diff --git a/tests/attributes.test.js b/tests/attributes.test.js
index 3ef48ed56b5..c1bf87b345e 100644
--- a/tests/attributes.test.js
+++ b/tests/attributes.test.js
@@ -1,5 +1,5 @@
-var expect = require("chai").expect;
-var Point = require("../dist/index.js").Point;
+let expect = require("chai").expect;
+let Point = require("../dist/index.js").Point;
 
 function newAttr() {
   return new Point(0, 0).attributes;
diff --git a/tests/hooks.test.js b/tests/hooks.test.js
index dccd1c3179e..8ddc3231582 100644
--- a/tests/hooks.test.js
+++ b/tests/hooks.test.js
@@ -1,8 +1,8 @@
-var expect = require("chai").expect;
-var freesewing = require("../dist/index.js");
+let expect = require("chai").expect;
+let freesewing = require("../dist/index.js");
 
-var pattern = new freesewing.Pattern();
-var h = pattern.hooks;
+let pattern = new freesewing.Pattern();
+let h = pattern.hooks;
 
 it("Should contain all hooks", () => {
   let test = [
@@ -38,11 +38,11 @@ it("Should not attach a non-existing hook", () => {
   expect(h.attach("no-such-hook", obj)).to.equal(undefined);
 });
 
-var count = 0;
-var pre = function() {
+let count = 0;
+let pre = function() {
   count += 5;
 };
-var post = function() {
+let post = function() {
   count = count * -1;
 };
 
diff --git a/tests/part.test.js b/tests/part.test.js
new file mode 100644
index 00000000000..d7a70ac9efa
--- /dev/null
+++ b/tests/part.test.js
@@ -0,0 +1,116 @@
+let expect = require("chai").expect;
+let freesewing = require("../dist/index.js");
+
+it("Svg constructor should initialize object", () => {
+  let pattern = new freesewing.Pattern();
+  let part = new pattern.Part();
+  expect(part.paths).to.eql({});
+  expect(part.snippets).to.eql({});
+  expect(part.freeId).to.equal(0);
+  expect(part.topLeft).to.equal(false);
+  expect(part.bottomRight).to.equal(false);
+  expect(part.width).to.equal(false);
+  expect(part.height).to.equal(false);
+  expect(part.render).to.equal(true);
+  expect(part.points.origin.x).to.equal(0);
+  expect(part.points.origin.y).to.equal(0);
+});
+
+it("Should return a function from macroClosure", () => {
+  let pattern = new freesewing.Pattern();
+  let part = new pattern.Part();
+  expect(typeof part.macroClosure()).to.equal("function");
+});
+
+it("Should no run an unknown macro", () => {
+  let pattern = new freesewing.Pattern();
+  let part = new pattern.Part();
+  let macro = part.macroClosure();
+  expect(macro("unknown")).to.equal(undefined);
+});
+
+it("Should register and run a macro", () => {
+  let pattern = new freesewing.Pattern();
+  let plugin = {
+    name: "test",
+    version: "0.1-test",
+    macros: {
+      test: function(so) {
+        let points = this.points;
+        points.macro = new this.Point(so.x, so.y);
+      }
+    }
+  };
+  pattern.with(plugin);
+  let part = new pattern.Part();
+  let macro = part.macroClosure();
+  macro("test", { x: 123, y: 456 });
+  expect(part.points.macro.x).to.equal(123);
+  expect(part.points.macro.y).to.equal(456);
+});
+
+it("Should run debug", () => {
+  let pattern = new freesewing.Pattern();
+  let part = new pattern.Part();
+  let debug = part.debugClosure();
+  expect(typeof debug).to.equal("function");
+  let d = 1;
+  let e = 11;
+  let b = 111;
+  let u = 1111;
+  let g = 11111;
+  expect(debug(d, e, b, u, g)).to.equal(undefined);
+});
+
+it("Should return a free ID", () => {
+  let pattern = new freesewing.Pattern();
+  let part = new pattern.Part();
+  let free = part.getUid();
+  expect(part.getUid()).to.equal("" + (parseInt(free) + 1));
+});
+
+it("Should return a function from unitsClosure", () => {
+  let pattern = new freesewing.Pattern();
+  let part = new pattern.Part();
+  expect(typeof part.unitsClosure()).to.equal("function");
+});
+
+it("Should convert units", () => {
+  let pattern = new freesewing.Pattern();
+  let part = new pattern.Part();
+  let units = part.unitsClosure();
+  expect(units(123.456)).to.equal("12.35cm");
+  expect(part.units(123.456)).to.equal("12.35cm");
+});
+
+it("Should set part attributes", () => {
+  let pattern = new freesewing.Pattern();
+  let part = new pattern.Part();
+  part.attr("foo", "bar");
+  expect(part.attributes.get("foo")).to.equal("bar");
+  part.attr("foo", "baz");
+  expect(part.attributes.get("foo")).to.equal("bar baz");
+  part.attr("foo", "schmoo", true);
+  expect(part.attributes.get("foo")).to.equal("schmoo");
+});
+
+it("Should copy an part", () => {
+  let pattern = new freesewing.Pattern();
+  let part = new pattern.Part();
+  part.points.origin.x = 16;
+  part.points.foo = new part.Point(12, 23);
+  let test = new pattern.Part();
+  test.copy(part);
+  expect(test.points.origin.x).to.equal(0);
+  expect(test.points.foo.x).to.equal(12);
+});
+
+it("Should return shorthand", () => {
+  let pattern = new freesewing.Pattern();
+  pattern.settings.mode = "draft";
+  pattern.settings.paperless = true;
+  let part = new pattern.Part();
+  let short = part.shorthand();
+  expect(short.final).to.equal(true);
+  expect(short.paperless).to.equal(true);
+});
diff --git a/tests/point.test.js b/tests/point.test.js
index 71e86a154b3..728c162650a 100644
--- a/tests/point.test.js
+++ b/tests/point.test.js
@@ -1,5 +1,5 @@
-var expect = require("chai").expect;
-var Point = require("../dist/index.js").Point;
+let expect = require("chai").expect;
+let Point = require("../dist/index.js").Point;
 
