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Class: Gem::Resolver::Molinillo::Resolver::Resolution

Relationships & Source Files
Namespace Children
Classes:
Conflict
Super Chains via Extension / Inclusion / Inheritance
Instance Chain:
self, ::Gem::Resolver::Molinillo::Delegates::SpecificationProvider, ::Gem::Resolver::Molinillo::Delegates::ResolutionState
Inherits: Object
Defined in: lib/rubygems/resolver/molinillo/lib/molinillo/resolution.rb

Overview

A specific resolution from a given ::Gem::Resolver::Molinillo::Resolver

Class Method Summary

Instance Attribute Summary

Instance Method Summary

::Gem::Resolver::Molinillo::Delegates::SpecificationProvider - Included

#allow_missing?

Returns whether this dependency, which has no possible matching specifications, can safely be ignored.
#dependencies_for

Returns the dependencies of specification.
#name_for

Returns the name for the given dependency.
#name_for_explicit_dependency_source, #name_for_locking_dependency_source,
#requirement_satisfied_by?

Determines whether the given requirement is satisfied by the given spec, in the context of the current activated dependency graph.
#search_for

Search for the specifications that match the given dependency.
#sort_dependencies

Sort dependencies so that the ones that are easiest to resolve are first.
#with_no_such_dependency_error_handling

Ensures any raised ::Gem::Resolver::Molinillo::NoSuchDependencyError has its NoSuchDependencyError#required_by set.

::Gem::Resolver::Molinillo::Delegates::ResolutionState - Included

#activated

A state that a Resolution can be in.
#conflicts

A state that a Resolution can be in.
#depth

A state that a Resolution can be in.
#name

A state that a Resolution can be in.
#possibilities

A state that a Resolution can be in.
#requirement

A state that a Resolution can be in.
#requirements

A state that a Resolution can be in.

Constructor Details

.new(specification_provider, resolver_ui, requested, base) ⇒ Resolution

Initializes a new resolution.

Parameters:

[ GitHub ] 

  


# File 'lib/rubygems/resolver/molinillo/lib/molinillo/resolution.rb', line 48



def initialize(specification_provider, resolver_ui, requested, base)
  @specification_provider = specification_provider
  @resolver_ui = resolver_ui
  @original_requested = requested
  @base = base
  @states = []
  @iteration_counter = 0
  @parents_of = Hash.new { |h, k| h[k] = [] }
end


  







Instance Attribute Details



  

    #base  ⇒ DependencyGraph  (readonly)
  



  

    
  





  
Returns:


    
  
  • 
    (DependencyGraph)
—    
    

    the base dependency graph to which dependencies should be 'locked'
    

    
  
    • 





  [ GitHub ]


  

  


# File 'lib/rubygems/resolver/molinillo/lib/molinillo/resolution.rb', line 37



attr_reader :base


  








  

    #iteration_rate  ⇒ Integer  (rw, private)
  



  

    
  





  
Returns:





  [ GitHub ]


  

  


# File 'lib/rubygems/resolver/molinillo/lib/molinillo/resolution.rb', line 88



attr_accessor :iteration_rate


  








  

    #new_spec_satisfied?  ⇒ Boolean  (readonly, private)
  



  

    

possibility.


  





  
Returns:


    
  
  • 
    (Boolean)
—    
    

    whether the current spec is satisfied as a new
    

    
  
    • 





  [ GitHub ]


  

  


# File 'lib/rubygems/resolver/molinillo/lib/molinillo/resolution.rb', line 411



def new_spec_satisfied?
  unless requirement_satisfied_by?(requirement, activated, possibility)
    debug(depth) { 'Unsatisfied by requested spec' }
    return false
  end

  locked_requirement = locked_requirement_named(name)

  locked_spec_satisfied = !locked_requirement ||
    requirement_satisfied_by?(locked_requirement, activated, possibility)
  debug(depth) { 'Unsatisfied by locked spec' } unless locked_spec_satisfied

  locked_spec_satisfied
end


  








  

    #original_requested  ⇒ Array  (readonly)
  



  

    
  





  
Returns:


    
  
  • 
    (Array)
—    
    

    the dependencies that were explicitly required
    

    
  
