Add tests and build scripts.

[string-lerp.git] / tests / string-lerp.js

diff --git a/tests/string-lerp.js b/tests/string-lerp.js
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+++ b/tests/string-lerp.js
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+var JS = this.JS || require('jstest');
+var m = require('../string-lerp');
+
+JS.Test.describe('fast lerp', function () { with (this) {
+    var lerp = m.fastLerp;
+    var A = "Do you like green eggs and ham?";
+    var B = "I do not like them, Sam-I-am.";
+
+    it("handles empty strings", function () { with (this) {
+        assertEqual("", lerp("", "", -1));
+        assertEqual("", lerp("", "", 0));
+        assertEqual("", lerp("", "", 0.5));
+        assertEqual("", lerp("", "", 1));
+        assertEqual("", lerp("", "", 2));
+    }});
+
+    it("maintains identity", function () { with (this) {
+        for (var i = -1; i < 2; i += 1/1024) {
+            assertEqual(A, lerp(A, A, i));
+            assertEqual(B, lerp(B, B, i));
+        }
+    }});
+
+    it("handles lows", function () { with (this) {
+        assertEqual(A, lerp(A, B, -Infinity));
+        assertEqual(A, lerp(A, B, -1));
+        assertEqual(A, lerp(A, B, 0));
+    }});
+
+    it("handles highs", function () { with (this) {
+        assertEqual(B, lerp(A, B, 1));
+        assertEqual(B, lerp(A, B, 2));
+        assertEqual(B, lerp(A, B, Infinity));
+    }});
+
+    it("crams strings together", function () { with (this) {
+        assertEqual("I do not ke green eggs and ham?", lerp(A, B, 0.3));
+        assertEqual("I do not like tn eggs and ham?", lerp(A, B, 0.5));
+        assertEqual("I do not like them, Sam-I-am?", lerp(A, B, 0.98));
+    }});
+}});
+
+JS.Test.describe('diff lerp', function () { with (this) {
+    var lerp = m.diffLerp;
+    var A = "Do you like green eggs and ham?";
+    var B = "I do not like them, Sam-I-am.";
+
+    it("handles empty strings", function () { with (this) {
+        assertEqual("", lerp("", "", -1));
+        assertEqual("", lerp("", "", 0));
+        assertEqual("", lerp("", "", 0.5));
+        assertEqual("", lerp("", "", 1));
+        assertEqual("", lerp("", "", 2));
+    }});
+
+    it("maintains identity", function () { with (this) {
+        for (var i = -1; i < 2; i += 1/1024) {
+            assertEqual(A, lerp(A, A, i));
+            assertEqual(B, lerp(B, B, i));
+        }
+    }});
+
+    it("handles lows", function () { with (this) {
+        assertEqual(A, lerp(A, B, -Infinity));
+        assertEqual(A, lerp(A, B, -1));
+        assertEqual(A, lerp(A, B, 0));
+    }});
+
+    it("handles highs", function () { with (this) {
+        assertEqual(B, lerp(A, B, 1));
+        assertEqual(B, lerp(A, B, 2));
+        assertEqual(B, lerp(A, B, Infinity));
+    }});
+
+    it("edits strings", function () { with (this) {
+        assertEqual("Do you like green eggsSam-I-am.", lerp(A, B, 0.3));
+        assertEqual("Do you like green Sam-I-am.", lerp(A, B, 0.5));
+        assertEqual("do not like them, Sam-I-am.", lerp(A, B, 0.9));
+    }});
+}});
+
+JS.Test.describe('numeric lerp', function () { with (this) {
+    var lerp = m.numericLerp;
+
+    it("handles empty strings", function () { with (this) {
+        assertEqual("", lerp("", "", -1));
+        assertEqual("", lerp("", "", 0));
+        assertEqual("", lerp("", "", 0.5));
+        assertEqual("", lerp("", "", 1));
+        assertEqual("", lerp("", "", 2));
+    }});
+
+    it("handles single numbers", function () { with (this) {
+        assertEqual("0", lerp("0", "100", 0));
+        assertEqual("50", lerp("0", "100", 0.5));
+        assertEqual("100", lerp("0", "100", 1.0));
+        assertEqual("150", lerp("0", "100", 1.5));
+    }});
+
+    it("rounds integers", function () { with (this) {
+        assertEqual("12", lerp("0", "100", 0.123));
+        assertEqual("12.3", lerp("0", "100.0", 0.123));
+        assertEqual("12.3", lerp("0.0", "100", 0.123));
+        assertEqual("12.3", lerp("0.0", "100.0", 0.123));
+    }});
+
+    it("computes parameters outside [0, 1]", function () { with (this) {
+        assertEqual("Giving 110%", lerp("Giving 0%", "Giving 100%", 1.1));
+    }});
+
+    it("handles multiple numbers", function () { with (this) {
+        var A = "Chapter 0. The sky was rgb(0, 0, 0)."
+        var B = "Chapter 10. The sky was rgb(0, 0, 255)."
+        assertEqual(A, lerp(A, B, 0));
+        assertEqual(B, lerp(A, B, 1));
+        assertEqual("Chapter 5. The sky was rgb(0, 0, 128).", lerp(A, B, 0.5));
+    }});
+}});