 it("Should return point object", () => {
   let result = new Point(2, 4);
diff --git a/tests/snippet.test.js b/tests/snippet.test.js
index 7b3a2096740..374c40c99c6 100644
--- a/tests/snippet.test.js
+++ b/tests/snippet.test.js
@@ -1,8 +1,8 @@
-var expect = require("chai").expect;
-var freesewing = require("../dist/index.js");
+let expect = require("chai").expect;
+let freesewing = require("../dist/index.js");
 
 it("Should create a snippet", () => {
-  var snip1 = new freesewing.Snippet(
+  let snip1 = new freesewing.Snippet(
     "test",
     new freesewing.Point(12, 34),
     "this is an example"
@@ -14,12 +14,12 @@ it("Should create a snippet", () => {
 });
 
 it("Should default to empty description", () => {
-  var snip2 = new freesewing.Snippet("test", new freesewing.Point(12, 34));
+  let snip2 = new freesewing.Snippet("test", new freesewing.Point(12, 34));
   expect(snip2.description).to.equal("");
 });
 
 it("Should clone a snippet", () => {
-  var snip3 = new freesewing.Snippet(
+  let snip3 = new freesewing.Snippet(
     "boo",
     new freesewing.Point(56, 78),
     "clone me"
diff --git a/tests/store.test.js b/tests/store.test.js
index 93f0e08c030..5fdac207f23 100644
--- a/tests/store.test.js
+++ b/tests/store.test.js
@@ -1,8 +1,8 @@
-var expect = require("chai").expect;
-var freesewing = require("../dist/index.js");
+let expect = require("chai").expect;
+let freesewing = require("../dist/index.js");
 
-var pattern = new freesewing.Pattern();
-var store = pattern.store;
+let pattern = new freesewing.Pattern();
+let store = pattern.store;
 
 it("Store should be a Map", () => {
   expect(store.data.toString()).to.equal("[object Map]");
diff --git a/tests/svg.test.js b/tests/svg.test.js
index 51842397e3a..f6a4c8a5822 100644
--- a/tests/svg.test.js
+++ b/tests/svg.test.js
@@ -1,12 +1,12 @@
-var version = require("../package.json").version;
-var render = require("./fixtures/render.js");
-var expect = require("chai").expect;
-var chai = require("chai");
+let version = require("../package.json").version;
+let render = require("./fixtures/render.js");
+let expect = require("chai").expect;
+let chai = require("chai");
 chai.use(require("chai-string"));
-var freesewing = require("../dist/index.js");
+let freesewing = require("../dist/index.js");
 
 it("Svg constructor should initialize object", () => {
-  var pattern = new freesewing.Pattern();
+  let pattern = new freesewing.Pattern();
   pattern.render();
   let svg = pattern.svg;
   expect(svg.openGroups).to.eql([]);
@@ -35,12 +35,12 @@ it("Svg constructor should initialize object", () => {
 });
 