    • 





  [ GitHub ]


  

  


# File 'lib/rubygems/resolver/molinillo/lib/molinillo/resolution.rb', line 40



attr_reader :original_requested


  








  

    #resolver_ui  ⇒ UI  (readonly)
  



  

    
  





  
Returns:





  [ GitHub ]


  

  


# File 'lib/rubygems/resolver/molinillo/lib/molinillo/resolution.rb', line 33



attr_reader :resolver_ui


  








  

    #specification_provider  ⇒ SpecificationProvider  (readonly)
  



  

    
  





  
Returns:


    
  
  • 
    (SpecificationProvider)
—    
    

    the provider that knows about dependencies, requirements, specifications, versions, etc.
    

    
  
    • 





  [ GitHub ]


  

  


# File 'lib/rubygems/resolver/molinillo/lib/molinillo/resolution.rb', line 29



attr_reader :specification_provider


  








  

    #started_at  ⇒ Time  (rw, private)
  



  

    
  





  
Returns:


    
  
  • 
    (Time)
—    
    

    the time at which resolution began
    

    
  
    • 





  [ GitHub ]


  

  


# File 'lib/rubygems/resolver/molinillo/lib/molinillo/resolution.rb', line 92



attr_accessor :started_at


  








  

    #states  ⇒ Array<ResolutionState>  (rw, private)
  



  

    
  





  
Returns:





  [ GitHub ]


  

  


# File 'lib/rubygems/resolver/molinillo/lib/molinillo/resolution.rb', line 96



attr_accessor :states


  







Instance Method Details



  

    #activate_spec  ⇒ void  (private)
  



  

    
This method returns an undefined value.


Add the current #possibility to the dependency graph of the current #state


  





  


  [ GitHub ]


  

  


# File 'lib/rubygems/resolver/molinillo/lib/molinillo/resolution.rb', line 437



def activate_spec
  conflicts.delete(name)
  debug(depth) { "Activated #{name} at #{possibility}" }
  activated.set_payload(name, possibility)
  require_nested_dependencies_for(possibility)
end


  








  

    #attempt_to_activate  ⇒ void  (private)
  



  

    
This method returns an undefined value.


Attempts to activate the current #possibility


  





  


  [ GitHub ]


  

  


# File 'lib/rubygems/resolver/molinillo/lib/molinillo/resolution.rb', line 312



def attempt_to_activate
  debug(depth) { 'Attempting to activate ' + possibility.to_s }
  existing_node = activated.vertex_named(name)
  if existing_node.payload
    debug(depth) { "Found existing spec (#{existing_node.payload})" }
    attempt_to_activate_existing_spec(existing_node)
  else
    attempt_to_activate_new_spec
  end
end


  








  

    #attempt_to_activate_existing_spec(existing_node)  ⇒ void  (private)
  



  

    
This method returns an undefined value.


Attempts to activate the current #possibility (given that it has already been activated)


  





  


  [ GitHub ]


  

  


# File 'lib/rubygems/resolver/molinillo/lib/molinillo/resolution.rb', line 326



def attempt_to_activate_existing_spec(existing_node)
  existing_spec = existing_node.payload
  if requirement_satisfied_by?(requirement, activated, existing_spec)
    new_requirements = requirements.dup
    push_state_for_requirements(new_requirements, false)
  else
    return if attempt_to_swap_possibility
    create_conflict
    debug(depth) { "Unsatisfied by existing spec (#{existing_node.payload})" }
    unwind_for_conflict
  end
end


  








  

    #attempt_to_activate_new_spec  ⇒ void  (private)
  



  

    
This method returns an undefined value.


