# Force UTF-8 to avoid encoding issues for users with broken locale settings.
if [[ "$(locale charmap 2>/dev/null)" != "UTF-8" ]]
then
  export LC_ALL="en_US.UTF-8"
fi

# USER isn't always set so provide a fall back for `brew` and subprocesses.
export USER=${USER:-`id -un`}

# Where we store built products; a Cellar in HOMEBREW_PREFIX (often /usr/local
# for bottles) unless there's already a Cellar in HOMEBREW_REPOSITORY.
if [[ -d "$HOMEBREW_REPOSITORY/Cellar" ]]
then
  HOMEBREW_CELLAR="$HOMEBREW_REPOSITORY/Cellar"
else
  HOMEBREW_CELLAR="$HOMEBREW_PREFIX/Cellar"
fi

case "$*" in
  --prefix)            echo "$HOMEBREW_PREFIX"; exit 0 ;;
  --cellar)            echo "$HOMEBREW_CELLAR"; exit 0 ;;
  --repository|--repo) echo "$HOMEBREW_REPOSITORY"; exit 0 ;;
esac

# A depth of 1 means this command was directly invoked by a user.
# Higher depths mean this command was invoked by another Homebrew command.
export HOMEBREW_COMMAND_DEPTH=$((HOMEBREW_COMMAND_DEPTH + 1))

ohai() {
  if [[ -n "$HOMEBREW_COLOR" || (-t 1 && -z "$HOMEBREW_NO_COLOR") ]] # check whether stdout is a tty.
  then
    echo -e "\\033[34m==>\\033[0m \\033[1m$*\\033[0m" # blue arrow and bold text
  else
    echo "==> $*"
  fi
}

onoe() {
  if [[ -n "$HOMEBREW_COLOR" || (-t 2 && -z "$HOMEBREW_NO_COLOR") ]] # check whether stderr is a tty.
  then
    echo -ne "\\033[4;31mError\\033[0m: " >&2 # highlight Error with underline and red color
  else
    echo -n "Error: " >&2
  fi
  if [[ $# -eq 0 ]]
  then
    cat >&2
  else
    echo "$*" >&2
  fi
}

odie() {
  onoe "$@"
  exit 1
}

safe_cd() {
  cd "$@" >/dev/null || odie "Error: failed to cd to $*!"
}

brew() {
  "$HOMEBREW_BREW_FILE" "$@"
}

git() {
  "$HOMEBREW_LIBRARY/Homebrew/shims/scm/git" "$@"
}

numeric() {
  # Condense the exploded argument into a single return value.
  # shellcheck disable=SC2086,SC2183
  printf "%01d%02d%02d%03d" ${1//[.rc]/ } 2>/dev/null
}

HOMEBREW_VERSION="$(git -C "$HOMEBREW_REPOSITORY" describe --tags --dirty --abbrev=7 2>/dev/null)"
HOMEBREW_USER_AGENT_VERSION="$HOMEBREW_VERSION"
if [[ -z "$HOMEBREW_VERSION" ]]
then
  HOMEBREW_VERSION=">=2.2.0 (shallow or no git repository)"
  HOMEBREW_USER_AGENT_VERSION="2.X.Y"
fi

if [[ "$HOMEBREW_PREFIX" = "/" || "$HOMEBREW_PREFIX" = "/usr" ]]
then
  # it may work, but I only see pain this route and don't want to support it
  odie "Cowardly refusing to continue at this prefix: $HOMEBREW_PREFIX"
fi

