Resolve warning when code block has no language

Author: jsakas

lib/markdown-to-react-loader.js

@@ -32,11 +32,16 @@ function processCodeBlock (code, lang) {
   // users can easily type in any language they want,
   // we don't want the app to blow up in case of bad input.
   try {
-    require(`prismjs/components/prism-${lang}`);
-    className = `language-${lang}`;
-    highlighter = Prism.languages[lang];
+    if (typeof lang === 'undefined') {
+      className = '';
+      highlighter = '';
+    } else {
+      require(`prismjs/components/prism-${lang}`);
+      className = `language-${lang}`;
+      highlighter = Prism.languages[lang];
+    }
   } catch (e) {
-    console.warn(`Could not find PrismJS language ${lang}`);
+    console.warn(`Could not find PrismJS language ${lang}`, e);
     className = '';
     highlighter = '';
   }

test/all.test.js

@@ -50,6 +50,6 @@ test('Converts tables and table cells', () => {
   expectIO('io/table.md', 'io/table.js');
 });
 
-test('It can render everything', () => {
+test('Can render everything', () => {
   expectIO('io/everything.md', 'io/everything.js');
 });