merge revision(s) 57412: [Backport #13308]

Update Rubygems 2.6.10

	 * 2ee5bf9fd3
	 * be510dd409

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_2_4@57952 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

lib/rubygems/resolver/molinillo/lib/molinillo/dependency_graph.rb

@@ -119,6 +119,7 @@ module Gem::Resolver::Molinillo
     #   {Vertex#successors}
     def ==(other)
       return false unless other
+      return true if equal?(other)
       vertices.each do |name, vertex|
         other_vertex = other.vertex_named(name)
         return false unless other_vertex
@@ -134,6 +135,7 @@ module Gem::Resolver::Molinillo
     def add_child_vertex(name, payload, parent_names, requirement)
       root = !parent_names.delete(nil) { true }
       vertex = add_vertex(name, payload, root)
+      vertex.explicit_requirements << requirement if root
       parent_names.each do |parent_name|
         parent_node = vertex_named(parent_name)
         add_edge(parent_node, vertex, requirement)
@@ -152,7 +154,7 @@ module Gem::Resolver::Molinillo
     # Detaches the {#vertex_named} `name` {Vertex} from the graph, recursively
     # removing any non-root vertices that were orphaned in the process
     # @param [String] name
-    # @return [void]
+    # @return [Array<Vertex>] the vertices which have been detached
     def detach_vertex_named(name)
       log.detach_vertex_named(self, name)
     end

lib/rubygems/resolver/molinillo/lib/molinillo/dependency_graph/detach_vertex_named.rb

@@ -14,16 +14,23 @@ module Gem::Resolver::Molinillo
 
       # (see Action#up)
       def up(graph)
-        return unless @vertex = graph.vertices.delete(name)
+        return [] unless @vertex = graph.vertices.delete(name)
+
+        removed_vertices = [@vertex]
         @vertex.outgoing_edges.each do |e|
           v = e.destination
           v.incoming_edges.delete(e)
-          graph.detach_vertex_named(v.name) unless v.root? || v.predecessors.any?
+          if !v.root? && v.incoming_edges.empty?
+            removed_vertices.concat graph.detach_vertex_named(v.name)
+          end
         end
+
         @vertex.incoming_edges.each do |e|
           v = e.origin
           v.outgoing_edges.delete(e)
         end
+
+        removed_vertices
       end
 
       # (see Action#down)

lib/rubygems/resolver/molinillo/lib/molinillo/dependency_graph/vertex.rb

@@ -81,6 +81,7 @@ module Gem::Resolver::Molinillo
       # @return [Boolean] whether the two vertices are equal, determined
       #   by a recursive traversal of each {Vertex#successors}
       def ==(other)
+        return true if equal?(other)
         shallow_eql?(other) &&
           successors.to_set == other.successors.to_set
       end
@@ -89,6 +90,7 @@ module Gem::Resolver::Molinillo
       # @return [Boolean] whether the two vertices are equal, determined
       #   solely by {#name} and {#payload} equality
       def shallow_eql?(other)
+        return true if equal?(other)
         other &&
           name == other.name &&
           payload == other.payload

lib/rubygems/resolver/molinillo/lib/molinillo/gem_metadata.rb

@@ -1,5 +1,5 @@
 # frozen_string_literal: true
 module Gem::Resolver::Molinillo
   # The version of Gem::Resolver::Molinillo.
-  VERSION = '0.5.3'.freeze
+  VERSION = '0.5.5'.freeze
 end

lib/rubygems/resolver/molinillo/lib/molinillo/resolution.rb

@@ -194,18 +194,20 @@ module Gem::Resolver::Molinillo
       def state_index_for_unwind
         current_requirement = requirement
         existing_requirement = requirement_for_existing_name(name)
-        until current_requirement.nil?
-          current_state = find_state_for(current_requirement)
-          return states.index(current_state) if state_any?(current_state)
-          current_requirement = parent_of(current_requirement)
+        index = -1
+        [current_requirement, existing_requirement].each do |r|
+          until r.nil?
+            current_state = find_state_for(r)
+            if state_any?(current_state)
+              current_index = states.index(current_state)
+              index = current_index if current_index > index
+              break
+            end
+            r = parent_of(r)
+          end
         end
 
-        until existing_requirement.nil?
-          existing_state = find_state_for(existing_requirement)
-          return states.index(existing_state) if state_any?(existing_state)
-          existing_requirement = parent_of(existing_requirement)
-        end
-        -1
+        index
       end
 
       # @return [Object] the requirement that led to `requirement` being added
@@ -364,19 +366,17 @@ module Gem::Resolver::Molinillo
           if matching_deps.empty? && !succ.root? && succ.predecessors.to_a == [vertex]
             debug(depth) { "Removing orphaned spec #{succ.name} after swapping #{name}" }
             succ.requirements.each { |r| @parent_of.delete(r) }
-            activated.detach_vertex_named(succ.name)
 
-            all_successor_names = succ.recursive_successors.map(&:name)
-
-            requirements.delete_if do |requirement|
-              requirement_name = name_for(requirement)
-              (requirement_name == succ.name) || all_successor_names.include?(requirement_name)
+            removed_names = activated.detach_vertex_named(succ.name).map(&:name)
+            requirements.delete_if do |r|
+              # the only removed vertices are those with no other requirements,
+              # so it's safe to delete only based upon name here
+              removed_names.include?(name_for(r))
             end
           elsif !matching_deps.include?(outgoing_edge.requirement)
             activated.delete_edge(outgoing_edge)
             requirements.delete(outgoing_edge.requirement)
           end
-          matching_deps.delete(outgoing_edge.requirement)
         end
       end