HOMEBREW_SYSTEM="$(uname -s)"
case "$HOMEBREW_SYSTEM" in
  Darwin) HOMEBREW_MACOS="1" ;;
  Linux)  HOMEBREW_LINUX="1" ;;
esac

if [[ -n "$HOMEBREW_FORCE_BREWED_CURL" &&
      -x "$HOMEBREW_PREFIX/opt/curl/bin/curl" ]] &&
         "$HOMEBREW_PREFIX/opt/curl/bin/curl" --version >/dev/null
then
  HOMEBREW_CURL="$HOMEBREW_PREFIX/opt/curl/bin/curl"
elif [[ -n "$HOMEBREW_DEVELOPER" && -x "$HOMEBREW_CURL_PATH" ]]
then
  HOMEBREW_CURL="$HOMEBREW_CURL_PATH"
else
  HOMEBREW_CURL="curl"
fi

if [[ -n "$HOMEBREW_FORCE_BREWED_GIT" &&
      -x "$HOMEBREW_PREFIX/opt/git/bin/git" ]] &&
         "$HOMEBREW_PREFIX/opt/git/bin/git" --version >/dev/null
then
  HOMEBREW_GIT="$HOMEBREW_PREFIX/opt/git/bin/git"
elif [[ -n "$HOMEBREW_DEVELOPER" && -x "$HOMEBREW_GIT_PATH" ]]
then
  HOMEBREW_GIT="$HOMEBREW_GIT_PATH"
else
  HOMEBREW_GIT="git"
fi

if [[ -n "$HOMEBREW_MACOS" ]]
then
  HOMEBREW_PROCESSOR="$(uname -p)"
  HOMEBREW_PRODUCT="Homebrew"
  HOMEBREW_SYSTEM="Macintosh"
  # This is i386 even on x86_64 machines
  [[ "$HOMEBREW_PROCESSOR" = "i386" ]] && HOMEBREW_PROCESSOR="Intel"
  HOMEBREW_MACOS_VERSION="$(/usr/bin/sw_vers -productVersion)"
  HOMEBREW_OS_VERSION="macOS $HOMEBREW_MACOS_VERSION"
  # Don't change this from Mac OS X to match what macOS itself does in Safari on 10.12
  HOMEBREW_OS_USER_AGENT_VERSION="Mac OS X $HOMEBREW_MACOS_VERSION"

  # Intentionally set this variable by exploding another.
  # shellcheck disable=SC2086,SC2183
  printf -v HOMEBREW_MACOS_VERSION_NUMERIC "%02d%02d%02d" ${HOMEBREW_MACOS_VERSION//./ }

  # Refuse to run on pre-Yosemite
  if [[ "$HOMEBREW_MACOS_VERSION_NUMERIC" -lt "101000" ]]
  then
    printf "ERROR: Your version of macOS (%s) is too old to run Homebrew!\\n" "$HOMEBREW_MACOS_VERSION" >&2
    if [[ "$HOMEBREW_MACOS_VERSION_NUMERIC" -lt "100700" ]]
    then
      printf "         For 10.4 - 10.6 support see: https://github.com/mistydemeo/tigerbrew\\n" >&2
    fi
    printf "\\n" >&2
  fi

  # The system Git on macOS versions before Sierra is too old for some Homebrew functionality we rely on.
  HOMEBREW_MINIMUM_GIT_VERSION="2.14.3"
  if [[ "$HOMEBREW_MACOS_VERSION_NUMERIC" -lt "101200" ]]
  then
    HOMEBREW_FORCE_BREWED_GIT="1"
  fi

  HOMEBREW_DEFAULT_CACHE="${HOME}/Library/Caches/Homebrew"
  HOMEBREW_DEFAULT_LOGS="${HOME}/Library/Logs/Homebrew"
  HOMEBREW_DEFAULT_TEMP="/private/tmp"

  # Set a variable when the macOS system Ruby is new enough to avoid spawning
  # a Ruby process unnecessarily.
  if [[ "$HOMEBREW_MACOS_VERSION_NUMERIC" -lt "101500" ]]
  then
    unset HOMEBREW_MACOS_SYSTEM_RUBY_NEW_ENOUGH
  else
    # Used in ruby.sh.
    # shellcheck disable=SC2034
    HOMEBREW_MACOS_SYSTEM_RUBY_NEW_ENOUGH="1"
  fi
else
  HOMEBREW_PROCESSOR="$(uname -m)"
  HOMEBREW_PRODUCT="${HOMEBREW_SYSTEM}brew"
  [[ -n "$HOMEBREW_LINUX" ]] && HOMEBREW_OS_VERSION="$(lsb_release -sd 2>/dev/null)"
  : "${HOMEBREW_OS_VERSION:=$(uname -r)}"
  HOMEBREW_OS_USER_AGENT_VERSION="$HOMEBREW_OS_VERSION"

