class Gem::DependencyList

Gem::DependencyList is used for installing and uninstalling gems in the correct order to avoid conflicts.

Attributes

development[RW]

Allows enabling/disabling use of development dependencies

specs[R]

Public Class Methods

from_specs() click to toggle source

Creates a DependencyList from the current specs.

# File lib/rubygems/dependency_list.rb, line 32
def self.from_specs
  list = new
  list.add(*Gem::Specification.to_a)
  list
end

new(development = false) click to toggle source

Creates a new DependencyList. If development is true, development dependencies will be included.

# File lib/rubygems/dependency_list.rb, line 42
def initialize development = false
  @specs = []

  @development = development
end

Public Instance Methods

add(*gemspecs) click to toggle source

Adds gemspecs to the dependency list.

# File lib/rubygems/dependency_list.rb, line 51
def add(*gemspecs)
  @specs.concat gemspecs
end

clear() click to toggle source

# File lib/rubygems/dependency_list.rb, line 55
def clear
  @specs.clear
end

dependency_order() click to toggle source

Return a list of the gem specifications in the dependency list, sorted in order so that no gemspec in the list depends on a gemspec earlier in the list.

This is useful when removing gems from a set of installed gems. By removing them in the returned order, you don't get into as many dependency issues.

If there are circular dependencies (yuck!), then gems will be returned in order until only the circular dependents and anything they reference are left. Then arbitrary gemspecs will be returned until the circular dependency is broken, after which gems will be returned in dependency order again.

# File lib/rubygems/dependency_list.rb, line 74
def dependency_order
  sorted = strongly_connected_components.flatten

  result = []
  seen = {}

  sorted.each do |spec|
    if index = seen[spec.name] then
      if result[index].version < spec.version then
        result[index] = spec
      end
    else
      seen[spec.name] = result.length
      result << spec
    end
  end

  result.reverse
end

each(&block) click to toggle source

Iterator over #dependency_order

# File lib/rubygems/dependency_list.rb, line 97
def each(&block)
  dependency_order.each(&block)
end

find_name(full_name) click to toggle source

# File lib/rubygems/dependency_list.rb, line 101
def find_name(full_name)
  @specs.find { |spec| spec.full_name == full_name }
end

ok?() click to toggle source

Are all the dependencies in the list satisfied?

# File lib/rubygems/dependency_list.rb, line 112
def ok?
  why_not_ok?(:quick).empty?
end

ok_to_remove?(full_name, check_dev=true) click to toggle source

Is is ok to remove a gemspec from the dependency list?

If removing the gemspec creates breaks a currently ok dependency, then it is NOT ok to remove the gemspec.

# File lib/rubygems/dependency_list.rb, line 141
def ok_to_remove?(full_name, check_dev=true)
  gem_to_remove = find_name full_name

  # If the state is inconsistent, at least don't crash
  return true unless gem_to_remove

  siblings = @specs.find_all { |s|
    s.name == gem_to_remove.name &&
      s.full_name != gem_to_remove.full_name
  }

  deps = []

  @specs.each do |spec|
    check = check_dev ? spec.dependencies : spec.runtime_dependencies

    check.each do |dep|
      deps << dep if gem_to_remove.satisfies_requirement?(dep)
    end
  end

  deps.all? { |dep|
    siblings.any? { |s|
      s.satisfies_requirement? dep
    }
  }
end

remove_by_name(full_name) click to toggle source

Removes the gemspec matching full_name from the dependency list

# File lib/rubygems/dependency_list.rb, line 184
def remove_by_name(full_name)
  @specs.delete_if { |spec| spec.full_name == full_name }
end

remove_specs_unsatisfied_by(dependencies) click to toggle source

Remove everything in the DependencyList that matches but doesn't satisfy items in dependencies (a hash of gem names to arrays of dependencies).

# File lib/rubygems/dependency_list.rb, line 174
def remove_specs_unsatisfied_by dependencies
  specs.reject! { |spec|
    dep = dependencies[spec.name]
    dep and not dep.requirement.satisfied_by? spec.version
  }
end

spec_predecessors() click to toggle source

Return a hash of predecessors. result[spec] is an Array of gemspecs that have a dependency satisfied by the named gemspec.

# File lib/rubygems/dependency_list.rb, line 192
def spec_predecessors
  result = Hash.new { |h,k| h[k] = [] }

  specs = @specs.sort.reverse

  specs.each do |spec|
    specs.each do |other|
      next if spec == other

      other.dependencies.each do |dep|
        if spec.satisfies_requirement? dep then
          result[spec] << other
        end
      end
    end
  end

  result
end

tsort_each_child(node) { |spec| ... } click to toggle source

# File lib/rubygems/dependency_list.rb, line 216
def tsort_each_child(node)
  specs = @specs.sort.reverse

  dependencies = node.runtime_dependencies
  dependencies.push(*node.development_dependencies) if @development

  dependencies.each do |dep|
    specs.each do |spec|
      if spec.satisfies_requirement? dep then
        yield spec
        break
      end
    end
  end
end

tsort_each_node(&block) click to toggle source

# File lib/rubygems/dependency_list.rb, line 212
def tsort_each_node(&block)
  @specs.each(&block)
end

why_not_ok?(quick = false) click to toggle source

# File lib/rubygems/dependency_list.rb, line 116
def why_not_ok? quick = false
  unsatisfied = Hash.new { |h,k| h[k] = [] }
  each do |spec|
    spec.runtime_dependencies.each do |dep|
      inst = Gem::Specification.any? { |installed_spec|
        dep.name == installed_spec.name and
          dep.requirement.satisfied_by? installed_spec.version
      }

      unless inst or @specs.find { |s| s.satisfies_requirement? dep } then
        unsatisfied[spec.name] << dep
        return unsatisfied if quick
      end
    end
  end

  unsatisfied
end