diff --git a/src/utils/event.js b/src/utils/event.js
index 354aeea..ac9119d 100644
--- a/src/utils/event.js
+++ b/src/utils/event.js
@@ -7,14 +7,13 @@ export function removeResizeEventListener(cb) {
 }
 
 export function createDispatcher(source) {
-  function dispatch(event, data) {
+  return function (event, data) {
     source.dispatchEvent(
       new CustomEvent(event, {
         detail: data,
       })
     )
   }
-  return dispatch
 }
 
 export function getIsTouchable() {
diff --git a/src/utils/math.test.js b/src/utils/math.test.js
new file mode 100644
index 0000000..1307b7c
--- /dev/null
+++ b/src/utils/math.test.js
@@ -0,0 +1,19 @@
+import {
+  getDistance,
+} from './math.js'
+
+describe('getDistance', () => {
+  it('returns correct distance between 2 points laying in one horizontal line', () => {
+    const p1 = { x: 0, y: 0 }
+    const p2 = { x: 5, y: 0 }
+
+    expect(getDistance(p1, p2)).toBe(5)
+  })
+
+  it('returns correct distance between 2 points', () => {
+    const p1 = { x: 1, y: 1 }
+    const p2 = { x: 5, y: 4 }
+
+    expect(getDistance(p1, p2)).toBe(5)
+  })
+})