feat: lowercase matched emails

Author: gajus

.README/README.md

@@ -45,6 +45,9 @@ extractEmail('extracts emails surrounded by odd unicode characters, e.g. 邮箱
 extractEmail('extracts emails surrounded by emojis, e.g. 📧gajus@gajus.com');
 // [{email: 'gajus@gajus.com'}]
 
+extractEmail('lowercases emails, e.g. GAJUS@GAJUS.COM');
+// [{email: 'gajus@gajus.com'}]
+
 extractEmail('excludes invalid emails with invalid TLDs, e.g. gajus@gajus.png');
 // []
 

src/normalizeInput.js

@@ -19,5 +19,6 @@ export default (input: string): string => {
 
     // Matches all ASCII characters from the space to tilde.
     .replace(/[^ -~]/g, ' ')
-    .trim();
+    .trim()
+    .toLowerCase();
 };

test/extract-email-address/extractEmail.js

@@ -5,6 +5,7 @@ import extractEmail from '../../src/extractEmail';
 
 const fixtures = [
   'gajus@gajus.com',
+  'GAJUS@GAJUS.COM',
   '：gajus@gajus.com',
   '📧gajus@gajus.com',
   'gajus@gajus.com.',

test/extract-email-address/normalizeInput.js

@@ -4,6 +4,7 @@ import test from 'ava';
 import normalizeInput from '../../src/normalizeInput';
 
 test('normalizes different email formats', (t) => {
+  t.is(normalizeInput('GAJUS@GAJUS.COM'), 'gajus@gajus.com');
   t.is(normalizeInput('：gajus@gajus.com'), 'gajus@gajus.com');
   t.is(normalizeInput('📧gajus@gajus.com'), 'gajus@gajus.com');
   t.is(normalizeInput('g a j u s [at] g a j u s [dot] c o m'), 'gajus@gajus.com');