Attempts to activate the current #possibility (given that it hasn't already been activated)


  





  


  [ GitHub ]


  

  


# File 'lib/rubygems/resolver/molinillo/lib/molinillo/resolution.rb', line 400



def attempt_to_activate_new_spec
  if new_spec_satisfied?
    activate_spec
  else
    create_conflict
    unwind_for_conflict
  end
end


  








  

    #attempt_to_swap_possibility  ⇒ Boolean  (private)
  



  

    

Attempts to swp the current #possibility with the already-activated spec with the given name


  





  
Returns:


    
  
  • 
    (Boolean)
—    
    

    Whether the possibility was swapped into #activated
    

    
  
    • 





  [ GitHub ]


  

  


# File 'lib/rubygems/resolver/molinillo/lib/molinillo/resolution.rb', line 342



def attempt_to_swap_possibility
  activated.tag(:swap)
  vertex = activated.vertex_named(name)
  activated.set_payload(name, possibility)
  if !vertex.requirements.
     all? { |r| requirement_satisfied_by?(r, activated, possibility) } ||
      !new_spec_satisfied?
    activated.rewind_to(:swap)
    return
  end
  fixup_swapped_children(vertex)
  activate_spec
end


  








  

    #create_conflict  ⇒ Conflict  (private)
  



  

    
  





  
Returns:





  [ GitHub ]


  

  


# File 'lib/rubygems/resolver/molinillo/lib/molinillo/resolution.rb', line 244



def create_conflict
  vertex = activated.vertex_named(name)
  locked_requirement = locked_requirement_named(name)

  requirements = {}
  unless vertex.explicit_requirements.empty?
    requirements[name_for_explicit_dependency_source] = vertex.explicit_requirements
  end
  requirements[name_for_locking_dependency_source] = [locked_requirement] if locked_requirement
  vertex.incoming_edges.each { |edge| (requirements[edge.origin.payload] ||= []).unshift(edge.requirement) }

  activated_by_name = {}
  activated.each { |v| activated_by_name[v.name] = v.payload if v.payload }
  conflicts[name] = Conflict.new(
    requirement,
    requirements,
    vertex.payload,
    possibility,
    locked_requirement,
    requirement_trees,
    activated_by_name
  )
end


  








  

    #debug(depth = 0, &block)  ⇒ void  (private)
  



  

    
This method returns an undefined value.


Calls the #resolver_ui's UI#debug method


  





  
Parameters:


    
  
  • 
    depth
    (Integer)
    (defaults to: 0)
—    
    

    the depth of the #states stack
    

    
  
    • 
  
  • 
    block
    (Proc)
—    
    

    a block that yields a #to_s
    

    
  
    • 





  [ GitHub ]


  

  


# File 'lib/rubygems/resolver/molinillo/lib/molinillo/resolution.rb', line 306



def debug(depth = 0, &block)
  resolver_ui.debug(depth, &block)
end


  








  

    #end_resolution  ⇒ void  (private)
  



  

    
This method returns an undefined value.


Ends the resolution process


  





  


  [ GitHub ]


  

  


# File 'lib/rubygems/resolver/molinillo/lib/molinillo/resolution.rb', line 114



def end_resolution
  resolver_ui.after_resolution
  debug do
    "Finished resolution (#{@iteration_counter} steps) " \
    "(Took #{(ended_at = Time.now) - @started_at} seconds) (#{ended_at})"
  end
  debug { 'Unactivated: ' + Hash[activated.vertices.reject { |_n, v| v.payload }].keys.join(', ') } if state
  debug { 'Activated: ' + Hash[activated.vertices.select { |_n, v| v.payload }].keys.join(', ') } if state
end


  








  

    #find_state_for(requirement)  ⇒ ResolutionState  (private)
  



  

    
  





  
Returns:


    
  
  • 
    (ResolutionState)
—    
    

    the state whose requirement is the given requirement.
    

    
  
    • 





  [ GitHub ]


  

  


# File 'lib/rubygems/resolver/molinillo/lib/molinillo/resolution.rb', line 231



def find_state_for(requirement)
  return nil unless requirement
  states.reverse_each.find { |i| requirement == i.requirement && i.is_a?(DependencyState) }
end


  








  

    #fixup_swapped_children(vertex)  ⇒ void  (private)
  



  

    
This method returns an undefined value.


Ensures there are no orphaned successors to the given vertex.


