Details
There is a possibility that a user can add commit to accepted diff and then can push into main repository. I've a herald rule which prevents unaccepted revisions to get pushed into repository. But by tailgating commits into accepted diff, someone can push those commits into main repository directly.
Is there any way by which I can write a global rule to automatically trigger "request review" for updated revisions?
Please read comments on the answer of @avivey, that discussion led to reopening of this question.
Answers
The option is called "differential.sticky-accept":
Normally, when revisions that have been "Accepted" are updated, they remain "Accepted". This allows reviewers to suggest minor alterations when accepting, and encourages authors to update if they make minor changes in response to this feedback.
If you want updates to always require re-review, you can disable the "stickiness" of the "Accepted" status with this option. This may make the process for minor changes much more burdensome to both authors and reviewers.
For more background, see https://secure.phabricator.com/book/phabricator/article/differential_faq/#why-does-an-accepted-rev.