Class: Gem::DependencyList

Inherits:
Object show all
Includes:
Enumerable, TSort
Defined in:
lib/rubygems/dependency_list.rb

Overview

Gem::DependencyList is used for installing and uninstalling gems in the correct order to avoid conflicts. – TODO: It appears that all but topo-sort functionality is being duplicated (or is planned to be duplicated) elsewhere in rubygems. Is the majority of this class necessary anymore? Especially #ok?, #why_not_ok?

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(development = false) ⇒ DependencyList

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



43
44
45
46
47
# File 'lib/rubygems/dependency_list.rb', line 43

def initialize(development = false)
  @specs = []

  @development = development
end

Instance Attribute Details

#developmentObject

Allows enabling/disabling use of development dependencies



28
29
30
# File 'lib/rubygems/dependency_list.rb', line 28

def development
  @development
end

#specsObject (readonly)

Returns the value of attribute specs.



20
21
22
# File 'lib/rubygems/dependency_list.rb', line 20

def specs
  @specs
end

Class Method Details

.from_specsObject

Creates a DependencyList from the current specs.



33
34
35
36
37
# File 'lib/rubygems/dependency_list.rb', line 33

def self.from_specs
  list = new
  list.add(*Gem::Specification.to_a)
  list
end

Instance Method Details

#add(*gemspecs) ⇒ Object

Adds gemspecs to the dependency list.



52
53
54
# File 'lib/rubygems/dependency_list.rb', line 52

def add(*gemspecs)
  @specs.concat gemspecs
end

#clearObject



56
57
58
# File 'lib/rubygems/dependency_list.rb', line 56

def clear
  @specs.clear
end

#dependency_orderObject

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.



75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
# File 'lib/rubygems/dependency_list.rb', line 75

def dependency_order
  sorted = strongly_connected_components.flatten

  result = []
  seen = {}

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

  result.reverse
end

#each(&block) ⇒ Object

Iterator over dependency_order



98
99
100
# File 'lib/rubygems/dependency_list.rb', line 98

def each(&block)
  dependency_order.each(&block)
end

#find_name(full_name) ⇒ Object



102
103
104
# File 'lib/rubygems/dependency_list.rb', line 102

def find_name(full_name)
  @specs.find {|spec| spec.full_name == full_name }
end

#inspectObject

:nodoc:



106
107
108
# File 'lib/rubygems/dependency_list.rb', line 106

def inspect # :nodoc:
  "%s %p>" % [super[0..-2], map {|s| s.full_name }]
end

#ok?Boolean

Are all the dependencies in the list satisfied?

Returns:

  • (Boolean)


113
114
115
# File 'lib/rubygems/dependency_list.rb', line 113

def ok?
  why_not_ok?(:quick).empty?
end

#ok_to_remove?(full_name, check_dev = true) ⇒ Boolean

It 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.

Returns:

  • (Boolean)


142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
# File 'lib/rubygems/dependency_list.rb', line 142

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 do |s|
    s.name == gem_to_remove.name &&
      s.full_name != gem_to_remove.full_name
  end

  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? do |dep|
    siblings.any? do |s|
      s.satisfies_requirement? dep
    end
  end
end

#remove_by_name(full_name) ⇒ Object

Removes the gemspec matching full_name from the dependency list



185
186
187
# File 'lib/rubygems/dependency_list.rb', line 185

def remove_by_name(full_name)
  @specs.delete_if {|spec| spec.full_name == full_name }
end

#remove_specs_unsatisfied_by(dependencies) ⇒ Object

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



175
176
177
178
179
180
# File 'lib/rubygems/dependency_list.rb', line 175

def remove_specs_unsatisfied_by(dependencies)
  specs.reject! do |spec|
    dep = dependencies[spec.name]
    dep and not dep.requirement.satisfied_by? spec.version
  end
end

#spec_predecessorsObject

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



193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
# File 'lib/rubygems/dependency_list.rb', line 193

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
          result[spec] << other
        end
      end
    end
  end

  result
end

#tsort_each_child(node) ⇒ Object



217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
# File 'lib/rubygems/dependency_list.rb', line 217

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
        yield spec
        break
      end
    end
  end
end

#tsort_each_node(&block) ⇒ Object



213
214
215
# File 'lib/rubygems/dependency_list.rb', line 213

def tsort_each_node(&block)
  @specs.each(&block)
end

#why_not_ok?(quick = false) ⇒ Boolean

Returns:

  • (Boolean)


117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
# File 'lib/rubygems/dependency_list.rb', line 117

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? do |installed_spec|
        dep.name == installed_spec.name and
          dep.requirement.satisfied_by? installed_spec.version
      end

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

  unsatisfied
end