steps:
  # Install Node.js
  - task: NodeTool@0
    inputs:
      versionSpec: "12.0.0"
    displayName: "Install a fixed version of Node"
  # Install Go
  - task: GoTool@0
    inputs:
      versionSpec: "1.10"
    displayName: "Install a fixed version of Go"

  # Because the Pipelines agent updates are out of sync, we can't install 3.6.9
  # with PythonTool on macOS

  # Install Python
  - task: UsePythonVersion@0
    inputs:
      versionSpec: "3.6.9"
    displayName: "Install a fixed version of Python"
    condition: not(eq(variables['Agent.OS'], 'Darwin'))
  # Install Python (macOS)
  - script: |
      echo "##vso[task.setvariable variable=PYTHON_VERSION;]3.6.9"
      echo "##vso[task.setvariable variable=PYENV_ROOT;]$HOME/.pyenv"
    condition: eq(variables['Agent.OS'], 'Darwin')
  - script: |
      curl https://pyenv.run | bash
      echo "##vso[task.setvariable variable=PATH;]$PYENV_ROOT/bin:$PYENV_ROOT/shims:$PATH"
    condition: eq(variables['Agent.OS'], 'Darwin')
  - script: |
      eval "$(pyenv init -)"
      pyenv install $PYTHON_VERSION
      pyenv global $PYTHON_VERSION
    condition: eq(variables['Agent.OS'], 'Darwin')
    displayName: "Install a fixed version of Python"