  # Ensure the system Curl is a version that supports modern HTTPS certificates.
  HOMEBREW_MINIMUM_CURL_VERSION="7.41.0"
  curl_version_output="$($HOMEBREW_CURL --version 2>/dev/null)"
  curl_name_and_version="${curl_version_output%% (*}"
  if [[ $(numeric "${curl_name_and_version##* }") -lt $(numeric "$HOMEBREW_MINIMUM_CURL_VERSION") ]]
  then
    if [[ -z $HOMEBREW_CURL_PATH ]]; then
      HOMEBREW_SYSTEM_CURL_TOO_OLD=1
      HOMEBREW_FORCE_BREWED_CURL=1
    else
      odie <<EOS
The version of cURL that you provided to Homebrew using HOMEBREW_CURL_PATH is too old.
Minimum required version: ${HOMEBREW_MINIMUM_CURL_VERSION}.
Your cURL version: ${curl_name_and_version##* }.
Please point Homebrew to cURL ${HOMEBREW_MINIMUM_CURL_VERSION} or newer
or unset HOMEBREW_CURL_PATH variable.
EOS
    fi
  fi

  # Ensure the system Git is at or newer than the minimum required version.
  # Git 2.7.4 is the version of git on Ubuntu 16.04 LTS (Xenial Xerus).
  HOMEBREW_MINIMUM_GIT_VERSION="2.7.0"
  git_version_output="$($HOMEBREW_GIT --version 2>/dev/null)"
  # $extra is intentionally discarded.
  # shellcheck disable=SC2034
  IFS=. read -r major minor micro build extra <<< "${git_version_output##* }"
  if [[ $(numeric "$major.$minor.$micro.$build") -lt $(numeric "$HOMEBREW_MINIMUM_GIT_VERSION") ]]
  then
    if [[ -z $HOMEBREW_GIT_PATH ]]; then
      HOMEBREW_FORCE_BREWED_GIT="1"
    else
      odie <<EOS
The version of Git that you provided to Homebrew using HOMEBREW_GIT_PATH is too old.
Minimum required version: ${HOMEBREW_MINIMUM_GIT_VERSION}.
Your Git version: $major.$minor.$micro.$build.
Please point Homebrew to Git ${HOMEBREW_MINIMUM_CURL_VERSION} or newer
or unset HOMEBREW_GIT_PATH variable.
EOS
    fi
  fi

  CACHE_HOME="${XDG_CACHE_HOME:-${HOME}/.cache}"
  HOMEBREW_DEFAULT_CACHE="${CACHE_HOME}/Homebrew"
  HOMEBREW_DEFAULT_LOGS="${CACHE_HOME}/Homebrew/Logs"
  HOMEBREW_DEFAULT_TEMP="/tmp"

  unset HOMEBREW_MACOS_SYSTEM_RUBY_NEW_ENOUGH
fi

if [[ -n "$HOMEBREW_MACOS" || -n "$HOMEBREW_FORCE_HOMEBREW_ON_LINUX" ]]
then
  HOMEBREW_BOTTLE_DEFAULT_DOMAIN="https://homebrew.bintray.com"
else
  HOMEBREW_BOTTLE_DEFAULT_DOMAIN="https://linuxbrew.bintray.com"
fi

