From: Alexandr Miloslavskiy <alexandr.miloslavskiy@syntevo.com>
Date: Fri, 06 Aug 2021 00:04:46 GMT
Subject: [BUG] Amending a shallow clone -> orphan branch
Message-ID: <64760969-1ead-2bfb-6f98-1161d385c0ca@syntevo.com>

Consider the following steps :

git clone --depth 1 --single-branch --branch master 
https://github.com/git/git
cd git
 >1.txt
git add 1.txt
git commit --amend

This results in an orphaned branch, where a single commit contains 
entire tree.

I understand that this is a bug, because certainly git knew shallow 
commit's parents and could reuse that when amending?