# module Rake::TaskManager

The TaskManager module is a mixin for managing tasks.

### Attributes

last_description[RW]

Track the last comment made in the Rakefile.

### Public Instance Methods

[](task_name, scopes=nil) click to toggle source

Find a matching task for `task_name`.

    # File lib/rake/task_manager.rb, line 54
    def [](task_name, scopes=nil)
      task_name = task_name.to_s
      self.lookup(task_name, scopes) or
        enhance_with_matching_rule(task_name) or
        synthesize_file_task(task_name) or
        fail generate_message_for_undefined_task(task_name)
    end

clear() click to toggle source

Clear all tasks in this application.

    # File lib/rake/task_manager.rb, line 174
    def clear
      @tasks.clear
      @rules.clear
    end

current_scope() click to toggle source

Return the list of scope names currently active in the task manager.

    # File lib/rake/task_manager.rb, line 214
    def current_scope
      @scope
    end

enhance_with_matching_rule(task_name, level=0) click to toggle source

If a rule can be found that matches the task name, enhance the task with the prerequisites and actions from the rule. Set the source attribute of the task appropriately for the rule. Return the enhanced task or nil of no rule was found.

    # File lib/rake/task_manager.rb, line 144
    def enhance_with_matching_rule(task_name, level=0)
      fail Rake::RuleRecursionOverflowError,
        "Rule Recursion Too Deep" if level >= 16
      @rules.each do |pattern, args, extensions, block|
        if pattern && pattern.match(task_name)
          task = attempt_rule(task_name, pattern, args, extensions, block, level)
          return task if task
        end
      end
      nil
    rescue Rake::RuleRecursionOverflowError => ex
      ex.add_target(task_name)
      fail ex
    end

generate_did_you_mean_suggestions(task_name) click to toggle source

    # File lib/rake/task_manager.rb, line 67
    def generate_did_you_mean_suggestions(task_name)
      return "" unless defined?(::DidYouMean::SpellChecker)

      suggestions = ::DidYouMean::SpellChecker.new(dictionary: @tasks.keys).correct(task_name.to_s)
      if ::DidYouMean.respond_to?(:formatter)# did_you_mean v1.2.0 or later
        ::DidYouMean.formatter.message_for(suggestions)
      elsif defined?(::DidYouMean::Formatter) # before did_you_mean v1.2.0
        ::DidYouMean::Formatter.new(suggestions).to_s
      else
        ""
      end
    end

generate_message_for_undefined_task(task_name) click to toggle source

    # File lib/rake/task_manager.rb, line 62
    def generate_message_for_undefined_task(task_name)
      message = "Don't know how to build task '#{task_name}' (See the list of available tasks with `rake --tasks`)"
      message + generate_did_you_mean_suggestions(task_name)
    end

in_namespace(name) { |ns| ... } click to toggle source

Evaluate the block in a nested namespace named `name`. Create an anonymous namespace if `name` is nil.

    # File lib/rake/task_manager.rb, line 220
    def in_namespace(name)
      name ||= generate_name
      @scope = Scope.new(name, @scope)
      ns = NameSpace.new(self, @scope)
      yield(ns)
      ns
    ensure
      @scope = @scope.tail
    end

intern(task_class, task_name) click to toggle source

Lookup a task. Return an existing task if found, otherwise create a task of the current type.

    # File lib/rake/task_manager.rb, line 49
    def intern(task_class, task_name)
      @tasks[task_name.to_s] ||= task_class.new(task_name, self)
    end

lookup(task_name, initial_scope=nil) click to toggle source

Lookup a task, using scope and the scope hints in the task name. This method performs straight lookups without trying to synthesize file tasks or rules. Special scope names (e.g. '^') are recognized. If no scope argument is supplied, use the current scope. Return nil if the task cannot be found.

    # File lib/rake/task_manager.rb, line 184
    def lookup(task_name, initial_scope=nil)
      initial_scope ||= @scope
      task_name = task_name.to_s
      if task_name =~ /^rake:/
        scopes = Scope.make
        task_name = task_name.sub(/^rake:/, "")
      elsif task_name =~ /^(\^+)/
        scopes = initial_scope.trim($1.size)
        task_name = task_name.sub(/^(\^+)/, "")
      else
        scopes = initial_scope
      end
      lookup_in_scope(task_name, scopes)
    end

resolve_args(args) click to toggle source

Resolve the arguments for a task/rule. Returns a triplet of [task_name, arg_name_list, prerequisites].

