1 files changed, 159 insertions, 0 deletions
diff --git a/lib/rubygems/resolver/activation_request.rb b/lib/rubygems/resolver/activation_request.rb
new file mode 100644
index 0000000000..5c722001b1
--- /dev/null
+++ b/lib/rubygems/resolver/activation_request.rb
@@ -0,0 +1,159 @@
+# frozen_string_literal: true
+
+##
+# Specifies a Specification object that should be activated.  Also contains a
+# dependency that was used to introduce this activation.
+
+class Gem::Resolver::ActivationRequest
+  ##
+  # The parent request for this activation request.
+
+  attr_reader :request
+
+  ##
+  # The specification to be activated.
+
+  attr_reader :spec
+
+  ##
+  # Creates a new ActivationRequest that will activate +spec+.  The parent
+  # +request+ is used to provide diagnostics in case of conflicts.
+
+  def initialize(spec, request)
+    @spec = spec
+    @request = request
+  end
+
+  def ==(other) # :nodoc:
+    case other
+    when Gem::Specification
+      @spec == other
+    when Gem::Resolver::ActivationRequest
+      @spec == other.spec
+    else
+      false
+    end
+  end
+
+  def eql?(other)
+    self == other
+  end
+
+  def hash
+    @spec.hash
+  end
+
+  ##
+  # Is this activation request for a development dependency?
+
+  def development?
+    @request.development?
+  end
+
+  ##
+  # Downloads a gem at +path+ and returns the file path.
+
+  def download(path)
+    Gem.ensure_gem_subdirectories path
+
+    if @spec.respond_to? :sources
+      exception = nil
+      path = @spec.sources.find do |source|
+        source.download full_spec, path
+      rescue exception
+      end
+      return path      if path
+      raise  exception if exception
+
+    elsif @spec.respond_to? :source
+      source = @spec.source
+      source.download full_spec, path
+
+    else
+      source = Gem.sources.first
+      source.download full_spec, path
+    end
+  end
+
+  ##
+  # The full name of the specification to be activated.
+
+  def full_name
+    name_tuple.full_name
+  end
+
+  alias_method :to_s, :full_name
+
+  ##
+  # The Gem::Specification for this activation request.
+
+  def full_spec
+    Gem::Specification === @spec ? @spec : @spec.spec
+  end
+
+  def inspect # :nodoc:
+    format("#<%s for %p from %s>", self.class, @spec, @request)
+  end
+
+  ##
+  # True if the requested gem has already been installed.
+
+  def installed?
+    case @spec
+    when Gem::Resolver::VendorSpecification then
+      true
+    else
+      this_spec = full_spec
+
+      Gem::Specification.any? do |s|
+        s == this_spec && s.base_dir == this_spec.base_dir
+      end
+    end
+  end
+
+  ##
+  # The name of this activation request's specification
+
+  def name
+    @spec.name
+  end
+
+  ##
+  # Return the ActivationRequest that contained the dependency
+  # that we were activated for.
+
+  def parent
+    @request.requester
+  end
+
+  def pretty_print(q) # :nodoc:
+    q.group 2, "[Activation request", "]" do
+      q.breakable
+      q.pp @spec
+
+      q.breakable
+      q.text " for "
+      q.pp @request
+    end
+  end
+
+  ##
+  # The version of this activation request's specification
+
+  def version
+    @spec.version
+  end
+
+  ##
+  # The platform of this activation request's specification
+
+  def platform
+    @spec.platform
+  end
+
+  private
+
+  def name_tuple
+    @name_tuple ||= Gem::NameTuple.new(name, version, platform)
+  end
+end