ActiveSupport::Dependencies::WatchStack

    # File lib/active_support/dependencies.rb, line 81
81:       def initialize
82:         @watching = []
83:         super { |h,k| h[k] = [] }
84:       end

     # File lib/active_support/dependencies.rb, line 87
 87:       def new_constants
 88:         constants = []
 89: 
 90:         # Grab the list of namespaces that we're looking for new constants under
 91:         @watching.last.each do |namespace|
 92:           # Retrieve the constants that were present under the namespace when watch_modules
 93:           # was originally called
 94:           original_constants = self[namespace].last
 95: 
 96:           mod = Inflector.constantize(namespace) if Dependencies.qualified_const_defined?(namespace)
 97:           next unless mod.is_a?(Module)
 98: 
 99:           # Get a list of the constants that were added
100:           new_constants = mod.local_constant_names - original_constants
101: 
102:           # self[namespace] returns an Array of the constants that are being evaluated
103:           # for that namespace. For instance, if parent.rb requires child.rb, the first
104:           # element of self[Object] will be an Array of the constants that were present
105:           # before parent.rb was required. The second element will be an Array of the
106:           # constants that were present before child.rb was required.
107:           self[namespace].each do |namespace_constants|
108:             namespace_constants.concat(new_constants)
109:           end
110: 
111:           # Normalize the list of new constants, and add them to the list we will return
112:           new_constants.each do |suffix|
113:             constants << ([namespace, suffix] - ["Object"]).join("::")
114:           end
115:         end
116:         constants
117:       ensure
118:         # A call to new_constants is always called after a call to watch_modules
119:         pop_modules(@watching.pop)
120:       end

     # File lib/active_support/dependencies.rb, line 136
136:       def pop_modules(modules)
137:         modules.each { |mod| self[mod].pop }
138:       end

     # File lib/active_support/dependencies.rb, line 123
123:       def watch_namespaces(namespaces)
124:         watching = []
125:         namespaces.map do |namespace|
126:           module_name = Dependencies.to_constant_name(namespace)
127:           original_constants = Dependencies.qualified_const_defined?(module_name) ?
128:             Inflector.constantize(module_name).local_constant_names : []
129: 
130:           watching << module_name
131:           self[module_name] << original_constants
132:         end
133:         @watching << watching
134:       end