tests/string-lerp.js

   1 var JS = this.JS || require('jstest');
   2 var m = require('../string-lerp');
   3
   4 JS.Test.describe('fast lerp', function () { with (this) {
   5     var lerp = m.fastLerp;
   6     var A = "Do you like green eggs and ham?";
   7     var B = "I do not like them, Sam-I-am.";
   8
   9     it("handles empty strings", function () { with (this) {
  10         assertEqual("", lerp("", "", -1));
  11         assertEqual("", lerp("", "", 0));
  12         assertEqual("", lerp("", "", 0.5));
  13         assertEqual("", lerp("", "", 1));
  14         assertEqual("", lerp("", "", 2));
  15     }});
  16
  17     it("maintains identity", function () { with (this) {
  18         for (var i = -1; i < 2; i += 1/1024) {
  19             assertEqual(A, lerp(A, A, i));
  20             assertEqual(B, lerp(B, B, i));
  21         }
  22     }});
  23
  24     it("handles lows", function () { with (this) {
  25         assertEqual(A, lerp(A, B, -Infinity));
  26         assertEqual(A, lerp(A, B, -1));
  27         assertEqual(A, lerp(A, B, 0));
  28     }});
  29
  30     it("handles highs", function () { with (this) {
  31         assertEqual(B, lerp(A, B, 1));
  32         assertEqual(B, lerp(A, B, 2));
  33         assertEqual(B, lerp(A, B, Infinity));
  34     }});
  35
  36     it("crams strings together", function () { with (this) {
  37         assertEqual("I do not ke green eggs and ham?", lerp(A, B, 0.3));
  38         assertEqual("I do not like tn eggs and ham?", lerp(A, B, 0.5));
  39         assertEqual("I do not like them, Sam-I-am?", lerp(A, B, 0.98));
  40     }});
  41 }});
  42
  43 JS.Test.describe('diff lerp', function () { with (this) {
  44     var lerp = m.diffLerp;
  45     var A = "Do you like green eggs and ham?";
  46     var B = "I do not like them, Sam-I-am.";
  47
  48     it("handles empty strings", function () { with (this) {
  49         assertEqual("", lerp("", "", -1));
  50         assertEqual("", lerp("", "", 0));
  51         assertEqual("", lerp("", "", 0.5));
  52         assertEqual("", lerp("", "", 1));
  53         assertEqual("", lerp("", "", 2));
  54     }});
  55
  56     it("maintains identity", function () { with (this) {
  57         for (var i = -1; i < 2; i += 1/1024) {
  58             assertEqual(A, lerp(A, A, i));
  59             assertEqual(B, lerp(B, B, i));
  60         }
  61     }});
  62
  63     it("handles lows", function () { with (this) {
  64         assertEqual(A, lerp(A, B, -Infinity));
  65         assertEqual(A, lerp(A, B, -1));
  66         assertEqual(A, lerp(A, B, 0));
  67     }});
  68
  69     it("handles highs", function () { with (this) {
  70         assertEqual(B, lerp(A, B, 1));
  71         assertEqual(B, lerp(A, B, 2));
  72         assertEqual(B, lerp(A, B, Infinity));
  73     }});
  74
  75     it("edits strings", function () { with (this) {
  76         assertEqual("Do you like green eggsSam-I-am.", lerp(A, B, 0.3));
  77         assertEqual("Do you like green Sam-I-am.", lerp(A, B, 0.5));
  78         assertEqual("do not like them, Sam-I-am.", lerp(A, B, 0.9));
  79     }});
  80 }});
  81
  82 JS.Test.describe('numeric lerp', function () { with (this) {
  83     var lerp = m.numericLerp;
  84
  85     it("handles empty strings", function () { with (this) {
  86         assertEqual("", lerp("", "", -1));
  87         assertEqual("", lerp("", "", 0));
  88         assertEqual("", lerp("", "", 0.5));
  89         assertEqual("", lerp("", "", 1));
  90         assertEqual("", lerp("", "", 2));
  91     }});
  92
  93     it("handles single numbers", function () { with (this) {
  94         assertEqual("0", lerp("0", "100", 0));
  95         assertEqual("50", lerp("0", "100", 0.5));
  96         assertEqual("100", lerp("0", "100", 1.0));
  97         assertEqual("150", lerp("0", "100", 1.5));
  98     }});
  99
 100     it("rounds integers", function () { with (this) {
 101         assertEqual("12", lerp("0", "100", 0.123));
 102         assertEqual("12.3", lerp("0", "100.0", 0.123));
 103         assertEqual("12.3", lerp("0.0", "100", 0.123));
 104         assertEqual("12.3", lerp("0.0", "100.0", 0.123));
 105     }});
 106
 107     it("computes parameters outside [0, 1]", function () { with (this) {
 108         assertEqual("Giving 110%", lerp("Giving 0%", "Giving 100%", 1.1));
 109     }});
 110
 111     it("handles multiple numbers", function () { with (this) {
 112         var A = "Chapter 0. The sky was rgb(0, 0, 0)."
 113         var B = "Chapter 10. The sky was rgb(0, 0, 255)."
 114         assertEqual(A, lerp(A, B, 0));
 115         assertEqual(B, lerp(A, B, 1));
 116         assertEqual("Chapter 5. The sky was rgb(0, 0, 128).", lerp(A, B, 0.5));
 117     }});
 118 }});