HOMEBREW_CACHE="${HOMEBREW_CACHE:-${HOMEBREW_DEFAULT_CACHE}}"
HOMEBREW_LOGS="${HOMEBREW_LOGS:-${HOMEBREW_DEFAULT_LOGS}}"
HOMEBREW_TEMP="${HOMEBREW_TEMP:-${HOMEBREW_DEFAULT_TEMP}}"

case "$*" in
  --cache)             echo "$HOMEBREW_CACHE"; exit 0 ;;
esac

HOMEBREW_USER_AGENT="$HOMEBREW_PRODUCT/$HOMEBREW_USER_AGENT_VERSION ($HOMEBREW_SYSTEM; $HOMEBREW_PROCESSOR $HOMEBREW_OS_USER_AGENT_VERSION)"
curl_version_output="$("$HOMEBREW_CURL" --version 2>/dev/null)"
curl_name_and_version="${curl_version_output%% (*}"
HOMEBREW_USER_AGENT_CURL="$HOMEBREW_USER_AGENT ${curl_name_and_version// //}"

# Declared in bin/brew
export HOMEBREW_BREW_FILE
export HOMEBREW_PREFIX
export HOMEBREW_REPOSITORY
export HOMEBREW_LIBRARY

# Declared in brew.sh
export HOMEBREW_VERSION
export HOMEBREW_DEFAULT_CACHE
export HOMEBREW_CACHE
export HOMEBREW_DEFAULT_LOGS
export HOMEBREW_LOGS
export HOMEBREW_DEFAULT_TEMP
export HOMEBREW_TEMP
export HOMEBREW_CELLAR
export HOMEBREW_SYSTEM
export HOMEBREW_CURL
export HOMEBREW_SYSTEM_CURL_TOO_OLD
export HOMEBREW_GIT
export HOMEBREW_MINIMUM_GIT_VERSION
export HOMEBREW_PROCESSOR
export HOMEBREW_PRODUCT
export HOMEBREW_OS_VERSION
export HOMEBREW_MACOS_VERSION
export HOMEBREW_MACOS_VERSION_NUMERIC
export HOMEBREW_USER_AGENT
export HOMEBREW_USER_AGENT_CURL
export HOMEBREW_BOTTLE_DEFAULT_DOMAIN

if [[ -n "$HOMEBREW_MACOS" && -x "/usr/bin/xcode-select" ]]
then
  XCODE_SELECT_PATH=$('/usr/bin/xcode-select' --print-path 2>/dev/null)
  if [[ "$XCODE_SELECT_PATH" = "/" ]]
  then
    odie <<EOS
Your xcode-select path is currently set to '/'.
This causes the 'xcrun' tool to hang, and can render Homebrew unusable.
If you are using Xcode, you should:
  sudo xcode-select -switch /Applications/Xcode.app
Otherwise, you should:
  sudo rm -rf /usr/share/xcode-select
EOS
  fi

  # Don't check xcrun if Xcode and the CLT aren't installed, as that opens
  # a popup window asking the user to install the CLT
  if [[ -n "$XCODE_SELECT_PATH" ]]
  then
    XCRUN_OUTPUT="$(/usr/bin/xcrun clang 2>&1)"
    XCRUN_STATUS="$?"

    if [[ "$XCRUN_STATUS" -ne 0 && "$XCRUN_OUTPUT" = *license* ]]
    then
      odie <<EOS
You have not agreed to the Xcode license. Please resolve this by running:
  sudo xcodebuild -license accept
EOS
    fi
  fi
fi

# Many Pathname operations use getwd when they shouldn't, and then throw
# odd exceptions. Reduce our support burden by showing a user-friendly error.
if [[ ! -d "$(pwd)" ]]
then
  odie "The current working directory doesn't exist, cannot proceed."
fi

if [[ "$1" = -v ]]
then
  # Shift the -v to the end of the parameter list
  shift
  set -- "$@" -v
fi

for arg in "$@"
do
  if [[ $arg = "--help" || $arg = "-h" || $arg = "--usage" || $arg = "-?" ]]
  then
    export HOMEBREW_HELP="1"
    break
  fi
done

