We’re very excited to introduce a new way of triggering pipelines from our VS Code extension.
From version 2.0, our new Run Panel lets you trigger pipelines from VS Code based on your local, unversioned config.yml file, rather than the one versioned on your branch.
Triggering pipelines from VS Code lets you to iterate on your CircleCI config without committing your trial and error changes to your version control system. Test out your config changes, and only commit them when you are happy with them.
You can choose to run your full pipeline, or select only the individual jobs and workflows you want to validate, by using checkboxes. 
View the results of your test runs in the extension pipelines panel or in the CircleCI web app, just the same as any other pipeline.
The ability to trigger a pipeline from VS Code with an unversioned config is currently in closed preview . This feature is available on the Free Plan for projects integrated through the GitHub OAuth app , or Bitbucket . To find out which GitHub account type you have, see the documentation about GitHub OAuth app integration. If you are on the Performance of Scale plan, and would like to sign up for the closed preview, you can do so here.
Notes:
- You need to opt-in to this feature per project. Navigate to Project Settings > VS Code integration in the web app, and toggle the setting “Run pipelines with unversioned config” to On.
- This feature is disabled for projects that use dynamic configuration
- Please be mindful when running pipelines with unversioned configuration, and take care to ensure no job with unintended effects is included in the run. In particular, we recommend only using this feature only on feature branches.
- Test run pipelines triggered from VS Code have access to contexts and project environment variables, based on which branch they are run on
- At this time, audit logs do not mention that a pipeline was run with unversioned config, and PR status checks may be altered as a result of unversioned config overrides. Both issues will be addressed in the coming weeks.
Find more information in the official documentation.