初始化pod文件失败

$ pod init

-bash: /usr/local/bin/pod: /System/Library/Frameworks/Ruby.framework/Versions/2.0/usr/bin/ruby: bad interpreter: No such file or directory

重新下载cocoapods失败

$sudo gem install cocoapods

Fetching: concurrent-ruby-1.0.5.gem (100%)
Successfully installed concurrent-ruby-1.0.5
Fetching: i18n-0.9.1.gem (100%)
Successfully installed i18n-0.9.1
Fetching: thread_safe-0.3.6.gem (100%)
Successfully installed thread_safe-0.3.6
Fetching: tzinfo-1.2.4.gem (100%)
Successfully installed tzinfo-1.2.4
Fetching: activesupport-4.2.10.gem (100%)
Successfully installed activesupport-4.2.10
Fetching: nap-1.1.0.gem (100%)
Successfully installed nap-1.1.0
Fetching: fuzzy_match-2.0.4.gem (100%)
Successfully installed fuzzy_match-2.0.4
Fetching: cocoapods-core-1.4.0.gem (100%)
Successfully installed cocoapods-core-1.4.0
Fetching: claide-1.0.2.gem (100%)
Successfully installed claide-1.0.2
Fetching: cocoapods-deintegrate-1.0.2.gem (100%)
Successfully installed cocoapods-deintegrate-1.0.2
Fetching: cocoapods-downloader-1.1.3.gem (100%)
Successfully installed cocoapods-downloader-1.1.3
Fetching: cocoapods-plugins-1.0.0.gem (100%)
Successfully installed cocoapods-plugins-1.0.0
Fetching: cocoapods-search-1.0.0.gem (100%)
Successfully installed cocoapods-search-1.0.0
Fetching: cocoapods-stats-1.0.0.gem (100%)
Successfully installed cocoapods-stats-1.0.0
Fetching: netrc-0.11.0.gem (100%)
Successfully installed netrc-0.11.0
Fetching: cocoapods-trunk-1.3.0.gem (100%)
Successfully installed cocoapods-trunk-1.3.0
Fetching: cocoapods-try-1.1.0.gem (100%)
Successfully installed cocoapods-try-1.1.0
Fetching: molinillo-0.6.4.gem (100%)
Successfully installed molinillo-0.6.4
Fetching: CFPropertyList-2.3.6.gem (100%)
Successfully installed CFPropertyList-2.3.6
Fetching: colored2-3.1.2.gem (100%)
Successfully installed colored2-3.1.2
Fetching: nanaimo-0.2.3.gem (100%)
Successfully installed nanaimo-0.2.3
Fetching: xcodeproj-1.5.4.gem (100%)
ERROR: While executing gem ... (TypeError)
no implicit conversion of nil into String
me:te JunJie$ sudo gem install -n /usr/local/bin cocoapods --pre
ERROR: While executing gem ... (TypeError)
no implicit conversion of nil into String

查看源

$gem sources -l

*** CURRENT SOURCES ***

添加源

$gem source -a https://gems.ruby-china.org/

https://gems.ruby-china.org/ added to sources

更新gem

$sudo gem update --system

Updating rubygems-update
Fetching: rubygems-update-2.6.14.gem (100%)
Successfully installed rubygems-update-2.6.14
Parsing documentation for rubygems-update-2.6.14
Installing ri documentation for rubygems-update-2.6.14
Installing darkfish documentation for rubygems-update-2.6.14
Done installing documentation for rubygems-update after 43 seconds
Parsing documentation for rubygems-update-2.6.14
Done installing documentation for rubygems-update after 0 seconds
Installing RubyGems 2.6.14
RubyGems 2.6.14 installed
Parsing documentation for rubygems-2.6.14
Installing ri documentation for rubygems-2.6.14

=== 2.6.14 / 2017-10-09

Security fixes:

• Whitelist classes and symbols that are in loaded YAML.
  See CVE-2017-0903 for full details.
  Fix by Aaron Patterson.

