diff --git a/test/unit/adapter.js b/test/unit/engine_adapter.js
similarity index 100%
rename from test/unit/adapter.js
rename to test/unit/engine_adapter.js
diff --git a/test/unit/blocks.js b/test/unit/engine_blocks.js
similarity index 100%
rename from test/unit/blocks.js
rename to test/unit/engine_blocks.js
diff --git a/test/unit/runtime.js b/test/unit/engine_runtime.js
similarity index 100%
rename from test/unit/runtime.js
rename to test/unit/engine_runtime.js
diff --git a/test/unit/sequencer.js b/test/unit/engine_sequencer.js
similarity index 100%
rename from test/unit/sequencer.js
rename to test/unit/engine_sequencer.js
diff --git a/test/unit/thread.js b/test/unit/engine_thread.js
similarity index 100%
rename from test/unit/thread.js
rename to test/unit/engine_thread.js
diff --git a/test/unit/clone.js b/test/unit/sprites_clone.js
similarity index 100%
rename from test/unit/clone.js
rename to test/unit/sprites_clone.js
diff --git a/test/unit/util_cast.js b/test/unit/util_cast.js
new file mode 100644
index 000000000..dac55f596
--- /dev/null
+++ b/test/unit/util_cast.js
@@ -0,0 +1,178 @@
+var test = require('tap').test;
+var cast = require('../../src/util/cast');
+
+test('toNumber', function (t) {
+ // Numeric
+ t.equal(cast.toNumber(0), 0);
+ t.equal(cast.toNumber(1), 1);
+ t.equal(cast.toNumber(3.14), 3.14);
+
+ // String
+ t.equal(cast.toNumber('0'), 0);
+ t.equal(cast.toNumber('1'), 1);
+ t.equal(cast.toNumber('3.14'), 3.14);
+ t.equal(cast.toNumber('0.1e10'), 1000000000);
+ t.equal(cast.toNumber('foobar'), 0);
+
+ // Boolean
+ t.equal(cast.toNumber(true), 1);
+ t.equal(cast.toNumber(false), 0);
+ t.equal(cast.toNumber('true'), 0);
+ t.equal(cast.toNumber('false'), 0);
+
+ // Undefined & object
+ t.equal(cast.toNumber(undefined), 0);
+ t.equal(cast.toNumber({}), 0);
+ t.end();
+});
+
+test('toBoolean', function (t) {
+ // Numeric
+ t.equal(cast.toBoolean(0), false);
+ t.equal(cast.toBoolean(1), true);
+ t.equal(cast.toBoolean(3.14), true);
+
+ // String
+ t.equal(cast.toBoolean('0'), false);
+ t.equal(cast.toBoolean('1'), true);
+ t.equal(cast.toBoolean('3.14'), true);
+ t.equal(cast.toBoolean('0.1e10'), true);
+ t.equal(cast.toBoolean('foobar'), true);
+
+ // Boolean
+ t.equal(cast.toBoolean(true), true);
+ t.equal(cast.toBoolean(false), false);
+
+ // Undefined & object
+ t.equal(cast.toBoolean(undefined), false);
+ t.equal(cast.toBoolean({}), true);
+ t.end();
+});
+
+test('toString', function (t) {
+ // Numeric
+ t.equal(cast.toString(0), '0');
+ t.equal(cast.toString(1), '1');
+ t.equal(cast.toString(3.14), '3.14');
+
+ // String
+ t.equal(cast.toString('0'), '0');
+ t.equal(cast.toString('1'), '1');
+ t.equal(cast.toString('3.14'), '3.14');
+ t.equal(cast.toString('0.1e10'), '0.1e10');
+ t.equal(cast.toString('foobar'), 'foobar');
+
+ // Boolean
+ t.equal(cast.toString(true), 'true');
+ t.equal(cast.toString(false), 'false');
+
+ // Undefined & object
+ t.equal(cast.toString(undefined), 'undefined');
+ t.equal(cast.toString({}), '[object Object]');
+ t.end();
+});
+
+test('toRbgColorList', function (t) {
+ // Hex (minimal, see "color" util tests)
+ t.deepEqual(cast.toRgbColorList('#000'), [0,0,0]);
+ t.deepEqual(cast.toRgbColorList('#000000'), [0,0,0]);
+ t.deepEqual(cast.toRgbColorList('#fff'), [255,255,255]);
+ t.deepEqual(cast.toRgbColorList('#ffffff'), [255,255,255]);
+
+ // Decimal (minimal, see "color" util tests)
+ t.deepEqual(cast.toRgbColorList(0), [0,0,0]);
+ t.deepEqual(cast.toRgbColorList(1), [0,0,1]);
