1 files changed, 244 insertions, 0 deletions
diff --git a/lib/rubygems/source/git.rb b/lib/rubygems/source/git.rb
new file mode 100644
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+++ b/lib/rubygems/source/git.rb
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+# frozen_string_literal: true
+
+##
+# A git gem for use in a gem dependencies file.
+#
+# Example:
+#
+#   source =
+#     Gem::Source::Git.new 'rake', 'git@example:rake.git', 'rake-10.1.0', false
+#
+#   source.specs
+
+class Gem::Source::Git < Gem::Source
+  ##
+  # The name of the gem created by this git gem.
+
+  attr_reader :name
+
+  ##
+  # The commit reference used for checking out this git gem.
+
+  attr_reader :reference
+
+  ##
+  # When false the cache for this repository will not be updated.
+
+  attr_accessor :remote
+
+  ##
+  # The git repository this gem is sourced from.
+
+  attr_reader :repository
+
+  ##
+  # The directory for cache and git gem installation
+
+  attr_accessor :root_dir
+
+  ##
+  # Does this repository need submodules checked out too?
+
+  attr_reader :need_submodules
+
+  ##
+  # Creates a new git gem source for a gems from loaded from +repository+ at
+  # the given +reference+.  The +name+ is only used to track the repository
+  # back to a gem dependencies file, it has no real significance as a git
+  # repository may contain multiple gems.  If +submodules+ is true, submodules
+  # will be checked out when the gem is installed.
+
+  def initialize(name, repository, reference, submodules = false)
+    require_relative "../uri"
+    @uri = Gem::Uri.parse(repository)
+    @name            = name
+    @repository      = repository
+    @reference       = reference || "HEAD"
+    @need_submodules = submodules
+
+    @remote   = true
+    @root_dir = Gem.dir
+  end
+
+  def <=>(other)
+    case other
+    when Gem::Source::Git then
+      0
+    when Gem::Source::Vendor,
+         Gem::Source::Lock then
+      -1
+    when Gem::Source then
+      1
+    end
+  end
+
+  def ==(other) # :nodoc:
+    super &&
+      @name            == other.name &&
+      @repository      == other.repository &&
+      @reference       == other.reference &&
+      @need_submodules == other.need_submodules
+  end
+
+  def git_command
+    ENV.fetch("git", "git")
+  end
+
+  ##
+  # Checks out the files for the repository into the install_dir.
+
+  def checkout # :nodoc:
+    cache
+
+    return false unless File.exist? repo_cache_dir
+
+    unless File.exist? install_dir
+      system git_command, "clone", "--quiet", "--no-checkout",
+             repo_cache_dir, install_dir
+    end
+
+    Dir.chdir install_dir do
+      system git_command, "fetch", "--quiet", "--force", "--tags", install_dir
+
+      success = system git_command, "reset", "--quiet", "--hard", rev_parse
+
+      if @need_submodules
+        require "open3"
+        _, status = Open3.capture2e(git_command, "submodule", "update", "--quiet", "--init", "--recursive")
+
+        success &&= status.success?
+      end
+
+      success
+    end
+  end
+
+  ##
+  # Creates a local cache repository for the git gem.
+
+  def cache # :nodoc:
+    return unless @remote
+
+    if File.exist? repo_cache_dir
+      Dir.chdir repo_cache_dir do
+        system git_command, "fetch", "--quiet", "--force", "--tags",
+               @repository, "refs/heads/*:refs/heads/*"
+      end
+    else
+      system git_command, "clone", "--quiet", "--bare", "--no-hardlinks",
+             @repository, repo_cache_dir
+    end
+  end
+
+  ##
+  # Directory where git gems get unpacked and so-forth.
+
+  def base_dir # :nodoc:
+    File.join @root_dir, "bundler"
+  end
+
+  ##
+  # A short reference for use in git gem directories
+
+  def dir_shortref # :nodoc:
+    rev_parse[0..11]
+  end
+
+  ##
+  # Nothing to download for git gems
+
+  def download(full_spec, path) # :nodoc:
+  end
+
+  ##
+  # The directory where the git gem will be installed.
+
+  def install_dir # :nodoc:
+    return unless File.exist? repo_cache_dir
+
+    File.join base_dir, "gems", "#{@name}-#{dir_shortref}"
+  end
+
+  def pretty_print(q) # :nodoc:
+    q.object_group(self) do
+      q.group 2, "[Git: ", "]" do
+        q.breakable
+        q.text @repository
+
+        q.breakable
+        q.text @reference
+      end
+    end
+  end
+
+  ##
+  # The directory where the git gem's repository will be cached.
+
+  def repo_cache_dir # :nodoc:
+    File.join @root_dir, "cache", "bundler", "git", "#{@name}-#{uri_hash}"
+  end
+
+  ##
+  # Converts the git reference for the repository into a commit hash.
+
+  def rev_parse # :nodoc:
+    hash = nil
+
+    Dir.chdir repo_cache_dir do
+      hash = Gem::Util.popen(git_command, "rev-parse", @reference).strip
+    end
+
+    raise Gem::Exception,
+          "unable to find reference #{@reference} in #{@repository}" unless
+            $?.success?
+
+    hash
+  end
+
+  ##
+  # Loads all gemspecs in the repository
+
+  def specs
+    checkout
+
+    return [] unless install_dir
+
+    Dir.chdir install_dir do
+      Dir["{,*,*/*}.gemspec"].filter_map do |spec_file|
+        directory = File.dirname spec_file
+        file      = File.basename spec_file
+
+        Dir.chdir directory do
+          spec = Gem::Specification.load file
+          if spec
+            spec.base_dir = base_dir
+
+            spec.extension_dir =
+              File.join base_dir, "extensions", Gem::Platform.local.to_s,
+                Gem.extension_api_version, "#{name}-#{dir_shortref}"
+
+            spec.full_gem_path = File.dirname spec.loaded_from if spec
+          end
+          spec
+        end
+      end
+    end
+  end
+
+  ##
+  # A hash for the git gem based on the git repository Gem::URI.
+
+  def uri_hash # :nodoc:
+    require_relative "../openssl"
+
+    normalized =
+      if @repository.match?(%r{^\w+://(\w+@)?})
+        uri = Gem::URI(@repository).normalize.to_s.sub %r{/$},""
+        uri.sub(/\A(\w+)/) { $1.downcase }
+      else
+        @repository
+      end
+
+    OpenSSL::Digest::SHA1.hexdigest normalized
+  end
+end