=== 2.6.13 / 2017-08-27

Security fixes:

• Fix a DNS request hijacking vulnerability.
  Fix by Samuel Giddins.
• Fix an ANSI escape sequence vulnerability.
  Fix by Evan Phoenix.
• Fix a DOS vulernerability in the query command.
  Fix by Samuel Giddins.
• Fix a vulnerability in the gem installer that allowed
  a malicious gem to overwrite arbitrary files.
  Fix by Samuel Giddins.

=== 2.6.12 / 2017-04-30

Bug fixes:

• Fix test_self_find_files_with_gemfile to sort expected files. Pull
  request #1880 by Kazuaki Matsuo.
• Fix issue for MinGW / MSYS2 builds and testing. Pull request #1879 by
  MSP-Greg.
• Fix gem open to open highest version number rather than lowest. Pull
  request #1877 by Tim Pope.
• Add a test for requiring a default spec as installed by the ruby
  installer. Pull request #1899 by Samuel Giddins.
• Fix broken --exact parameter to gem command. Pull request #1873 by Jason
  Frey.
• [Installer] Generate backwards-compatible binstubs. Pull request #1904
  by Samuel Giddins.
• Fix pre-existing source recognition on add action. Pull request #1883 by
  Jonathan Claudius.
• Prevent negative IDs in output of #inspect. Pull request #1908 by Vít
  Ondruch.
• Allow Gem.finish_resolve to respect already-activated specs. Pull
  request #1910 by Samuel Giddins.

=== 2.6.11 / 2017-03-16

Bug fixes:

• Fixed broken tests on ruby-head. Pull request #1841 by
  SHIBATA Hiroshi.
• Update vendored Molinillo to 0.5.7. Pull request #1859 by Samuel
  Giddins.
• Avoid activating Ruby 2.5 default gems when possible. Pull request #1843
  by Samuel Giddins.
• Use improved resolver sorting algorithm. Pull request #1856 by
  Samuel Giddins.

=== 2.6.10 / 2017-01-23

Bug fixes:

• Fix require calling the wrong gem method when it is overridden.
  Pull request #1822 by Samuel Giddins.

=== 2.6.9 / 2017-01-20

Bug fixes:

• Allow initializing versions with empty strings. Pull request #1767 by
  Luis Sagastume.
• Fix TypeError on 2.4. Pull request #1788 by Nobuyoshi Nakada.
• Don't output mkmf.log message if compilation didn't fail. Pull request

  1808 by Jeremy Evans.

• Fixed broken links and overzealous URL encoding in gem server. Pull
  request #1809 by Nicole Orchard.
• Update vendored Molinillo to 0.5.5. Pull request #1812 by Samuel
  Giddins.
• RakeBuilder: avoid frozen string issue. Pull request #1819 by Olle
  Jonsson.

=== 2.6.8 / 2016-10-29

Bug fixes:

• Improve SSL verification failure message. Pull request #1751
  by Eric Hodel.
• Ensure to_spec falls back on prerelease specs. Pull request

  1755 by André Arko.

• Update vendored Molinillo to 0.5.3. Pull request #1763 by
  Samuel Giddins.

=== 2.6.7 / 2016-09-26

Bug fixes:

• Install native extensions in the correct location when using the
  --user-install flag. Pull request #1683 by Noah Kantrowitz.
• When calling Gem.sources, load sources from configuration
  if present, else use the default sources. Pull request #1699
  by Luis Sagastume.
• Fail gracefully when attempting to redirect without a Location.
  Pull request #1711 by Samuel Giddins.
• Update vendored Molinillo to 0.5.1. Pull request #1714 by
  Samuel Giddins.

=== 2.6.6 / 2016-06-22

Bug fixes:

• Sort installed versions to make sure we install the latest version when
  running gem update --system. As a one-time fix, run
  gem update --system=2.6.6. Pull request #1601 by David Radcliffe.

=== 2.6.5 / 2016-06-21

Minor enhancements:

• Support for unified Integer in Ruby 2.4. Pull request #1618
  by SHIBATA Hiroshi.
• Update vendored Molinillo to 0.5.0 for performance improvements.
  Pull request #1638 by Samuel Giddins.