HOMEBREW_ARG_COUNT="$#"
HOMEBREW_COMMAND="$1"
shift
case "$HOMEBREW_COMMAND" in
  ls)          HOMEBREW_COMMAND="list" ;;
  homepage)    HOMEBREW_COMMAND="home" ;;
  -S)          HOMEBREW_COMMAND="search" ;;
  up)          HOMEBREW_COMMAND="update" ;;
  ln)          HOMEBREW_COMMAND="link" ;;
  instal)      HOMEBREW_COMMAND="install" ;; # gem does the same
  uninstal)    HOMEBREW_COMMAND="uninstall" ;;
  rm)          HOMEBREW_COMMAND="uninstall" ;;
  remove)      HOMEBREW_COMMAND="uninstall" ;;
  configure)   HOMEBREW_COMMAND="diy" ;;
  abv)         HOMEBREW_COMMAND="info" ;;
  dr)          HOMEBREW_COMMAND="doctor" ;;
  --repo)      HOMEBREW_COMMAND="--repository" ;;
  environment) HOMEBREW_COMMAND="--env" ;;
  --config)    HOMEBREW_COMMAND="config" ;;
  -v)          HOMEBREW_COMMAND="--version" ;;
esac

if [[ "$HOMEBREW_COMMAND" = "cask" ]]
then
  HOMEBREW_CASK_COMMAND="$1"

  case "$HOMEBREW_CASK_COMMAND" in
    instal) HOMEBREW_CASK_COMMAND="install" ;; # gem does the same
  esac
fi

if [[ "$HOMEBREW_COMMAND" = "audit" || "$HOMEBREW_COMMAND" = "style" ]]
then
  export HOMEBREW_INSTALL_BUNDLER_GEMS_FIRST="1"
fi

# Set HOMEBREW_DEV_CMD_RUN for users who have run a development command.
# This makes them behave like HOMEBREW_DEVELOPERs for brew update.
if [[ -z "$HOMEBREW_DEVELOPER" ]]
then
  export HOMEBREW_GIT_CONFIG_FILE="$HOMEBREW_REPOSITORY/.git/config"
  HOMEBREW_GIT_CONFIG_DEVELOPERMODE="$(git config --file="$HOMEBREW_GIT_CONFIG_FILE" --get homebrew.devcmdrun 2>/dev/null)"
  if [[ "$HOMEBREW_GIT_CONFIG_DEVELOPERMODE" = "true" ]]
  then
    export HOMEBREW_DEV_CMD_RUN="1"
  fi

  # Don't allow non-developers to customise Ruby warnings.
  unset HOMEBREW_RUBY_WARNINGS

  # Disable Ruby options we don't need. RubyGems provides a decent speedup.
  RUBY_DISABLE_OPTIONS="--disable=gems,did_you_mean,rubyopt"
else
  # Don't disable did_you_mean for developers as it's useful.
  RUBY_DISABLE_OPTIONS="--disable=gems,rubyopt"
fi

if [[ -z "$HOMEBREW_RUBY_WARNINGS" ]]
then
  export HOMEBREW_RUBY_WARNINGS="-W0"
fi

if [[ -z "$HOMEBREW_BOTTLE_DOMAIN" ]]
then
  export HOMEBREW_BOTTLE_DOMAIN="$HOMEBREW_BOTTLE_DEFAULT_DOMAIN"
fi

export HOMEBREW_BREW_DEFAULT_GIT_REMOTE="https://github.com/Homebrew/brew"
if [[ -z "$HOMEBREW_BREW_GIT_REMOTE" ]]
then
  HOMEBREW_BREW_GIT_REMOTE="$HOMEBREW_BREW_DEFAULT_GIT_REMOTE"
fi
export HOMEBREW_BREW_GIT_REMOTE

if [[ -n "$HOMEBREW_MACOS" ]] || [[ -n "$HOMEBREW_FORCE_HOMEBREW_ON_LINUX" ]]
then
  HOMEBREW_CORE_DEFAULT_GIT_REMOTE="https://github.com/Homebrew/homebrew-core"
else
  HOMEBREW_CORE_DEFAULT_GIT_REMOTE="https://github.com/Homebrew/linuxbrew-core"
fi
export HOMEBREW_CORE_DEFAULT_GIT_REMOTE

