add KeymapsForm test

src/settings/components/form/keymaps-form.jsx

@@ -58,6 +58,10 @@ const KeyMapFields = [
 class KeymapsForm extends Component {
 
   render() {
+    let values = this.props.value;
+    if (!values) {
+      values = {};
+    }
     return <div className='keymap-fields'>
       {
         KeyMapFields.map((group, index) => {
@@ -66,7 +70,7 @@ class KeymapsForm extends Component {
               group.map((field) => {
                 let name = field[0];
                 let label = field[1];
-                let value = this.props.value[name];
+                let value = values[name];
                 return <Input
                   type='text' id={name} name={name} key={name}
                   label={label} value={value}

test/settings/components/form/keymaps-form.test.jsx

@@ -0,0 +1,53 @@
+import { expect } from 'chai';
+import { h, render } from 'preact';
+import KeymapsForm from 'settings/components/form/keymaps-form'
+
+describe("settings/form/KeymapsForm", () => {
+  beforeEach(() => {
+    document.body.innerHTML = '';
+  });
+
+  describe('render', () => {
+    it('renders KeymapsForm', () => {
+      render(<KeymapsForm value={{
+        'scroll.vertically?{"count":1}': 'j',
+        'scroll.vertically?{"count":-1}': 'k',
+      }} />, document.body);
+
+      let inputj = document.getElementById('scroll.vertically?{"count":1}');
+      let inputk = document.getElementById('scroll.vertically?{"count":-1}');
+
+      expect(inputj.value).to.equal('j');
+      expect(inputk.value).to.equal('k');
+    });
+
+    it('renders blank value', () => {
+      render(<KeymapsForm />, document.body);
+
+      let inputj = document.getElementById('scroll.vertically?{"count":1}');
+      let inputk = document.getElementById('scroll.vertically?{"count":-1}');
+
+      expect(inputj.value).to.be.empty;
+      expect(inputk.value).to.be.empty;
+    });
+  });
+
+  describe('onChange event', () => {
+    it('invokes onChange event on edit', (done) => {
+      render(<KeymapsForm
+        value={{
+          'scroll.vertically?{"count":1}': 'j',
+          'scroll.vertically?{"count":-1}': 'k',
+        }}
+        onChange={value => {
+          expect(value['scroll.vertically?{"count":1}']).to.equal('jjj');
+
+          done();
+        }} />, document.body);
+
+      let input = document.getElementById('scroll.vertically?{"count":1}');
+      input.value = 'jjj';
+      input.dispatchEvent(new Event('change'))
+    });
+  });
+});