  





  
Parameters:





  [ GitHub ]


  

  


# File 'lib/rubygems/resolver/molinillo/lib/molinillo/resolution.rb', line 359



def fixup_swapped_children(vertex) # rubocop:disable Metrics/CyclomaticComplexity
  payload = vertex.payload
  deps = dependencies_for(payload).group_by(&method(:name_for))
  vertex.outgoing_edges.each do |outgoing_edge|
    requirement = outgoing_edge.requirement
    parent_index = @parents_of[requirement].last
    succ = outgoing_edge.destination
    matching_deps = Array(deps[succ.name])
    dep_matched = matching_deps.include?(requirement)

    # only push the current index when it was originally required by the
    # same named spec
    if parent_index && states[parent_index].name == name
      @parents_of[requirement].push(states.size - 1)
    end

    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| @parents_of.delete(r) }

      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 !dep_matched
      debug(depth) { "Removing orphaned dependency #{requirement} after swapping #{name}" }
      # also reset if we're removing the edge, but only if its parent has
      # already been fixed up
      @parents_of[requirement].push(states.size - 1) if @parents_of[requirement].empty?

      activated.delete_edge(outgoing_edge)
      requirements.delete(requirement)
    end
  end
end


  








  

    #handle_missing_or_push_dependency_state(state)  ⇒ void  (private)
  



  

    
This method returns an undefined value.


Pushes a new ::Gem::Resolver::Molinillo::DependencyState. If the #specification_provider says to SpecificationProvider#allow_missing? that particular requirement, and there are no possibilities for that requirement, then #state is not pushed, and the node in #activated is removed, and we continue resolving the remaining requirements.


  





  
Parameters:





  [ GitHub ]


  

  


# File 'lib/rubygems/resolver/molinillo/lib/molinillo/resolution.rb', line 484



def handle_missing_or_push_dependency_state(state)
  if state.requirement && state.possibilities.empty? && allow_missing?(state.requirement)
    state.activated.detach_vertex_named(state.name)
    push_state_for_requirements(state.requirements.dup, false, state.activated)
  else
    states.push(state).tap { activated.tag(state) }
  end
end


  








  

    #indicate_progress  ⇒ void  (private)
  



  

    
This method returns an undefined value.


Indicates progress roughly once every second


  





  


  [ GitHub ]


  

  


# File 'lib/rubygems/resolver/molinillo/lib/molinillo/resolution.rb', line 288



def indicate_progress
  @iteration_counter += 1
  @progress_rate ||= resolver_ui.progress_rate
  if iteration_rate.nil?
    if Time.now - started_at >= @progress_rate
      self.iteration_rate = @iteration_counter
    end
  end

  if iteration_rate && (@iteration_counter % iteration_rate) == 0
    resolver_ui.indicate_progress
  end
end


  








  

    #initial_state  ⇒ DependencyState  (private)
  



  

    

Creates the initial state for the resolution, based upon the #requested dependencies


  





  
Returns:





  [ GitHub ]


  

  


# File 'lib/rubygems/resolver/molinillo/lib/molinillo/resolution.rb', line 159



def initial_state
  graph = DependencyGraph.new.tap do |dg|
    original_requested.each { |r| dg.add_vertex(name_for(r), nil, true).tap { |v| v.explicit_requirements << r } }
    dg.tag(:initial_state)
  end

  requirements = sort_dependencies(original_requested, graph, {})
  initial_requirement = requirements.shift
  DependencyState.new(
    initial_requirement && name_for(initial_requirement),
    requirements,
    graph,
    initial_requirement,
    initial_requirement && search_for(initial_requirement),
    0,
    {}
  )
end


  








  

    #locked_requirement_named(requirement_name)  ⇒ Object  (private)
  



  

    
  





  
Parameters:


    
  
  • 
    requirement_name
    (String)
—    
    

    the spec name to search for
    

    
  
    • 



Returns:


    
  
  • 
    (Object)
—    
    

    the locked spec named requirement_name, if one is found on #base
    

    
  
    • 





  [ GitHub ]


  

  


# File 'lib/rubygems/resolver/molinillo/lib/molinillo/resolution.rb', line 429



def locked_requirement_named(requirement_name)
  vertex = base.vertex_named(requirement_name)
  vertex && vertex.payload
end


  








  

    #parent_of(requirement)  ⇒ Object  (private)
  



  

    
  





  
Returns:


    
  
  • 
    (Object)
—    
    

    the requirement that led to requirement being added to the list of requirements.
    

