feat(bom): allow processing of json files with BOM

Author: jonluca

lib/parsers/json.ts

@@ -21,6 +21,11 @@ export default {
    */
   canParse: ".json",
 
+  /**
+   * Allow JSON files with byte order marks (BOM)
+   */
+  allowBOM: true,
+
   /**
    * Parses the given file as JSON
    */
@@ -37,6 +42,17 @@ export default {
         try {
           return JSON.parse(data);
         } catch (e: any) {
+          if (this.allowBOM) {
+            try {
+              // find the first curly brace
+              const firstCurlyBrace = data.indexOf("{");
+              // remove any characters before the first curly brace
+              data = data.slice(firstCurlyBrace);
+              return JSON.parse(data);
+            } catch (e: any) {
+              throw new ParserError(e.message, file.url);
+            }
+          }
           throw new ParserError(e.message, file.url);
         }
       }

lib/types/index.ts

@@ -88,6 +88,13 @@ export interface Plugin {
    */
   allowEmpty?: boolean;
 
+  /**
+   * Specifies whether a Byte Order Mark (BOM) is allowed or not. Only applies to JSON parsing
+   *
+   * @type {boolean} @default true
+   */
+  allowBOM?: boolean;
+
   /**
    * The encoding that the text is expected to be in.
    */