+ t.deepEqual(cast.toRgbColorList(16777215), [255,255,255]);
+
+ // Malformed
+ t.deepEqual(cast.toRgbColorList('ffffff'), [0,0,0]);
+ t.deepEqual(cast.toRgbColorList('foobar'), [0,0,0]);
+ t.end();
+});
+
+test('compare', function (t) {
+ // Numeric
+ t.equal(cast.compare(0, 0), 0);
+ t.equal(cast.compare(1, 0), 1);
+ t.equal(cast.compare(0, 1), -1);
+ t.equal(cast.compare(1, 1), 0);
+
+ // String
+ t.equal(cast.compare('0', '0'), 0);
+ t.equal(cast.compare('0.1e10', '1000000000'), 0);
+ t.equal(cast.compare('foobar', 'FOOBAR'), 0);
+ t.equal(cast.compare('dog', 'cat'), 1);
+
+ // Boolean
+ t.equal(cast.compare(true, true), 0);
+ t.equal(cast.compare(true, false), 1);
+ t.equal(cast.compare(false, true), -1);
+ t.equal(cast.compare(true, true), 0);
+
+ // Undefined & object
+ t.equal(cast.compare(undefined, undefined), 0);
+ t.equal(cast.compare(undefined, 'undefined'), 0);
+ t.equal(cast.compare({}, {}), 0);
+ t.equal(cast.compare({}, '[object Object]'), 0);
+ t.end();
+});
+
+test('isInt', function (t) {
+ // Numeric
+ t.equal(cast.isInt(0), true);
+ t.equal(cast.isInt(1), true);
+ t.equal(cast.isInt(0.0), true);
+ t.equal(cast.isInt(3.14), false);
+ t.equal(cast.isInt(NaN), true);
+
+ // String
+ t.equal(cast.isInt('0'), true);
+ t.equal(cast.isInt('1'), true);
+ t.equal(cast.isInt('0.0'), false); // @todo This should be true
+ t.equal(cast.isInt('0.1e10'), false); // @todo This should be true
+ t.equal(cast.isInt('3.14'), false);
+
+ // Boolean
+ t.equal(cast.isInt(true), true);
+ t.equal(cast.isInt(false), true);
+
+ // Undefined & object
+ t.equal(cast.isInt(undefined), false);
+ t.equal(cast.isInt({}), false);
+ t.end();
+});
+
+test('toListIndex', function (t) {
+ var list = [0,1,2,3,4,5];
+ var empty = [];
+
+ // Valid
+ t.equal(cast.toListIndex(1, list.length), 1);
+ t.equal(cast.toListIndex(6, list.length), 6);
+
+ // Invalid
+ t.equal(cast.toListIndex(-1, list.length), 'INVALID');
+ t.equal(cast.toListIndex(0.1, list.length), 'INVALID');
+ t.equal(cast.toListIndex(0, list.length), 'INVALID');
+ t.equal(cast.toListIndex(7, list.length), 'INVALID');
+
+ // "all"
+ t.equal(cast.toListIndex('all', list.length), 'ALL');
+
+ // "last"
+ t.equal(cast.toListIndex('last', list.length), list.length);
+ t.equal(cast.toListIndex('last', empty.length), 'INVALID');
+
+ // "random"
+ var random = cast.toListIndex('random', list.length);
+ t.ok(random <= list.length);
+ t.ok(random > 0);
+ t.equal(cast.toListIndex('random', empty.length), 'INVALID');
+
+ // "any" (alias for "random")
+ var any = cast.toListIndex('any', list.length);
+ t.ok(any <= list.length);
+ t.ok(any > 0);
+ t.equal(cast.toListIndex('any', empty.length), 'INVALID');
+ t.end();
+});
diff --git a/test/unit/util_color.js b/test/unit/util_color.js
new file mode 100644
index 000000000..0558b4b3c
--- /dev/null
+++ b/test/unit/util_color.js
@@ -0,0 +1,62 @@
+var test = require('tap').test;
+var color = require('../../src/util/color');
+
+test('decimalToHex', function (t) {
+ t.equal(color.decimalToHex(0), '#000000');
+ t.equal(color.decimalToHex(1), '#000001');
+ t.equal(color.decimalToHex(16777215), '#ffffff');
+ t.equal(color.decimalToHex(-16777215), '#000001'); // @todo
+ t.equal(color.decimalToHex(99999999), '#5f5e0ff'); // @todo
+ t.end();
+});
+
+test('decimalToRgb', function (t) {
+ t.deepEqual(color.decimalToRgb(0), {r:0,g:0,b:0});
+ t.deepEqual(color.decimalToRgb(1), {r:0,g:0,b:1});
+ t.deepEqual(color.decimalToRgb(16777215), {r:255,g:255,b:255});
