1 files changed, 125 insertions, 0 deletions
diff --git a/lib/bundler/vendor/molinillo/lib/molinillo/dependency_graph/log.rb b/lib/bundler/vendor/molinillo/lib/molinillo/dependency_graph/log.rb
new file mode 100644
index 0000000000..72a705e023
--- /dev/null
+++ b/lib/bundler/vendor/molinillo/lib/molinillo/dependency_graph/log.rb
@@ -0,0 +1,125 @@
+# frozen_string_literal: true
+require 'bundler/vendor/molinillo/lib/molinillo/dependency_graph/add_edge_no_circular'
+require 'bundler/vendor/molinillo/lib/molinillo/dependency_graph/add_vertex'
+require 'bundler/vendor/molinillo/lib/molinillo/dependency_graph/delete_edge'
+require 'bundler/vendor/molinillo/lib/molinillo/dependency_graph/detach_vertex_named'
+require 'bundler/vendor/molinillo/lib/molinillo/dependency_graph/set_payload'
+require 'bundler/vendor/molinillo/lib/molinillo/dependency_graph/tag'
+
+module Bundler::Molinillo
+  class DependencyGraph
+    # A log for dependency graph actions
+    class Log
+      # Initializes an empty log
+      def initialize
+        @current_action = @first_action = nil
+      end
+
+      # @!macro [new] action
+      #   {include:DependencyGraph#$0}
+      #   @param [Graph] graph the graph to perform the action on
+      #   @param (see DependencyGraph#$0)
+      #   @return (see DependencyGraph#$0)
+
+      # @macro action
+      def tag(graph, tag)
+        push_action(graph, Tag.new(tag))
+      end
+
+      # @macro action
+      def add_vertex(graph, name, payload, root)
+        push_action(graph, AddVertex.new(name, payload, root))
+      end
+
+      # @macro action
+      def detach_vertex_named(graph, name)
+        push_action(graph, DetachVertexNamed.new(name))
+      end
+
+      # @macro action
+      def add_edge_no_circular(graph, origin, destination, requirement)
+        push_action(graph, AddEdgeNoCircular.new(origin, destination, requirement))
+      end
+
+      # {include:DependencyGraph#delete_edge}
+      # @param [Graph] graph the graph to perform the action on
+      # @param [String] origin_name
+      # @param [String] destination_name
+      # @param [Object] requirement
+      # @return (see DependencyGraph#delete_edge)
+      def delete_edge(graph, origin_name, destination_name, requirement)
+        push_action(graph, DeleteEdge.new(origin_name, destination_name, requirement))
+      end
+
+      # @macro action
+      def set_payload(graph, name, payload)
+        push_action(graph, SetPayload.new(name, payload))
+      end
+
+      # Pops the most recent action from the log and undoes the action
+      # @param [DependencyGraph] graph
+      # @return [Action] the action that was popped off the log
+      def pop!(graph)
+        return unless action = @current_action
+        unless @current_action = action.previous
+          @first_action = nil
+        end
+        action.down(graph)
+        action
+      end
+
+      extend Enumerable
+
+      # @!visibility private
+      # Enumerates each action in the log
+      # @yield [Action]
+      def each
+        return enum_for unless block_given?
+        action = @first_action
+        loop do
+          break unless action
+          yield action
+          action = action.next
+        end
+        self
+      end
+
+      # @!visibility private
+      # Enumerates each action in the log in reverse order
+      # @yield [Action]
+      def reverse_each
+        return enum_for(:reverse_each) unless block_given?
+        action = @current_action
+        loop do
+          break unless action
+          yield action
+          action = action.previous
+        end
+        self
+      end
+
+      # @macro action
+      def rewind_to(graph, tag)
+        loop do
+          action = pop!(graph)
+          raise "No tag #{tag.inspect} found" unless action
+          break if action.class.action_name == :tag && action.tag == tag
+        end
+      end
+
+      private
+
+      # Adds the given action to the log, running the action
+      # @param [DependencyGraph] graph
+      # @param [Action] action
+      # @return The value returned by `action.up`
+      def push_action(graph, action)
+        action.previous = @current_action
+        @current_action.next = action if @current_action
+        @current_action = action
+        @first_action ||= action
+        action.up(graph)
+      end
+    end
+  end
+end