if [[ -z "$HOMEBREW_CORE_GIT_REMOTE" ]]
then
  HOMEBREW_CORE_GIT_REMOTE="$HOMEBREW_CORE_DEFAULT_GIT_REMOTE"
fi
export HOMEBREW_CORE_GIT_REMOTE

if [[ -f "$HOMEBREW_LIBRARY/Homebrew/cmd/$HOMEBREW_COMMAND.sh" ]]
then
  HOMEBREW_BASH_COMMAND="$HOMEBREW_LIBRARY/Homebrew/cmd/$HOMEBREW_COMMAND.sh"
elif [[ -f "$HOMEBREW_LIBRARY/Homebrew/dev-cmd/$HOMEBREW_COMMAND.sh" ]]
then
  if [[ -z "$HOMEBREW_DEVELOPER" ]]
  then
    git config --file="$HOMEBREW_GIT_CONFIG_FILE" --replace-all homebrew.devcmdrun true 2>/dev/null
    export HOMEBREW_DEV_CMD_RUN="1"
  fi
  HOMEBREW_BASH_COMMAND="$HOMEBREW_LIBRARY/Homebrew/dev-cmd/$HOMEBREW_COMMAND.sh"
fi

check-run-command-as-root() {
  [[ "$(id -u)" = 0 ]] || return

  # Allow Azure Pipelines/Docker/Concourse/Kubernetes to do everything as root (as it's normal there)
  [[ -f /proc/1/cgroup ]] && grep -E "azpl_job|docker|garden|kubepods" -q /proc/1/cgroup && return

  # Homebrew Services may need `sudo` for system-wide daemons.
  [[ "$HOMEBREW_COMMAND" = "services" ]] && return

  # It's fine to run this as root as it's not changing anything.
  [[ "$HOMEBREW_COMMAND" = "--prefix" ]] && return

  odie <<EOS
Running Homebrew as root is extremely dangerous and no longer supported.
As Homebrew does not drop privileges on installation you would be giving all
build scripts full access to your system.
EOS
}
check-run-command-as-root

check-prefix-is-not-tmpdir() {
  [[ -z "${HOMEBREW_MACOS}" ]] && return

  if [[ "${HOMEBREW_PREFIX}" = "${HOMEBREW_TEMP}"* ]]
  then
    odie <<EOS
Your HOMEBREW_PREFIX is in the Homebrew temporary directory, which Homebrew
uses to store downloads and builds. You can resolve this by installing Homebrew to
either the standard prefix (/usr/local) or to a non-standard prefix that is not
in the Homebrew temporary directory.
EOS
  fi
}
check-prefix-is-not-tmpdir

if [[ "$HOMEBREW_PREFIX" = "/usr/local" &&
      "$HOMEBREW_PREFIX" != "$HOMEBREW_REPOSITORY" &&
      "$HOMEBREW_CELLAR" = "$HOMEBREW_REPOSITORY/Cellar" ]]
then
  cat >&2 <<EOS
Warning: your HOMEBREW_PREFIX is set to /usr/local but HOMEBREW_CELLAR is set
to $HOMEBREW_CELLAR. Your current HOMEBREW_CELLAR location will stop
you being able to use all the binary packages (bottles) Homebrew provides. We
recommend you move your HOMEBREW_CELLAR to /usr/local/Cellar which will get you
access to all bottles."
EOS
fi

# Don't need shellcheck to follow this `source`.
# shellcheck disable=SC1090
source "$HOMEBREW_LIBRARY/Homebrew/utils/analytics.sh"
setup-analytics

