Create empty git base commit for a full code review

add_base_commit.sh

# create empty base commit that will be the reference for our code review
git checkout --orphan base
git rm -r --cached .
git clean -fxd
git commit --allow-empty -m "Start of the review"

# create and checkout review branch that will include the latest code that should be reviewed
git checkout -b review

# merge main branch into that new review branch
git merge main --allow-unrelated-histories --no-edit

# for a detailed explanation https://astrofrog.github.io/blog/2013/04/10/how-to-conduct-a-full-code-review-on-github/

Use the following to create a new commits with updates to the codebase that should be reviewed. This ensures the updates are theirs only.

# create and checkout updates branch that will contain new updated code that should be reviewed
git checkout -b updates

# merge changes from branch with code that should be reviewed (assuming `main` here), but without conflicts, the contents of 'ours' will be discarded later
git merge -s ours main --no-edit

# make temporary branch to merged commit
git branch temp

# get contents of working tree and index to the one of main
git reset --hard main

# reset to our merged commit but keep contents of working tree and index
git reset --soft temp

# change the contents of the merged commit with the contents of main
git commit --amend --no-edit

# get rid of our temporary branch
git branch -D temp

# verify that the merge commit contains only contents of main
git diff HEAD main