Open Workbench on an existing repo and navigate to the Commit view.
Click the "Branch" button, select "Open a new named branch" and type any name into the field. Click OK.
Click the "Options" button and check the "Push After Commit:" option. In the textfield, type "default" without quotes. Click OK.
Enter any commit message then click the "Commit" button.
Expected result: Workbench detects I'm pushing a new branch and prompts me with a dialog asking me if I really want to do this (similar to when "--pushafter=default" is not set and I do a commit, then push)
Actual result: push fails because Workbench invokes hg.exe without passing the "--new-branch" argument
Notes: the current "push new branch" behavior is a little retarded, in that it tries to push, then gets an error from hg telling it to use --new-branch, then pops up a dialog asking you if you actually want to push, and then only if you confirm does it actually push the new branch. Essentially it's doing a superfluous push, which it shouldn't need to do because it knows that a new branch is being pushed.