# Let user know we're still updating Homebrew if brew update --preinstall
# exceeds 3 seconds.
update-preinstall-timer() {
  sleep 3
  echo 'Updating Homebrew...' >&2
}

update-preinstall() {
  [[ -z "$HOMEBREW_HELP" ]] || return
  [[ -z "$HOMEBREW_NO_AUTO_UPDATE" ]] || return
  [[ -z "$HOMEBREW_AUTO_UPDATING" ]] || return
  [[ -z "$HOMEBREW_UPDATE_PREINSTALL" ]] || return
  [[ -z "$HOMEBREW_AUTO_UPDATE_CHECKED" ]] || return

  # If we've checked for updates, we don't need to check again.
  export HOMEBREW_AUTO_UPDATE_CHECKED="1"

  if [[ "$HOMEBREW_COMMAND" = "cask" ]]
  then
    if [[ "$HOMEBREW_CASK_COMMAND" != "upgrade" && $HOMEBREW_ARG_COUNT -lt 3 ]]
    then
      return
    fi
  elif [[ "$HOMEBREW_COMMAND" != "upgrade" && $HOMEBREW_ARG_COUNT -lt 2 ]]
  then
    return
  fi

  if [[ "$HOMEBREW_COMMAND" = "install" || "$HOMEBREW_COMMAND" = "upgrade" ||
        "$HOMEBREW_COMMAND" = "bump-formula-pr" ||
        "$HOMEBREW_COMMAND" = "tap" && $HOMEBREW_ARG_COUNT -gt 1 ||
        "$HOMEBREW_CASK_COMMAND" = "install" || "$HOMEBREW_CASK_COMMAND" = "upgrade" ]]
  then
    export HOMEBREW_AUTO_UPDATING="1"

    # Skip auto-update if the cask/core tap has been updated in the
    # last $HOMEBREW_AUTO_UPDATE_SECS.
    if [[ "$HOMEBREW_COMMAND" = "cask" ]]
    then
      tap_fetch_head="$HOMEBREW_LIBRARY/Taps/homebrew/homebrew-cask/.git/FETCH_HEAD"
    else
      tap_fetch_head="$HOMEBREW_LIBRARY/Taps/homebrew/homebrew-core/.git/FETCH_HEAD"
    fi
    if [[ -f "$tap_fetch_head" &&
          -n "$(find "$tap_fetch_head" -type f -mtime -"${HOMEBREW_AUTO_UPDATE_SECS}"s 2>/dev/null)" ]]
    then
      return
    fi

    if [[ -z "$HOMEBREW_VERBOSE" ]]
    then
      update-preinstall-timer &
      timer_pid=$!
    fi

    brew update --preinstall

    if [[ -n "$timer_pid" ]]
    then
      kill "$timer_pid" 2>/dev/null
      wait "$timer_pid" 2>/dev/null
    fi

    unset HOMEBREW_AUTO_UPDATING

    # exec a new process to set any new environment variables.
    exec "$HOMEBREW_BREW_FILE" "$@"
  fi
}

if [[ -n "$HOMEBREW_BASH_COMMAND" ]]
then
  # source rather than executing directly to ensure the entire file is read into
  # memory before it is run. This makes running a Bash script behave more like
  # a Ruby script and avoids hard-to-debug issues if the Bash script is updated
  # at the same time as being run.
  #
  # Don't need shellcheck to follow this `source`.
  # shellcheck disable=SC1090
  source "$HOMEBREW_BASH_COMMAND"
  { update-preinstall "$@"; "homebrew-$HOMEBREW_COMMAND" "$@"; exit $?; }
else
  # Don't need shellcheck to follow this `source`.
  # shellcheck disable=SC1090
  source "$HOMEBREW_LIBRARY/Homebrew/utils/ruby.sh"
  setup-ruby-path

  # Unshift command back into argument list (unless argument list was empty).
  [[ "$HOMEBREW_ARG_COUNT" -gt 0 ]] && set -- "$HOMEBREW_COMMAND" "$@"
  { update-preinstall "$@"; exec "$HOMEBREW_RUBY_PATH" $HOMEBREW_RUBY_WARNINGS "$RUBY_DISABLE_OPTIONS" "$HOMEBREW_LIBRARY/Homebrew/brew.rb" "$@"; }
fi
