composer-lock-diff package allows you to see what packages have changed after you run composer update by comparing composer.lock to the the git HEAD.

Install

composer global require davidrjonas/composer-lock-diff:^1.0

# With zsh, run `rehash` to make it known to the shell.

# try it
composer-lock-diff --help

Usage

composer update
# don't commit yet!
composer-lock-diff