Add failing test

test/bugs/3199-sanitization-escaping.js

@@ -0,0 +1,23 @@
+/* eslint-env mocha */
+import React from "react"
+import expect from "expect"
+import { render } from "enzyme"
+import Markdown from "components/providers/markdown"
+
+describe("UI-3199: Sanitized Markdown causing code examples to be double escaped", function(){
+  it("should single-escape quotes", function(){
+
+    let str = "" +
+    "This is a test: \n\n" +
+    "    {\"abc\": \"def\"}\n"
+
+    let props = {
+      source: str
+    }
+
+    let el = render(<Markdown {...props}/>)
+
+    expect(el.find("code").first().text()).toEqual("{\"abc\": \"def\"}\n")
+    expect(el.find("code").first().html()).toEqual("{&quot;abc&quot;: &quot;def&quot;}\n")
+  })
+})