Bug fixes:

• Raise an explicit error if Signer#sign is called with no certs. Pull
  request #1605 by Daniel Berger.
• Update update_bundled_ca_certificates utility script for directory
  nesting. Pull request #1583 by James Wen.
• Fix broken symlink support in tar writer (+ fix broken test). Pull
  request #1578 by Cezary Baginski.
• Remove extension directory before (re-)installing. Pull request #1576
  by Jeremy Hinegardner.
• Regenerate test CA certificates with appropriate extensions. Pull
  request #1611 by rhenium.
• Rubygems does not terminate on failed file lock when not superuser. Pull
  request #1582 by Ellen Marie Dash.
• Fix tar headers with a 101 character name. Pull request #1612 by Paweł
  Tomulik.
• Add Gem.platform_defaults to allow implementations to override defaults.
  Pull request #1644 by Charles Oliver Nutter.
• Run Bundler tests on TravisCI. Pull request #1650 by Samuel Giddins.

=== 2.6.4 / 2016-04-26

Minor enhancements:

• Use Gem::Util::NULL_DEVICE instead of hard coded strings. Pull request #1588
  by Chris Charabaruk.
• Use File.symlink on MS Windows if supported. Pull request #1418
  by Nobuyoshi Nakada.

Bug fixes:

• Redact uri password from error output when gem fetch fails. Pull request

  1565 by Brian Fletcher.

• Suppress warnings. Pull request #1594 by Nobuyoshi Nakada.
• Escape user-supplied content served on web pages by gem server to avoid
  potential XSS vulnerabilities. Samuel Giddins.

=== 2.6.3 / 2016-04-05

Minor enhancements:

• Lazily calculate Gem::LoadError exception messages. Pull request #1550
  by Aaron Patterson.
• New fastly cert. Pull request #1548 by David Radcliffe.
• Organize and cleanup SSL certs. Pull request #1555 by James Wen.
• [RubyGems] Make deprecation message for paths= more helpful. Pull
  request #1562 by Samuel Giddins.
• Show default gems when using "gem list". Pull request #1570 by Luis
  Sagastume.

Bug fixes:

• Stub ordering should be consistent regardless of how cache is populated.
  Pull request #1552 by Aaron Patterson.
• Handle cases when the @@stubs variable contains non-stubs. Pull request

  1558 by Per Lundberg.

• Fix test on Windows for inconsistent temp path. Pull request #1554 by
  Hiroshi Shirosaki.
• Fix Gem.find_spec_for_exe picks oldest gem. Pull request #1566 by
  Shinichi Maeshima.
• [Owner] Fallback to email and userid when owner email is missing. Pull
  request #1569 by Samuel Giddins.
• [Installer] Handle nil existing executable. Pull request #1561 by Samuel
  Giddins.
• Allow two digit version numbers in the tests. Pull request #1575 by unak.

=== 2.6.2 / 2016-03-12

Bug fixes:

• Fix wrong version of gem activation for bin stub. Pull request #1527 by
  Aaron Patterson.
• Speed up gem activation failures. Pull request #1539 by Aaron Patterson.
• Fix platform sorting in the resolver. Pull request #1542 by Samuel E.
  Giddins.
• Ensure we unlock the monitor even if try_activate throws. Pull request

  1538 by Charles Oliver Nutter.

=== 2.6.1 / 2016-02-28

Bug fixes:

• Ensure default_path and home are set for paths. Pull request #1513
  by Aaron Patterson.
• Restore but deprecate support for Array values on Gem.paths=. Pull
  request #1514 by Aaron Patterson.
• Fix invalid gem file preventing gem install from working. Pull request

  1499 by Luis Sagastume.

=== 2.6.0 / 2016-02-26

Minor enhancements:

• RubyGems now defaults the gem push to the gem's "allowed_push_host"
  metadata setting. Pull request #1486 by Josh Lane.
• Update bundled Molinillo to 0.4.3. Pull request #1493 by Samuel E. Giddins.
• Add version option to gem open command. Pull request #1483 by Hrvoje
  Šimić.
• Feature/add silent flag. Pull request #1455 by Luis Sagastume.
• Allow specifying gem requirements via env variables. Pull request #1472
  by Samuel E. Giddins.