 it("Should render Svg boilerplate", () => {
-  var pattern = new freesewing.Pattern();
+  let pattern = new freesewing.Pattern();
   expect(pattern.render()).to.equalIgnoreSpaces(render.boilerplate);
 });
 
 it("Should render Svg part boilerplate", () => {
-  var pattern = new freesewing.Pattern();
+  let pattern = new freesewing.Pattern();
   pattern.render();
   let svg = pattern.svg;
   pattern.parts.test = new pattern.Part();
@@ -50,7 +50,7 @@ it("Should render Svg part boilerplate", () => {
 });
 
 it("Should render Svg path", () => {
-  var pattern = new freesewing.Pattern();
+  let pattern = new freesewing.Pattern();
   pattern.render();
   let svg = pattern.svg;
   pattern.parts.test = new pattern.Part();
@@ -65,7 +65,7 @@ it("Should render Svg path", () => {
   expect(pattern.render()).to.equalIgnoreSpaces(render.path);
 });
 it("Should not render Svg path when render property is false", () => {
-  var pattern = new freesewing.Pattern();
+  let pattern = new freesewing.Pattern();
   pattern.render();
   let svg = pattern.svg;
   pattern.parts.test = new pattern.Part();
@@ -83,7 +83,7 @@ it("Should not render Svg path when render property is false", () => {
 //console.log(pattern.render());
 
 it("Should render Svg text", () => {
-  var pattern = new freesewing.Pattern();
+  let pattern = new freesewing.Pattern();
   pattern.render();
   let svg = pattern.svg;
   pattern.parts.test = new pattern.Part();
@@ -96,7 +96,7 @@ it("Should render Svg text", () => {
 });
 
 it("Should not render empty text", () => {
-  var pattern = new freesewing.Pattern();
+  let pattern = new freesewing.Pattern();
   pattern.render();
   let svg = pattern.svg;
   pattern.parts.test = new pattern.Part();
@@ -108,7 +108,7 @@ it("Should not render empty text", () => {
 });
 
 it("Should render Svg text on path", () => {
-  var pattern = new freesewing.Pattern();
+  let pattern = new freesewing.Pattern();
   pattern.render();
   let svg = pattern.svg;
   pattern.parts.test = new pattern.Part();
@@ -125,7 +125,7 @@ it("Should render Svg text on path", () => {
 });
 
 it("Should render Svg text on path, center aligned", () => {
-  var pattern = new freesewing.Pattern();
+  let pattern = new freesewing.Pattern();
   pattern.render();
   let svg = pattern.svg;
   pattern.parts.test = new pattern.Part();
@@ -142,7 +142,7 @@ it("Should render Svg text on path, center aligned", () => {
 });
 
 it("Should render Svg text on path, right aligned", () => {
-  var pattern = new freesewing.Pattern();
+  let pattern = new freesewing.Pattern();
   pattern.render();
   let svg = pattern.svg;
   pattern.parts.test = new pattern.Part();
@@ -159,7 +159,7 @@ it("Should render Svg text on path, right aligned", () => {
 });
 
 it("Should render an Svg snippet", () => {
-  var pattern = new freesewing.Pattern();
+  let pattern = new freesewing.Pattern();
   pattern.render();
   let svg = pattern.svg;
   pattern.parts.test = new pattern.Part();
diff --git a/tests/utils.test.js b/tests/utils.test.js
index 61ccb50877a..f89b5161df0 100644
--- a/tests/utils.test.js
+++ b/tests/utils.test.js
@@ -1,81 +1,81 @@
-var expect = require("chai").expect;
-var freesewing = require("../dist/index.js");
-var utils = freesewing.utils;
+let expect = require("chai").expect;
+let freesewing = require("../dist/index.js");
+let utils = freesewing.utils;
 
 it("Should return the correct macro name", () => {
   expect(utils.macroName("test")).to.equal("_macro_test");
 });
 
 it("Should find the intersection of two endless line segments", () => {
-  var a = new freesewing.Point(10, 20);
-  var b = new freesewing.Point(20, 24);
-  var c = new freesewing.Point(90, 19);
-  var d = new freesewing.Point(19, 70);
-  var X = freesewing.utils.beamsCross(a, b, c, d);
+  let a = new freesewing.Point(10, 20);
+  let b = new freesewing.Point(20, 24);
+  let c = new freesewing.Point(90, 19);
+  let d = new freesewing.Point(19, 70);
+  let X = freesewing.utils.beamsCross(a, b, c, d);
   expect(X.x).to.equal(60.49);
   expect(X.y).to.equal(40.2);
 });
 
