Added more unit tests.

dist/d3-interpolate-curve.js

@@ -1,27 +1,27 @@
-// https://github.com/jamesleesaunders/ v1.0.1 Copyright 2019 James Saunders
+// https://github.com/jamesleesaunders/ v1.0.2 Copyright 2019 James Saunders
 (function (global, factory) {
-typeof exports === 'object' && typeof module !== 'undefined' ? factory(exports, require('d3-shape'), require('d3-array')) :
-typeof define === 'function' && define.amd ? define(['exports', 'd3-shape', 'd3-array'], factory) :
-(factory((global.d3 = global.d3 || {}),global.d3,global.d3));
-}(this, (function (exports,d3Shape,d3Array) { 'use strict';
+typeof exports === 'object' && typeof module !== 'undefined' ? factory(exports, require('d3-shape'), require('d3-array'), require('d3-interpolate')) :
+typeof define === 'function' && define.amd ? define(['exports', 'd3-shape', 'd3-array', 'd3-interpolate'], factory) :
+(factory((global.d3 = global.d3 || {}),global.d3,global.d3,global.d3));
+}(this, (function (exports,d3Shape,d3Array,d3Interpolate) { 'use strict';
 
 /**
  * Curve Polator
  *
  * @param points
- * @param curve
+ * @param curveFunction
  * @param epsilon
  * @param samples
  * @returns {Function}
  */
-function curvePolator(points, curve, epsilon, samples) { // eslint-disable-line max-params
-  const path = d3Shape.line().curve(curve)(points);
+function curvePolator(points, curveFunction, epsilon, samples) { // eslint-disable-line max-params
+  const path = d3Shape.line().curve(curveFunction)(points);
 
   return svgPathInterpolator(path, epsilon, samples);
 }
 
 /**
- * SVG Psth Interpolator
+ * SVG Path Interpolator
  *
  * @param path
  * @param epsilon
@@ -87,17 +87,22 @@ function svgPathInterpolator(path, epsilon, samples) {
  * Interpolate From Curve
  *
  * @param values
- * @param curve
+ * @param curveFunction
  * @param epsilon
  * @param samples
  * @returns {Function}
  */
-function fromCurve(values, curve, epsilon = 0.00001, samples = 100) { // eslint-disable-line max-params
+function fromCurve(values, curveFunction, epsilon = 0.00001, samples = 100) { // eslint-disable-line max-params
   const length = values.length;
   const xrange = d3Array.range(length).map(function(d, i) { return i * (1 / (length - 1)); });
   const points = values.map((v, i) => [xrange[i], v]);
 
-  return curvePolator(points, curve, epsilon, samples);
+  // If curveFunction is curveBasis then reach straight for D3's native 'interpolateBasis' function (it's faster!)
+  if (curveFunction === d3Shape.curveBasis) {
+    return d3Interpolate.interpolateBasis(values);
+  } else {
+    return curvePolator(points, curveFunction, epsilon, samples);
+  }
 }
 
 /**