fix(core): LinearGauge tooltip + test

packages/core/src/components/ProgressBars/LinearGauge.test.tsx

@@ -0,0 +1,37 @@
+/*
+ * Copyright 2020 Spotify AB
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import React from 'react';
+import { renderInTestApp } from '@backstage/test-utils';
+
+import { LinearGauge } from './LinearGauge';
+
+describe('<LinearGauge />', () => {
+  it('renders without exploding', async () => {
+    const { getByTitle } = await renderInTestApp(<LinearGauge value={0.5} />);
+    expect(getByTitle('50%')).toBeInTheDocument();
+  });
+
+  it('renders progress and title', async () => {
+    const { container } = await renderInTestApp(<LinearGauge value={0 / 0} />);
+    expect(container).toBeEmptyDOMElement();
+  });
+
+  it('renders with 100 as max value', async () => {
+    const { getByTitle } = await renderInTestApp(<LinearGauge value={1.5} />);
+    expect(getByTitle('100%')).toBeInTheDocument();
+  });
+});

packages/core/src/components/ProgressBars/LinearGauge.tsx

@@ -40,12 +40,14 @@ export const LinearGauge: FC<Props> = ({ value }) => {
   const strokeColor = getProgressColor(theme.palette, percent, false, 100);
   return (
     <Tooltip title={`${percent}%`}>
-      <Line
-        percent={percent}
-        strokeWidth={4}
-        trailWidth={4}
-        strokeColor={strokeColor}
-      />
+      <span>
+        <Line
+          percent={percent}
+          strokeWidth={4}
+          trailWidth={4}
+          strokeColor={strokeColor}
+        />
+      </span>
     </Tooltip>
   );
 };