. Solves issue #8

package.json

@@ -1,7 +1,7 @@
 {
   "private": false,
   "name": "curve-interpolator",
-  "version": "2.0.7",
+  "version": "2.0.8",
   "description": "Interpolate values on a Cardinal/Catmull-Rom spline curve",
   "repository": "https://github.com/kjerandp/curve-interpolator",
   "bugs": {

src/curve-interpolator.ts

@@ -137,9 +137,11 @@ export default class CurveInterpolator {
   getPoints<T extends VectorType>(samples:number, returnType: { new() : T }) : T[]
   getPoints<T extends VectorType>(samples:number, returnType: { new() : T }, from:number) : T[]
   getPoints<T extends VectorType>(samples:number, returnType: { new() : T }, from:number, to:number) : T[]
+  getPoints()
   getPoints(samples:number)
   getPoints(samples:number, returnType: null, from:number, to:number) : Vector[]
   getPoints(samples:number = 100, returnType?: { new() : VectorType }, from:number = 0, to:number = 1) : Vector[] {
+    if (!samples || samples <= 0) throw Error('Invalid arguments passed to getPoints(). You must specify at least 1 sample/segment.')
     if (from < 0 || to > 1 || to < from) return undefined;
 
     const pts = [];

test/curve-interpolator.spec.ts

@@ -63,6 +63,9 @@ describe('curve-interpolator.ts', () => {
     expect(result[result.length - 1].x).to.eq(points[points.length - 1][0]);
     expect(result[result.length - 1].y).to.eq(points[points.length - 1][1]);
     result.every(r => expect(r).to.be.instanceof(Point));
+
+    expect(() => interp.getPoints(0)).to.throw();
+    expect(() => interp.getPoints()).not.to.throw();
   });
 
   it('should be able to lookup values on curve', () => {