Bug fixes:

• RubyGems now stores gem push credentials under the host you signed-in for.
  Pull request #1485 by Josh Lane.
• Move coding location to first line. Pull request #1471 by SHIBATA
  Hiroshi.
• [PathSupport] Handle a regexp path separator. Pull request #1469 by
  Samuel E. Giddins.
• Clean up the PathSupport object. Pull request #1094 by Aaron Patterson.
• Join with File::PATH_SEPARATOR in Gem.use_paths. Pull request #1476 by
  Samuel E. Giddins.
• Handle when the gem home and gem path arent set in the config file. Pull
  request #1478 by Samuel E. Giddins.
• Terminate TimeoutHandler. Pull request #1479 by Nobuyoshi Nakada.
• Remove redundant cache. Pull request #1482 by Eileen M. Uchitelle.
• Freeze Gem::Version@segments instance variable. Pull request #1487 by
  Ben Dean.
• Gem cleanup is trying to uninstall gems outside GEM_HOME and reporting
  an error after it tries. Pull request #1353 by Luis Sagastume.
• Avoid duplicated sources. Pull request #1489 by Luis Sagastume.
• Better description for quiet flag. Pull request #1491 by Luis Sagastume.
• Raise error if find_by_name returns with nil. Pull request #1494 by
  Zoltán Hegedüs.
• Find_files only from loaded_gems when using gemdeps. Pull request #1277
  by Michal Papis.

=== 2.5.2 / 2016-01-31

Bug fixes:

• Fix memoization of Gem::Version#prerelease? Pull request #1125 by Matijs van
  Zuijlen.
• Handle trailing colons in GEM_PATH, by Damien Robert.
• Improve the Gemfile gemspec method, fixing #1204 and #1033. Pull request

  1276 by Michael Papis.

• Warn only once when a gemspec license is invalid. Pull request #1414 by Samuel
  E. Giddins.
• Check for exact constants before using them, fixing Ruby bug #11940. Pull
  request #1438 by Nobuyoshi Nakada.
• Fix building C extensions on Ruby 1.9.x on Windows. Pull request #1453 by Marie
  Markwell.
• Handle symlinks containing ".." correctly. Pull request #1457 by Samuel E.
  Giddins.

Minor enhancements:

• Add --no-rc flag, which skips loading .gemrc. Pull request #1329 by Luis
  Sagastume.
• Allow basic auth to be excluded from allowed_push_host. By Josh Lane.
• Add gem list --exact, which finds gems by string match instead of regex. Pull
  request #1344 by Luis Sagastume.
• Suggest alternatives when gem license is unknown. Pull request #1443 by Samuel
  E. Giddins.
• Print a useful error if a binstub expects a newer version of a gem than is
  installed. Pull request #1407 by Samuel E. Giddins.
• Allow the (supported) s3:// scheme to be used with --source. Pull request

  1416 by Dave Adams.

• Add --[no-]post-install-message to install and update. Pull request #1162
  by Josef Šimánek.
• Add --host option to yank, providing symmetry with pull. Pull request

  1361 by Mike Virata-Stone.

• Update bundled Molinillo to 0.4.1. Pull request #1452 by Samuel E. Giddins.
• Allow calling build without '.gemspec'. Pull request #1454 by Stephen
  Blackstone.
• Add support for source option on gems in Gemfile. Pull request #1355 by
  Michael Papis.
• Function correctly when string literals are frozen on Ruby 2.3. Pull request

  1408 by Samuel E. Giddins.

RubyGems installed the following executables:
/System/Library/Frameworks/Ruby.framework/Versions/2.3/usr/bin/gem

Ruby Interactive (ri) documentation was installed. ri is kind of like man
pages for ruby libraries. You may access it like this:
ri Classname
ri Classname.class_method
ri Classname#instance_method
If you do not wish to install this documentation in the future, use the
--no-document flag, or set it as the default in your ~/.gemrc file. See
'gem help env' for details.

