update elements and fix some bugs

lib/src/prism/tests/helper/token-stream-transformer.js

Index: lib/src/prism/tests/helper/token-stream-transformer.js
diff --git a/lib/src/prism/tests/helper/token-stream-transformer.js b/lib/src/prism/tests/helper/token-stream-transformer.js
new file mode 100644
index 0000000000000000000000000000000000000000..deb831c45b982f276c710e7bca055aef2b08c5dd
--- /dev/null
+++ b/lib/src/prism/tests/helper/token-stream-transformer.js
@@ -0,0 +1,32 @@
+"use strict";
+
+
+module.exports = {
+	/**
+	 * Simplifies the token stream to ease the matching with the expected token stream.
+	 *
+	 * * Strings are kept as-is
+	 * * In arrays each value is transformed individually
+	 * * Values that are empty (empty arrays or strings only containing whitespace)
+	 *
+	 *
+	 * @param {Array} tokenStream
+	 * @returns {Array.<string[]|Array>}
+	 */
+	simplify: function (tokenStream) {
+		if (Array.isArray(tokenStream)) {
+			return tokenStream
+				.map(this.simplify.bind(this))
+				.filter(function (value) {
+					return !(Array.isArray(value) && !value.length) && !(typeof value === "string" && !value.trim().length);
+				}
+			);
+		}
+		else if (typeof tokenStream === "object") {
+			return [tokenStream.type, this.simplify(tokenStream.content)];
+		}
+		else {
+			return tokenStream;
+		}
+	}
+};