 it("Should detect parallel lines", () => {
-  var a = new freesewing.Point(10, 20);
-  var b = new freesewing.Point(20, 20);
-  var c = new freesewing.Point(90, 40);
-  var d = new freesewing.Point(19, 40);
+  let a = new freesewing.Point(10, 20);
+  let b = new freesewing.Point(20, 20);
+  let c = new freesewing.Point(90, 40);
+  let d = new freesewing.Point(19, 40);
   expect(freesewing.utils.beamsCross(a, b, c, d)).to.equal(false);
   expect(freesewing.utils.linesCross(a, b, c, d)).to.equal(false);
 });
 
 it("Should detect vertical lines", () => {
-  var a = new freesewing.Point(10, 20);
-  var b = new freesewing.Point(10, 90);
-  var c = new freesewing.Point(90, 40);
-  var d = new freesewing.Point(19, 40);
-  var X = freesewing.utils.beamsCross(a, b, c, d);
+  let a = new freesewing.Point(10, 20);
+  let b = new freesewing.Point(10, 90);
+  let c = new freesewing.Point(90, 40);
+  let d = new freesewing.Point(19, 40);
+  let X = freesewing.utils.beamsCross(a, b, c, d);
   expect(X.x).to.equal(10);
   expect(X.y).to.equal(40);
-  var X = freesewing.utils.beamsCross(c, d, a, b);
+  X = freesewing.utils.beamsCross(c, d, a, b);
   expect(X.x).to.equal(10);
 });
 
 it("Should swap direction prior to finding beam intersection", () => {
-  var a = new freesewing.Point(10, 20);
-  var b = new freesewing.Point(00, 90);
-  var c = new freesewing.Point(90, 40);
-  var d = new freesewing.Point(19, 40);
-  var X = freesewing.utils.beamsCross(a, b, c, d);
+  let a = new freesewing.Point(10, 20);
+  let b = new freesewing.Point(00, 90);
+  let c = new freesewing.Point(90, 40);
+  let d = new freesewing.Point(19, 40);
+  let X = freesewing.utils.beamsCross(a, b, c, d);
   expect(X.x).to.equal(7.14);
   expect(X.y).to.equal(40);
 });
 
 it("Should return false when two lines don't intersect", () => {
-  var a = new freesewing.Point(10, 20);
-  var b = new freesewing.Point(20, 24);
-  var c = new freesewing.Point(90, 19);
-  var d = new freesewing.Point(19, 70);
+  let a = new freesewing.Point(10, 20);
+  let b = new freesewing.Point(20, 24);
+  let c = new freesewing.Point(90, 19);
+  let d = new freesewing.Point(19, 70);
   expect(freesewing.utils.linesCross(a, b, c, d)).to.equal(false);
 });
 
 it("Should find the intersection of two line segments", () => {
-  var a = new freesewing.Point(10, 10);
-  var b = new freesewing.Point(90, 74);
-  var c = new freesewing.Point(90, 19);
-  var d = new freesewing.Point(11, 70);
-  var X = freesewing.utils.beamsCross(a, b, c, d);
+  let a = new freesewing.Point(10, 10);
+  let b = new freesewing.Point(90, 74);
+  let c = new freesewing.Point(90, 19);
+  let d = new freesewing.Point(11, 70);
+  let X = freesewing.utils.beamsCross(a, b, c, d);
   expect(X.x).to.equal(51.95);
   expect(X.y).to.equal(43.56);
 });
 
 it("Should find the intersection of an endles line and a give Y-value", () => {
-  var a = new freesewing.Point(10, 10);
-  var b = new freesewing.Point(90, 74);
-  var X = freesewing.utils.beamCrossesY(a, b, 69);
+  let a = new freesewing.Point(10, 10);
+  let b = new freesewing.Point(90, 74);
+  let X = freesewing.utils.beamCrossesY(a, b, 69);
   expect(X.x).to.equal(83.75);
   expect(X.y).to.equal(69);
 });
 
 it("Should detect horizontal lines never pass a give Y-value", () => {
-  var a = new freesewing.Point(10, 10);
-  var b = new freesewing.Point(90, 10);
+  let a = new freesewing.Point(10, 10);
+  let b = new freesewing.Point(90, 10);
   expect(freesewing.utils.beamCrossesY(a, b, 69)).to.equal(false);
 });