如何在gitlab-ci

Question

如何使用shell在gitlab-ci中安装brew

# - ruby -e "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install)"  
# - sh -c "$(curl -fsSL https://raw.githubusercontent.com/Linuxbrew/install/master/install.sh)"

# - curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install
- curl -fsSL https://raw.githubusercontent.com/Linuxbrew/install/master/install
- PATH=/usr/local/bin:$PATH

这无法成功安装

这是我的.gitlab-ci.yml文件代码

stages:
  - build
  - archive

before_script:
- gem install cocoapods
# - pod install


build_project:
  stage: build
  script: 
    # - ruby -e "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install)"  
    # - sh -c "$(curl -fsSL https://raw.githubusercontent.com/Linuxbrew/install/master/install.sh)"


    # - curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install
    - curl -fsSL https://raw.githubusercontent.com/Linuxbrew/install/master/install
    - PATH=/usr/local/bin:$PATH

    - brew install xctool
    - xctool -project cicdios.xcodeproj -scheme cicdios clean
    - xctool -project cicdios.xcodeproj -scheme cicdios test -test-sdk iphonesimulator9.3

archive_project:
  stage: archive
  script: 
    - xctool -project cicdios.xcodeproj -scheme cicdios archive -archivePath build/cicdios
    - xcodebuild -exportArchive -exportFormat ipa -archivePath "build/cicdios.xcarchive" -exportPath "build/cicdios.ipa"
  only: 
    - master
  artifacts:
    paths:
      - build/cicdios.ipa

我想在gitlab-ci中构建项目，但是这个yml需要安装xctool，因此如果我安装xctool必须安装brew，但是我不知道如何在其中安装brew