Client side meltdowns if you add a textfield and a combobox

[alump]

Setup:

• MacOS 10.14.5 (18F132)
• Intellij IDEA 2019.1.3
• Maven 3.6.1
• Amazon Corretto 11.0.3.7.1
• Spring boot starter for 14 RC3

Steps:

1. Download RC3 Spring Boot starter
2. Import to you IDEA
3. Add this line to MainView (after add(button);):
   add(new TextField(), new ComboBox<>());
4. Run app with mvn spring-boot:run

Expected outcome:
I can see app with button, textfield and combobox. Browser console isn't full of errors.

Actual outcome:
Following error starts browser console:
Uncaught DOMException: Failed to execute 'define' on 'CustomElementRegistry': the name "vaadin-text-field" has already been used with this registry
After this everything seams to be broken, and many of undefined errors follow.

Looks like combobox internally using textfield is causing re-registeration of textfield, while textfield itself has already caused registration?

[henrikerola]

This happened to me as well. Download a new project from https://start.vaadin.com/ and added a new view there containing add(new TextField(), new ComboBox<>());

[mstahv]

I tried this with servlet starter with Jetty and the whole servlet was undeployed (default servlet of jetty showed directory listing) when jetty was running.

When the "mvn jetty:run" was restarted, it worked correctly.

[mehdi-vaadin]

We should verify whether cleaning the project and removing package*.json files and node_modules folder and recreating them will solve this issue or not.

[ujoni]

Running rm -rf package-lock.json node_modules target does indeed solve the issues. However, a more elegant solution would not go amiss.

[ujoni]

This issue will likely be fixed with #6001 and #6046. They will be released with rc5 and this issue needs to be verified against the release candidate. Testing against a custom build works.

[ujoni]

I am unable to reproduce this issue using 14.0.0.rc5.

In addition, I am unable to reproduce the issue with starter following the steps:

• get spring starter from vaadin.com/start
• set Vaadin version to 14.0.0.rc3
• remove package-lock.json, package.json, webpack.config.js, and webpack.generated.js
• run either
  • mvn install
  • mvn spring-boot:run (and then kill process)
• upgrade version to 14.0.0.rc4
• add add(new TextField(), new ComboBox<>()); to MainView.java
• run either
  • mvn spring-boot:run
  • mvn clean spring-boot:run

In theory doing that should produce a project which is in the same state as the starter which was downloaded when 14.0.0.rc3 was the latest release.

I'll close this issues. If it pops up again, we'll tackle it then.