--- a/client/src/components/__tests__/NoteInput.test.js	Thu Jun 01 11:39:20 2017 +0200
+++ b/client/src/components/__tests__/NoteInput.test.js	Thu Jun 01 15:20:31 2017 +0200
@@ -1,13 +1,14 @@
 import React from 'react';
 import { shallow, mount } from 'enzyme';
 import NoteInput from '../NoteInput';
+import { Plain } from 'slate'
 
 const setup = (propOverrides, doMount=false) => {
   const props = Object.assign({
       addNote: jest.fn()
   }, propOverrides);
 
-  const renderFn = doMount?mount:shallow; 
+  const renderFn = doMount?mount:shallow;
   const wrapper = renderFn(<NoteInput {...props} />);
 
   return {
@@ -16,10 +17,39 @@
   }
 };
 
+// Element.focus() doesn't work
+// @see https://stackoverflow.com/questions/42213522/mocking-document-createrange-for-jest
 beforeAll(() => {
   window.getSelection = () => {
     return {
-      removeAllRanges: () => {}
+      removeAllRanges: () => {},
+      addRange: () => {}
+    };
+  };
+
+  window.Range = function Range() {};
+
+  const createContextualFragment = (html) => {
+    const div = document.createElement('div');
+    div.innerHTML = html;
+    return div.children[0]; // so hokey it's not even funny
+  };
+
+  Range.prototype.createContextualFragment = (html) => createContextualFragment(html);
+
+  // HACK: Polyfil that allows codemirror to render in a JSDOM env.
+  window.document.createRange = function createRange() {
+    return {
+      setEnd: () => {},
+      setStart: () => {},
+      getBoundingClientRect: () => {
+        return { right: 0 };
+      },
+      compareBoundaryPoints: () => {
+        return 0;
+      },
+      getClientRects: () => [],
+      createContextualFragment,
     };
   };
 });
@@ -30,21 +60,39 @@
     expect(wrapper.exists()).toBe(true)
   });
 
-  test('click button', () => {
-      const { props, wrapper } = setup({}, true);
-      wrapper.find('button').simulate('click');
-      expect(props.addNote.mock.calls.length).toBe(1);
+  test('button is disabled when there is no text', () => {
+    const { props, wrapper } = setup({}, true);
+    const button = wrapper.find('button');
+
+    expect(button.prop('disabled')).toBe(true);
   });
 
-  test('note value on clickbutton', () => {
-      const { props, wrapper } = setup({}, true);
-      // This does nothing... must find a way to make it work
-      wrapper.find('SlateEditor').simulate('change', {target: {value: 'note text'}});
-      wrapper.find('button').simulate('click');
-      expect(props.addNote.mock.calls.length).toBe(1);
-      // cf. previous comment
-      //expect(props.addNote.mock.calls[0]).toEqual(['note text']);
+  test('button is not disabled when there is text', () => {
+    const { props, wrapper } = setup({}, true);
+    const button = wrapper.find('button');
+    const editor = wrapper.find('SlateEditor').find('Editor').node;
+
+    // FIXME simulate('change') doesn't work
+    editor.onChange(Plain.deserialize('Hello world'));
+
+    expect(button.prop('disabled')).toBe(false);
   });
 
+  // test('click button', () => {
+  //     const { props, wrapper } = setup({}, true);
+  //     wrapper.find('button').simulate('click');
+  //     expect(props.addNote.mock.calls.length).toBe(1);
+  // });
+
+  // test('note value on clickbutton', () => {
+  //     const { props, wrapper } = setup({}, true);
+  //     // This does nothing... must find a way to make it work
+  //     wrapper.find('SlateEditor').simulate('change', {target: {value: 'note text'}});
+  //     wrapper.find('button').simulate('click');
+  //     expect(props.addNote.mock.calls.length).toBe(1);
+  //     // cf. previous comment
+  //     //expect(props.addNote.mock.calls[0]).toEqual(['note text']);
+  // });
+
 });
 

--- a/client/src/store/configureStore.js	Thu Jun 01 11:39:20 2017 +0200
+++ b/client/src/store/configureStore.js	Thu Jun 01 15:20:31 2017 +0200
@@ -10,7 +10,9 @@
       return {};
     }
     return JSON.parse(serializedState);
-  } catch (err) {}
+  } catch (err) {
+    return {};
+  }
 }
 
 const saveState = (state) => {