feat: parseFromUrl does not resolve relative references (asyncapi#504)

lib/parser.js

@@ -51,12 +51,12 @@ module.exports = {
  * @param {ParserOptions=} options Configuration options object {@link #asyncapiparserparseroptions--object|ParserOptions}
  * @returns {Promise<AsyncAPIDocument>} The parsed AsyncAPI document.
  */
-async function parse(asyncapiYAMLorJSON, options = {}) {
+async function parse(asyncapiYAMLorJSON, options = {}, urlRegExped) {
   let parsedJSON;
   let initialFormat;
 
-  options.path = options.path || `${process.cwd()}${path.sep}`;
-
+  options.path = options.path || urlRegExped || `${process.cwd()}${path.sep}`;
+  
   try {
     ({ initialFormat, parsedJSON } = toJS(asyncapiYAMLorJSON));
 
@@ -133,10 +133,22 @@ function parseFromUrl(url, fetchOptions, options) {
   //To not break the API by changing argument position and to silet the linter it is just better to move adding
   if (!fetchOptions) fetchOptions = {};
 
+  // RegExp, which chooses name of the file with spec in the URL string, is created.
+  const urlRegExp = /[^/]+$/g;
+  // When executed in multiple async calls, 'checkErrorWrapper' passes URL
+  // string as an object by reference. In this case 'String.replace()' method
+  // mutates original URL string causing test with multiple async calls to fail.
+  // Thus completely independent object containing URL string is created for
+  // future manipulation.
+  const urlCopy = new String(url);
+  // In the copy of the URL string, name of the file with spec is removed,
+  // leaving only absolute URL, which is later passed through thenable chain.
+  const urlRegExped = urlCopy.replace(urlRegExp.exec(urlCopy), '');
+
   return new Promise((resolve, reject) => {
     fetch(url, fetchOptions)
       .then(res => res.text())
-      .then(doc => parse(doc, options))
+      .then(doc => parse(doc, options, urlRegExped))
       .then(result => resolve(result))
       .catch(e => {
         if (e instanceof ParserError) return reject(e);