Add support for new SQL keyword "materialized" in Prism (#333)

Author: BroFred

src/theme/prism-include-languages.js

@@ -0,0 +1,25 @@
+const newWords = ["materialized"].map((word) => {
+  return word.toLowerCase();
+});
+
+module.exports = function prismIncludeLanguages(Prism) {
+  if (Prism.languages.sql) {
+    const keywordPattern = Prism.languages.sql["keyword"];
+
+    // If it's a regex, convert to string, add new keywords, and recompile
+    if (keywordPattern instanceof RegExp) {
+      const patternStr = keywordPattern.source.replace(
+        /\)\\b$/,
+        `|${newWords.join("|")})\\b`
+      );
+      Prism.languages.sql["keyword"] = new RegExp(
+        patternStr,
+        keywordPattern.flags
+      );
+    } else if (Array.isArray(keywordPattern)) {
+      newWords.forEach((word) => {
+        keywordPattern.push(word);
+      });
+    }
+  }
+};