仅列出rbenv的宝石

Question

每当我运行gem list时，它都会列出所有宝石，包括系统中的默认宝石。我该如何列出通过rbenv安装的gem？

我的宝石环境：

RubyGems Environment:
  - RUBYGEMS VERSION: 2.7.6
  - RUBY VERSION: 2.5.1 (2018-03-29 patchlevel 57) [x86_64-darwin17]
  - INSTALLATION DIRECTORY: /Users/justme/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0
  - USER INSTALLATION DIRECTORY: /Users/justme/.gem/ruby/2.5.0
  - RUBY EXECUTABLE: /Users/justme/.rbenv/versions/2.5.1/bin/ruby
  - EXECUTABLE DIRECTORY: /Users/justme/.rbenv/versions/2.5.1/bin
  - SPEC CACHE DIRECTORY: /Users/justme/.gem/specs
  - SYSTEM CONFIGURATION DIRECTORY: /Users/justme/.rbenv/versions/2.5.1/etc
  - RUBYGEMS PLATFORMS:
    - ruby
    - x86_64-darwin-17
  - GEM PATHS:
     - /Users/justme/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0
     - /Users/justme/.gem/ruby/2.5.0
  - GEM CONFIGURATION:
     - :update_sources => true
     - :verbose => true
     - :backtrace => false
     - :bulk_threshold => 1000
  - REMOTE SOURCES:
     - https://rubygems.org/
  - SHELL PATH:
     - /Users/justme/.rbenv/versions/2.5.1/bin
     - /usr/local/Cellar/rbenv/1.1.1/libexec
     - /Users/justme/.rbenv/shims
     - /usr/local/bin
     - /usr/bin
     - /bin
     - /usr/sbin
     - /sbin