    
  
    • 





  [ GitHub ]


  

  


# File 'lib/rubygems/resolver/molinillo/lib/molinillo/resolution.rb', line 215



def parent_of(requirement)
  return unless requirement
  return unless index = @parents_of[requirement].last
  return unless parent_state = @states[index]
  parent_state.requirement
end


  








  

    #possibility  ⇒ Object  (private)
  



  

    
  





  
Returns:


    
  
  • 
    (Object)
—    
    

    the current possibility that the resolution is trying to activate
    

    
  
    • 





  [ GitHub ]


  

  


# File 'lib/rubygems/resolver/molinillo/lib/molinillo/resolution.rb', line 146



def possibility
  possibilities.last
end


  








  

    #process_topmost_state  ⇒ void  (private)
  



  

    
This method returns an undefined value.


Processes the topmost available RequirementState on the stack


  





  


  [ GitHub ]


  

  


# File 'lib/rubygems/resolver/molinillo/lib/molinillo/resolution.rb', line 135



def process_topmost_state
  if possibility
    attempt_to_activate
  else
    create_conflict if state.is_a? PossibilityState
    unwind_for_conflict until possibility && state.is_a?(DependencyState)
  end
end


  








  

    #push_state_for_requirements(new_requirements, requires_sort = true, new_activated = activated)  ⇒ void  (private)
  



  

    
This method returns an undefined value.


Pushes a new ::Gem::Resolver::Molinillo::DependencyState that encapsulates both existing and new requirements


  





  
Parameters:


    
  
  • 
    new_requirements
    (Array)
  
    • 





  [ GitHub ]


  

  


# File 'lib/rubygems/resolver/molinillo/lib/molinillo/resolution.rb', line 465



def push_state_for_requirements(new_requirements, requires_sort = true, new_activated = activated)
  new_requirements = sort_dependencies(new_requirements.uniq, new_activated, conflicts) if requires_sort
  new_requirement = new_requirements.shift
  new_name = new_requirement ? name_for(new_requirement) : ''.freeze
  possibilities = new_requirement ? search_for(new_requirement) : []
  handle_missing_or_push_dependency_state DependencyState.new(
    new_name, new_requirements, new_activated,
    new_requirement, possibilities, depth, conflicts.dup
  )
end


  








  

    #require_nested_dependencies_for(activated_spec)  ⇒ void  (private)
  



  

    
This method returns an undefined value.


Requires the dependencies that the recently activated spec has


  





  
Parameters:


    
  
  • 
    activated_spec
    (Object)
—    
    

    the specification that has just been activated
    

    
  
    • 





  [ GitHub ]


  

  


# File 'lib/rubygems/resolver/molinillo/lib/molinillo/resolution.rb', line 448



def require_nested_dependencies_for(activated_spec)
  nested_dependencies = dependencies_for(activated_spec)
  debug(depth) { "Requiring nested dependencies (#{nested_dependencies.join(', ')})" }
  nested_dependencies.each do |d|
    activated.add_child_vertex(name_for(d), nil, [name_for(activated_spec)], d)
    parent_index = states.size - 1
    parents = @parents_of[d]
    parents << parent_index if parents.empty?
  end

  push_state_for_requirements(requirements + nested_dependencies, !nested_dependencies.empty?)
end


  








  

    #requirement_for_existing_name(name)  ⇒ Object  (private)
  



  

    
  





  
Returns:


    
  
  • 
    (Object)
—    
    

    the requirement that led to a version of a possibility with the given name being activated.
    

    
  
    • 





  [ GitHub ]


  

  


# File 'lib/rubygems/resolver/molinillo/lib/molinillo/resolution.rb', line 224



def requirement_for_existing_name(name)
  return nil unless activated.vertex_named(name).payload
  states.find { |s| s.name == name }.requirement
end


  








  

    #requirement_tree_for(requirement)  ⇒ Array<Object>  (private)
  



  

    
  





  
Returns:


    
  
  • 
    (Array<Object>)
—    
    

    the list of requirements that led to requirement being required.
    

