Determine flags that were given for packages installed with homebrew

Question

Is there a way to check what flags were given when a package was installed with homebrew?

For example, the emacs formula has an absurd number of flags. If I did

brew install emacs --with-glib --with-librsvg

I would like to later determine that for the homebrew installation of emacs I gave the flags --with-glib --with-librsvg and not any other flags.

Test case with lua package:

Before installing the package, info shows all options.

$ brew info lua
lua: stable 5.2.3 (bottled)
http://www.lua.org/
Not installed
From: https://github.com/Homebrew/homebrew/blob/master/Library/Formula/lua.rb
==> Options
--universal
    Build a universal binary
--with-completion
    Enables advanced readline support
--without-sigaction
    Revert to ANSI signal instead of improved POSIX sigaction

I install the package with just the --with-completion flag.

$ brew install lua --with-completion
==> Downloading http://www.lua.org/ftp/lua-5.2.3.tar.gz
######################################################################## 100.0%
==> Downloading http://luajit.org/patches/lua-5.2.0-advanced_readline.patch
######################################################################## 100.0%
==> Downloading http://lua-users.org/files/wiki_insecure/power_patches/5.2/lua-5
######################################################################## 100.0%
==> Patching
patching file Makefile
patching file src/Makefile
patching file src/lua.c
Hunk #1 succeeded at 231 (offset -5 lines).
Hunk #2 succeeded at 559 (offset -4 lines).
Hunk #3 succeeded at 575 (offset -4 lines).
patching file src/lua.c
==> make macosx INSTALL_TOP=/usr/local/Cellar/lua/5.2.3_1 INSTALL_MAN=/usr/local
==> make install INSTALL_TOP=/usr/local/Cellar/lua/5.2.3_1 INSTALL_MAN=/usr/loca
🍺  /usr/local/Cellar/lua/5.2.3_1: 13 files, 312K, built in 6 seconds

After installing the package, info shows all options, including those I did not use. The command does acknowledge that the package was built from source and not poured from a bottle.

$ brew info lua
lua: stable 5.2.3 (bottled)
http://www.lua.org/
/usr/local/Cellar/lua/5.2.3_1 (13 files, 312K) *
  Built from source with: --with-completion
From: https://github.com/Homebrew/homebrew/blob/master/Library/Formula/lua.rb
==> Options
--universal
    Build a universal binary
--with-completion
    Enables advanced readline support
--without-sigaction
    Revert to ANSI signal instead of improved POSIX sigaction

Answer 1

When a package is built from source the flags that were used to build are shown when you do brew info <package>.

In this case: brew info emacs | grep "Built from source"

Answer 2

There is a file in /usr/local/Cellar underneath each package that is called INSTALL_RECEIPT.json, e.g. for gawk:

/usr/local/Cellar/gawk/4.1.3/INSTALL_RECEIPT.json

that defines how the package was installed. I think the correct way to access it is with

brew info --json=v1 <packagename>

e.g.

brew info --json=v1 gnuplot

That spews out loads of stuff, but if you send it through jq (JSON Processor - handily available via homebrew) you can select out the options you used to install the package like this (checking the gnuplot package):

brew info --json=v1 gnuplot | jq '.[].installed[0].used_options'
[
    "--with-qt"
]

which tells me I installed gnuplot using:

brew install --with-qt gnuplot 

Answer 3

Another useful tool is homebrew-bundler. Once installed via brew tap Homebrew/bundle, you can run brew bundle dump and it will create a Brewfile file that lists all of the packages you have installed along with any additional args used to install them.

Answer 4

Here's a little bash function that returns the flags irrespective of if package was built from source or not.

function brew_options()
{
    [ "$#" -ne 1 ] && >&2 echo -e "$FUNCNAME requires only 1 option, the package name" && return 1

    local item=$1
    local opts

    ## Check if package installed
    [ -n "$(brew ls --versions $item)" ] || ( >&2 echo -e "$item is not installed" && return 1 )

    set -o pipefail

    ## Get options if built from source
    if ! opts="$(brew info $item | grep 'Built from source with:' | sed 's/^[ \t]*Built from source with:/ /g; s/\,/ /g')" ; then
        # If not built from source, get options from brew metadata
        opts="$(brew info --json=v1 $item | jq -ec '.[].installed[0].used_options' | awk '{print substr($0, 2, length($0) - 2)}' | sed 's/,/ /g;s/"//g')"
    fi

    ## If we're able to get options and its just not spaces echo it 
    if [ "$?" -eq 0 ] && [[ ! -z "${opts// }" ]]; then
        echo "$opts"
    fi

    set +o pipefail

}

To use this bash function within a bash script write

 brew_options PKGNAME

where PKGNAME is the desired homebrew package name. You can also iterate through all installed homebrew packages within a bash script as

 # Command to generate install script
 PKGS=$(brew list)

 # iterate through all packges
 for PKG in $PKGS; do

   echo $PKG `brew_options $PKG`

 done

.