Updated based on PR feedback

packages/teams-js/src/internal/utils.ts

@@ -429,9 +429,27 @@ export function validateUrl(url: URL, errorToThrow?: Error): void {
   }
 }
 
-export function fullyQualifyUrlString(urlString: string): URL {
+/**
+ * This function takes in a string that represents a full or relative path and returns a
+ * fully qualified URL object.
+ *
+ * Currently this is accomplished by assigning the input string to an a tag and then retrieving
+ * the a tag's href value. A side effect of doing this is that the string becomes a fully qualified
+ * URL. This is probably not how I would choose to do this, but in order to not unintentionally
+ * break something I've preseved the functionality here and just isolated the code to make it
+ * easier to mock.
+ *
+ * @example
+ *    `fullyQualifyUrlString('https://example.com')` returns `new URL('https://example.com')`
+ *    `fullyQualifyUrlString('helloWorld')` returns `new URL('https://example.com/helloWorld')`
+ *    `fullyQualifyUrlString('hello%20World')` returns `new URL('https://example.com/hello%20World')`
+ *
+ * @param fullOrRelativePath A string representing a full or relative URL.
+ * @returns A fully qualified URL representing the input string.
+ */
+export function fullyQualifyUrlString(fullOrRelativePath: string): URL {
   const link = document.createElement('a');
-  link.href = urlString;
+  link.href = fullOrRelativePath;
   return new URL(link.href);
 }
 

packages/teams-js/src/public/authentication.ts

@@ -350,8 +350,8 @@ export namespace authentication {
     height = Math.min(height, Communication.currentWindow.outerHeight - 200);
 
     // Convert any relative URLs into absolute URLs before sending them over to the parent window
-    const qualifiedURL = fullyQualifyUrlString(authenticateParameters.url.replace('{oauthRedirectMethod}', 'web'));
-    validateUrl(qualifiedURL);
+    const fullyQualifiedURL = fullyQualifyUrlString(authenticateParameters.url.replace('{oauthRedirectMethod}', 'web'));
+    validateUrl(fullyQualifiedURL);
 
     // We are running in the browser, so we need to center the new window ourselves
     let left: number =
@@ -366,7 +366,7 @@ export namespace authentication {
     top += Communication.currentWindow.outerHeight / 2 - height / 2;
     // Open a child window with a desired set of standard browser features
     Communication.childWindow = Communication.currentWindow.open(
-      qualifiedURL.href,
+      fullyQualifiedURL.href,
       '_blank',
       'toolbar=no, location=yes, status=no, menubar=no, scrollbars=yes, top=' +
         top +