+ t.deepEqual(color.decimalToRgb(-16777215), {r:0,g:0,b:1}); // @todo
+ t.deepEqual(color.decimalToRgb(99999999), {r:245,g:224,b:255}); // @todo
+ t.end();
+});
+
+test('hexToRgb', function (t) {
+ t.deepEqual(color.hexToRgb('#000'), {r:0,g:0,b:0});
+ t.deepEqual(color.hexToRgb('#000000'), {r:0,g:0,b:0});
+ t.deepEqual(color.hexToRgb('#fff'), {r:255,g:255,b:255});
+ t.deepEqual(color.hexToRgb('#ffffff'), {r:255,g:255,b:255});
+ t.deepEqual(color.hexToRgb('#0fa'), {r:0,g:255,b:170});
+ t.deepEqual(color.hexToRgb('#00ffaa'), {r:0,g:255,b:170});
+
+ t.deepEqual(color.hexToRgb('000'), {r:0,g:0,b:0});
+ t.deepEqual(color.hexToRgb('fff'), {r:255,g:255,b:255});
+ t.deepEqual(color.hexToRgb('00ffaa'), {r:0,g:255,b:170});
+
+ t.deepEqual(color.hexToRgb('0'), null);
+ t.deepEqual(color.hexToRgb('hello world'), null);
+
+ t.end();
+});
+
+test('rgbToHex', function (t) {
+ t.equal(color.rgbToHex({r:0,g:0,b:0}), '#000000');
+ t.equal(color.rgbToHex({r:255,g:255,b:255}), '#ffffff');
+ t.equal(color.rgbToHex({r:0,g:255,b:170}), '#00ffaa');
+ t.end();
+});
+
+test('rgbToDecimal', function (t) {
+ t.equal(color.rgbToDecimal({r:0,g:0,b:0}), 0);
+ t.equal(color.rgbToDecimal({r:255,g:255,b:255}), 16777215);
+ t.equal(color.rgbToDecimal({r:0,g:255,b:170}), 65450);
+ t.end();
+});
+
+test('hexToDecimal', function (t) {
+ t.deepEqual(color.hexToDecimal('#000'), 0);
+ t.deepEqual(color.hexToDecimal('#000000'), 0);
+ t.deepEqual(color.hexToDecimal('#fff'), 16777215);
+ t.deepEqual(color.hexToDecimal('#ffffff'), 16777215);
+ t.deepEqual(color.hexToDecimal('#0fa'), 65450);
+ t.deepEqual(color.hexToDecimal('#00ffaa'), 65450);
+ t.end();
+});
diff --git a/test/unit/util_math.js b/test/unit/util_math.js
new file mode 100644
index 000000000..484b88c4b
--- /dev/null
+++ b/test/unit/util_math.js
@@ -0,0 +1,37 @@
+var test = require('tap').test;
+var math = require('../../src/util/math-util');
+
+test('degToRad', function (t) {
+ // @todo This is incorrect
+ t.equal(math.degToRad(0), 1.5707963267948966);
+ t.equal(math.degToRad(1), 1.5533430342749535);
+ t.equal(math.degToRad(180), -1.5707963267948966);
+ t.equal(math.degToRad(360), -4.71238898038469);
+ t.equal(math.degToRad(720), -10.995574287564276);
+ t.end();
+});
+
+test('radToDeg', function (t) {
+ t.equal(math.radToDeg(0), 0);
+ t.equal(math.radToDeg(1), 57.29577951308232);
+ t.equal(math.radToDeg(180), 10313.240312354817);
+ t.equal(math.radToDeg(360), 20626.480624709635);
+ t.equal(math.radToDeg(720), 41252.96124941927);
+ t.end();
+});
+
+test('clamp', function (t) {
+ t.equal(math.clamp(0, 0, 10), 0);
+ t.equal(math.clamp(1, 0, 10), 1);
+ t.equal(math.clamp(-10, 0, 10), 0);
+ t.equal(math.clamp(100, 0, 10), 10);
+ t.end();
+});
+
+test('wrapClamp', function (t) {
+ t.equal(math.wrapClamp(0, 0, 10), 0);
+ t.equal(math.wrapClamp(1, 0, 10), 1);
+ t.equal(math.wrapClamp(-10, 0, 10), 1);
+ t.equal(math.wrapClamp(100, 0, 10), 1);
+ t.end();
+});
diff --git a/test/unit/timer.js b/test/unit/util_timer.js
similarity index 100%
rename from test/unit/timer.js
rename to test/unit/util_timer.js
diff --git a/test/unit/util_xml.js b/test/unit/util_xml.js
new file mode 100644
index 000000000..8682d8323
--- /dev/null
+++ b/test/unit/util_xml.js
@@ -0,0 +1,9 @@
+var test = require('tap').test;
+var xml = require('../../src/util/xml-escape');
+
+test('escape', function (t) {
+ var input = '<foo bar="he & llo \'"></foo>';
+ var output = '<foo bar="he & llo '"></foo>';
+ t.equal(xml(input), output);
+ t.end();
+});