I have sync-type = git in my repos.conf/gentoo.conf and I noticed that when I run
emerge --sync --ask
then it proceeds with the sync operation (i.e. it invokes git pull) as if the --ask flag was not specified. On the other hand, when the rsync sync-type is used, portage does respect the --ask flag and asks for user confirmation first.
Considering the new parallel sync code from bug 557426, we need to move the prompt somewhere before SyncRepos._sync begins syncing the repos in parallel (or else we could end up having multiple simultaneous prompts from concurrent sync jobs).