Fix wrong BTC sum when adding multiple line items

closes #220

tests/integration/components/add-reimbursement/component-test.js

@@ -1,6 +1,6 @@
 import { module, test } from 'qunit';
 import { setupRenderingTest } from 'ember-qunit';
-import { render } from '@ember/test-helpers';
+import { click, fillIn, render } from '@ember/test-helpers';
 import { hbs } from 'ember-cli-htmlbars';
 import contributors from '../../../fixtures/contributors';
 
@@ -22,7 +22,37 @@ module('Integration | Component | add-reimbursement', function(hooks) {
     assert.equal(this.element.querySelector('select#contributor option:checked').value, "3",
       'preselects the connected contributor account');
   });
+
+  test('Adding expense items', async function(assert) {
     await render(hbs`<AddReimbursement />`);
-    assert.ok(true);
+
+    assert.dom(this.element).includesText('New expense item');
+
+    await fillIn('form input[name="expense-amount"]', '49');
+    await fillIn('form input[name="expense-title"]', 'Domain kosmos.org (yearly fee)');
+    await click('form#add-expense-item input[type="submit"]');
+
+    assert.equal(this.element.querySelector('input[name="total-eur"]').value, '49',
+      'updates the total EUR amount');
+    assert.equal(this.element.querySelector('input[name="total-usd"]').value, '0',
+      'does not update the total USD amount');
+    assert.equal(this.element.querySelector('input[name="total-btc"]').value, '0.00534493',
+      'updates the total BTC amount');
+
+    assert.dom(this.element).doesNotIncludeText('New expense item');
+
+    await click('button#add-another-item');
+
+    await fillIn('form input[name="expense-amount"]', '29');
+    await fillIn('select[name="expense-currency"]', 'USD');
+    await fillIn('form input[name="expense-title"]', 'Domain kosmos.social (yearly fee)');
+    await click('form#add-expense-item input[type="submit"]');
+
+    assert.equal(this.element.querySelector('input[name="total-usd"]').value, '29',
+      'updates the total USD amount');
+    assert.equal(this.element.querySelector('input[name="total-eur"]').value, '49',
+      'does not update the total EUR amount');
+    assert.equal(this.element.querySelector('input[name="total-btc"]').value, '0.00804268',
+      'updates the total BTC amount');
   });
 });