Improve loading of JSON files to avoid implicit behaviours of Node require (#1519)

Co-authored-by: Richard van der Hoff <1389908+richvdh@users.noreply.github.com>

src/utils.ts

@@ -15,6 +15,8 @@ limitations under the License.
 */
 
 import crypto from "crypto";
+import fs from "node:fs";
+import path from "node:path";
 
 export async function randomArray(size: number): Promise<string> {
     return new Promise((resolve, reject) => {
@@ -27,3 +29,20 @@ export async function randomArray(size: number): Promise<string> {
         });
     });
 }
+
+type JsonValue = null | string | number;
+type JsonArray = Array<JsonValue | JsonObject | JsonArray>;
+interface JsonObject {
+    [key: string]: JsonObject | JsonArray | JsonValue;
+}
+type Json = JsonArray | JsonObject;
+
+/**
+ * Synchronously load a JSON file from the local filesystem.
+ * Unlike `require`, will never execute any javascript in a loaded file.
+ * @param paths - An array of path segments which will be joined using the system's path delimiter.
+ */
+export function loadJsonFile<T extends Json>(...paths: string[]): T {
+    const file = fs.readFileSync(path.join(...paths), { encoding: "utf-8" });
+    return JSON.parse(file);
+}