Easy way to have Homebrew list all package dependencies - homebrew

Question

Is there anyway to have the command brew show all the installed or optional dependencies for any given package? It would also be helpful to see which of the install packages are themselves the dependencies of others packages.

Answer 1

For all packages:
brew deps --tree --installed
For one package only (e.g.):
brew deps --tree --installed vim
Thanks to rob-kovacs for suggesting the --tree addition
See this helpful article for details: https://blog.jpalardy.com/posts/untangling-your-homebrew-dependencies/
Especially if you're interested in creating a graph of the dependency tree.

Answer 2

Here is a command that will list all formulas that aren't dependents of any other formulas (leaves), and for each of them lists all of its dependencies.
Sample output line:
awscli: gdbm readline sqlite tcl-tk xz
Command:
brew leaves | xargs brew deps --formula --for-each | sed "s/^.*:/$(tput setaf 4)&$(tput sgr0)/"
Alternate command without xargs:
brew deps --formula --for-each $(brew leaves) | sed "s/^.*:/$(tput setaf 4)&$(tput sgr0)/"

Answer 3

You can use info command like.
brew info ffmpeg
It will show you information and dependencies of formula. Also, it shows if this package installed by a tick after name of it.

Answer 4

I found the brew deps --tree switch is also very helpful to visualize dependencies just in the command line. From the official doc:
brew deps --tree [--1] [filters] [--annotate] (formulae|--installed):
Show dependencies as a tree. When given multiple formula arguments, output
individual trees for every formula.
Example1:
brew deps --tree fontconfig
Output1:
fontconfig
└── freetype
└── libpng
Example2:
brew deps --tree --1 fontconfig
Output2:
fontconfig
└── freetype
and there are more switches explained by:
brew help deps

Answer 5

Command:
brew deps --include-build --tree $(brew leaves)
Convenient alias:
alias brewdeps="brew leaves | xargs brew deps --include-build --tree"
This way you will get dependencies printed hierarchically and each package will be printed only once.