From 3a47bb38ace930bf55e675bfa01b35121bc2fb32 Mon Sep 17 00:00:00 2001
From: Paul Melnikow <github@paulmelnikow.com>
Date: Sat, 17 Mar 2018 16:52:41 -0400
Subject: [PATCH] Searches with regex control characters should not crash
 (#1579)

Fix #1578
---
 frontend/lib/prepare-examples.js      |  5 ++++-
 frontend/lib/prepare-examples.spec.js | 20 ++++++++++++++++++++
 package.json                          |  1 +
 3 files changed, 25 insertions(+), 1 deletion(-)
 create mode 100644 frontend/lib/prepare-examples.spec.js

diff --git a/frontend/lib/prepare-examples.js b/frontend/lib/prepare-examples.js
index 51c3e56313..787d395a1e 100644
--- a/frontend/lib/prepare-examples.js
+++ b/frontend/lib/prepare-examples.js
@@ -1,3 +1,5 @@
+import escapeStringRegexp from 'escape-string-regexp';
+
 export function exampleMatchesRegex(example, regex) {
   const { title, keywords } = example;
   const haystack = [title].concat(keywords).join(' ');
@@ -6,7 +8,8 @@ export function exampleMatchesRegex(example, regex) {
 
 export function predicateFromQuery(query) {
   if (query) {
-    const regex = new RegExp(query, 'i'); // Case-insensitive.
+    const escaped = escapeStringRegexp(query);
+    const regex = new RegExp(escaped, 'i'); // Case-insensitive.
     return example => exampleMatchesRegex(example, regex);
   } else {
     return () => true;
diff --git a/frontend/lib/prepare-examples.spec.js b/frontend/lib/prepare-examples.spec.js
new file mode 100644
index 0000000000..eedf187f0f
--- /dev/null
+++ b/frontend/lib/prepare-examples.spec.js
@@ -0,0 +1,20 @@
+import { test, given, forCases } from 'sazerac';
+import { predicateFromQuery } from './prepare-examples';
+
+describe('Badge example functions', function() {
+  const exampleMatchesQuery =
+    (example, query) => predicateFromQuery(query)(example);
+
+  test(exampleMatchesQuery, () => {
+    forCases([
+      given({ title: 'node version' }, 'npm'),
+    ]).expect(false);
+
+    forCases([
+      given({ title: 'node version', keywords: ['npm'] }, 'node'),
+      given({ title: 'node version', keywords: ['npm'] }, 'npm'),
+      // https://github.com/badges/shields/issues/1578
+      given({ title: 'c++ is the best language' }, 'c++'),
+    ]).expect(true);
+  });
+});
diff --git a/package.json b/package.json
index 0bb169ed88..108a04a245 100644
--- a/package.json
+++ b/package.json
@@ -25,6 +25,7 @@
     "camp": "~17.2.1",
     "chrome-web-store-item-property": "~1.1.2",
     "dot": "~1.1.2",
+    "escape-string-regexp": "^1.0.5",
     "gm": "^1.23.0",
     "json-autosave": "~1.1.2",
     "jsonpath": "~1.0.0",