From 4d8e9cacdd5b3833ae4a52bfe1ae9ad0a6a3104d Mon Sep 17 00:00:00 2001
From: HaNdTriX <HaNdTriX@users.noreply.github.com>
Date: Mon, 13 Aug 2018 20:03:59 +0200
Subject: [PATCH] Improve getDisplayName util (#4944)

- [x] Add unit test
- [x] Allow to get the display name of a native component (e.g.: `div`) without throwing
- [ ] Remove displayName in production mode
---
 lib/utils.js                     |  4 ++++
 test/unit/getDisplayName.test.js | 30 ++++++++++++++++++++++++++++++
 2 files changed, 34 insertions(+)
 create mode 100644 test/unit/getDisplayName.test.js

diff --git a/lib/utils.js b/lib/utils.js
index c1daa56f..a36d3e41 100644
--- a/lib/utils.js
+++ b/lib/utils.js
@@ -46,6 +46,10 @@ export function printAndExit (message, code = 1) {
 }
 
 export function getDisplayName (Component) {
+  if (typeof Component === 'string') {
+    return Component
+  }
+
   return Component.displayName || Component.name || 'Unknown'
 }
 
diff --git a/test/unit/getDisplayName.test.js b/test/unit/getDisplayName.test.js
new file mode 100644
index 00000000..8181de67
--- /dev/null
+++ b/test/unit/getDisplayName.test.js
@@ -0,0 +1,30 @@
+/* global describe, it, expect */
+import { Component } from 'react'
+import { getDisplayName } from '../../dist/lib/utils'
+
+describe('getDisplayName', () => {
+  it('gets the proper display name of a component', () => {
+    class ComponentOne extends Component {
+      render () {
+        return null
+      }
+    }
+
+    class ComponentTwo extends Component {
+      static displayName = 'CustomDisplayName'
+      render () {
+        return null
+      }
+    }
+
+    function FunctionalComponent () {
+      return null
+    }
+
+    expect(getDisplayName(ComponentOne)).toBe('ComponentOne')
+    expect(getDisplayName(ComponentTwo)).toBe('CustomDisplayName')
+    expect(getDisplayName(FunctionalComponent)).toBe('FunctionalComponent')
+    expect(getDisplayName(() => null)).toBe('Unknown')
+    expect(getDisplayName('div')).toBe('div')
+  })
+})