    
  
    • 





  [ GitHub ]


  

  


# File 'lib/rubygems/resolver/molinillo/lib/molinillo/resolution.rb', line 277



def requirement_tree_for(requirement)
  tree = []
  while requirement
    tree.unshift(requirement)
    requirement = parent_of(requirement)
  end
  tree
end


  








  

    #requirement_trees  ⇒ Array<Array<Object>>  (private)
  



  

    
  





  
Returns:


    
  
  • 
    (Array<Array<Object>>)
—    
    

    The different requirement trees that led to every requirement for the current spec.
    

    
  
    • 





  [ GitHub ]


  

  


# File 'lib/rubygems/resolver/molinillo/lib/molinillo/resolution.rb', line 270



def requirement_trees
  vertex = activated.vertex_named(name)
  vertex.requirements.map { |r| requirement_tree_for(r) }
end


  








  

    #resolve  ⇒ DependencyGraph 
  



  

    

Resolves the #original_requested dependencies into a full dependency graph


  





  
Returns:


    
  
  • 
    (DependencyGraph)
—    
    

    the dependency graph of successfully resolved dependencies
    

    
  
    • 



Raises:





  [ GitHub ]


  

  


# File 'lib/rubygems/resolver/molinillo/lib/molinillo/resolution.rb', line 63



def resolve
  start_resolution

  while state
    break unless state.requirements.any? || state.requirement
    indicate_progress
    if state.respond_to?(:pop_possibility_state) # DependencyState
      debug(depth) { "Creating possibility state for #{requirement} (#{possibilities.count} remaining)" }
      state.pop_possibility_state.tap do |s|
        if s
          states.push(s)
          activated.tag(s)
        end
      end
    end
    process_topmost_state
  end

  activated.freeze
ensure
  end_resolution
end


  








  

    #start_resolution  ⇒ void  (private)
  



  

    
This method returns an undefined value.


Sets up the resolution process


  





  


  [ GitHub ]


  

  


# File 'lib/rubygems/resolver/molinillo/lib/molinillo/resolution.rb', line 103



def start_resolution
  @started_at = Time.now

  handle_missing_or_push_dependency_state(initial_state)

  debug { "Starting resolution (#{@started_at})\nUser-requested dependencies: #{original_requested}" }
  resolver_ui.before_resolution
end


  








  

    #state  ⇒ RequirementState  (private)
  



  

    
  





  
Returns:


    
  
  • 
    (RequirementState)
—    
    

    the current state the resolution is operating upon
    

    
  
    • 





  [ GitHub ]


  

  


# File 'lib/rubygems/resolver/molinillo/lib/molinillo/resolution.rb', line 152



def state
  states.last
end


  








  

    #state_any?(state)  ⇒ Boolean  (private)
  



  

    
  





  
Returns:


    
  
  • 
    (Boolean)
—    
    

    whether or not the given state has any possibilities left.
    

    
  
    • 





  [ GitHub ]


  

  


# File 'lib/rubygems/resolver/molinillo/lib/molinillo/resolution.rb', line 238



def state_any?(state)
  state && state.possibilities.any?
end


  








  

    #state_index_for_unwind  ⇒ Integer  (private)
  



  

    
  





  
Returns:


    
  
  • 
    (Integer)
—    
    

    The index to which the resolution should unwind in the case of conflict.
    

    
  
    • 





  [ GitHub ]


  

  


# File 'lib/rubygems/resolver/molinillo/lib/molinillo/resolution.rb', line 194



def state_index_for_unwind
  current_requirement = requirement
  existing_requirement = requirement_for_existing_name(name)
  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

  index
end


  








  

    #unwind_for_conflict  ⇒ void  (private)
  



  

    
This method returns an undefined value.


Unwinds the states stack because a conflict has been encountered


  





  


  [ GitHub ]


  

  


# File 'lib/rubygems/resolver/molinillo/lib/molinillo/resolution.rb', line 180



def unwind_for_conflict
  debug(depth) { "Unwinding for conflict: #{requirement} to #{state_index_for_unwind / 2}" }
  conflicts.tap do |c|
    sliced_states = states.slice!((state_index_for_unwind + 1)..-1)
    raise VersionConflict.new(c) unless state
    activated.rewind_to(sliced_states.first || :initial_state) if sliced_states
    state.conflicts = c
    index = states.size - 1
    @parents_of.each { |_, a| a.reject! { |i| i >= index } }
  end
end