RubyGems system software updated

卸载cocoapods

$sudo gem uninstall cocoapods

重新安装cocoapods

$ sudo gem install -n /usr/local/bin cocoapods

Successfully installed xcodeproj-1.5.4
Fetching: escape-0.0.4.gem (100%)
Successfully installed escape-0.0.4
Fetching: fourflusher-2.0.1.gem (100%)
Successfully installed fourflusher-2.0.1
Fetching: gh_inspector-1.0.3.gem (100%)
Successfully installed gh_inspector-1.0.3
Fetching: ruby-macho-1.1.0.gem (100%)
Successfully installed ruby-macho-1.1.0
Fetching: cocoapods-1.4.0.gem (100%)
Successfully installed cocoapods-1.4.0
Parsing documentation for xcodeproj-1.5.4
Installing ri documentation for xcodeproj-1.5.4
Parsing documentation for escape-0.0.4
Installing ri documentation for escape-0.0.4
Parsing documentation for fourflusher-2.0.1
Installing ri documentation for fourflusher-2.0.1
Parsing documentation for gh_inspector-1.0.3
Installing ri documentation for gh_inspector-1.0.3
Parsing documentation for ruby-macho-1.1.0
Installing ri documentation for ruby-macho-1.1.0
Parsing documentation for cocoapods-1.4.0
Installing ri documentation for cocoapods-1.4.0
Done installing documentation for xcodeproj, escape, fourflusher, gh_inspector, ruby-macho, cocoapods after 8 seconds
6 gems installed
me:te JunJie$ pod setup
Setting up CocoaPods master repo
$ /usr/bin/git -C /Users/weijunjie/.cocoapods/repos/master fetch origin
--progress
remote: Counting objects: 1001712, done.
remote: Compressing objects: 100% (245/245), done.
Receiving objects: 100% (1001712/1001712), 159.27 MiB | 31.00 KiB/s, done.
remote: Total 1001712 (delta 35411), reused 35301 (delta 35301), pack-reused 966150
Resolving deltas: 100% (663514/663514), completed with 3845 local objects.
From https://github.com/CocoaPods/Specs
83e8a706fb5..15b1c89c5fc master -> origin/master

• [new branch] backz -> origin/backz
• [new branch] predates_sharding_branch -> origin/predates_sharding_branch
• [new branch] swift_version_support -> origin/swift_version_support
• [new tag] v0.32.1 -> v0.32.1
  $ /usr/bin/git -C /Users/weijunjie/.cocoapods/repos/master rev-parse
  --abbrev-ref HEAD
  master
  $ /usr/bin/git -C /Users/weijunjie/.cocoapods/repos/master reset --hard
  origin/master
  Checking out files: 100% (327026/327026), done.
  HEAD is now at 15b1c89c5fc [Add] WKWebViewController 1.0.0
  warning: inexact rename detection was skipped due to too many files.
  Setup completed

搞定

$ pod search sdwebimage

SDWebImage (4.2.3)
Asynchronous image downloader with cache support with an UIImageView
category.
pod 'SDWebImage', '~> 4.2.3'

• Homepage: https://github.com/rs/SDWebImage
• Source: https://github.com/rs/SDWebImage.git
• Versions: 4.2.3, 4.2.2, 4.2.1, 4.2.0, 4.1.2, 4.1.1, 4.1.0, 4.0.0,
  4.0.0-beta2, 4.0.0-beta, 3.8.2, 3.8.1, 3.8.0, 3.7.6, 3.7.5, 3.7.4, 3.7.3,
  3.7.2, 3.7.1, 3.7.0, 3.6, 3.5.4, 3.5.2, 3.5.1, 3.5, 3.4, 3.3, 3.2, 3.1, 3.0,
  2.7.4, 2.7, 2.6, 2.5, 2.4 [master repo]
• Subspecs:
  • SDWebImage/Core (4.2.3)
  • SDWebImage/MapKit (4.2.3)
  • SDWebImage/GIF (4.2.3)
  • SDWebImage/WebP (4.2.3)

总结:

电脑版本升级后,cocoapods无法使用,淘宝的镜像无法使用,需要设置镜像为gem source -a https://gems.ruby-china.org/,更新gem,卸载cocoapods,在安装cocoapods即可!