    # File lib/rake/task_manager.rb, line 87
    def resolve_args(args)
      if args.last.is_a?(Hash)
        deps = args.pop
        resolve_args_with_dependencies(args, deps)
      else
        resolve_args_without_dependencies(args)
      end
    end

tasks() click to toggle source

List of all defined tasks in this application.

    # File lib/rake/task_manager.rb, line 160
    def tasks
      @tasks.values.sort_by { |t| t.name }
    end

tasks_in_scope(scope) click to toggle source

List of all the tasks defined in the given scope (and its sub-scopes).

    # File lib/rake/task_manager.rb, line 166
    def tasks_in_scope(scope)
      prefix = scope.path
      tasks.select { |t|
        /^#{prefix}:/ =~ t.name
      }
    end

### Private Instance Methods

add_location(task) click to toggle source

Add a location to the locations field of the given task.

    # File lib/rake/task_manager.rb, line 233
    def add_location(task)
      loc = find_location
      task.locations << loc if loc
      task
    end

attempt_rule(task_name, task_pattern, args, extensions, block, level) click to toggle source

Attempt to create a rule given the list of prerequisites.

    # File lib/rake/task_manager.rb, line 263
    def attempt_rule(task_name, task_pattern, args, extensions, block, level)
      sources = make_sources(task_name, task_pattern, extensions)
      prereqs = sources.map { |source|
        trace_rule level, "Attempting Rule #{task_name} => #{source}"
        if File.exist?(source) || Rake::Task.task_defined?(source)
          trace_rule level, "(#{task_name} => #{source} ... EXIST)"
          source
        elsif parent = enhance_with_matching_rule(source, level + 1)
          trace_rule level, "(#{task_name} => #{source} ... ENHANCE)"
          parent.name
        else
          trace_rule level, "(#{task_name} => #{source} ... FAIL)"
          return nil
        end
      }
      task = FileTask.define_task(task_name, { args => prereqs }, &block)
      task.sources = prereqs
      task
    end

find_location() click to toggle source

Find the location that called into the dsl layer.

    # File lib/rake/task_manager.rb, line 240
    def find_location
      locations = caller
      i = 0
      while locations[i]
        return locations[i + 1] if locations[i] =~ /rake\/dsl_definition.rb/
        i += 1
      end
      nil
    end

generate_name() click to toggle source

Generate an anonymous namespace name.

    # File lib/rake/task_manager.rb, line 251
    def generate_name
      @seed ||= 0
      @seed += 1
      "_anon_#{@seed}"
    end

get_description(task) click to toggle source

Return the current description, clearing it in the process.

    # File lib/rake/task_manager.rb, line 311
    def get_description(task)
      desc = @last_description
      @last_description = nil
      desc
    end

lookup_in_scope(name, scope) click to toggle source

Lookup the task name

    # File lib/rake/task_manager.rb, line 200
    def lookup_in_scope(name, scope)
      loop do
        tn = scope.path_with_task_name(name)
        task = @tasks[tn]
        return task if task
        break if scope.empty?
        scope = scope.tail
      end
      nil
    end

make_sources(task_name, task_pattern, extensions) click to toggle source

Make a list of sources from the list of file name extensions / translation procs.

    # File lib/rake/task_manager.rb, line 285
    def make_sources(task_name, task_pattern, extensions)
      result = extensions.map { |ext|
        case ext
        when /%/
          task_name.pathmap(ext)
        when %r{/}
          ext
        when /^\./
          source = task_name.sub(task_pattern, ext)
          source == ext ? task_name.ext(ext) : source
        when String
          ext
        when Proc, Method
          if ext.arity == 1
            ext.call(task_name)
          else
            ext.call
          end
        else
          fail "Don't know how to handle rule dependent: #{ext.inspect}"
        end
      }
      result.flatten
    end

resolve_args_without_dependencies(args) click to toggle source

Resolve task arguments for a task or rule when there are no dependencies declared.

The patterns recognized by this argument resolving function are:

    task :t
    task :t, [:a]

    # File lib/rake/task_manager.rb, line 104
    def resolve_args_without_dependencies(args)
      task_name = args.shift
      if args.size == 1 && args.first.respond_to?(:to_ary)
        arg_names = args.first.to_ary
      else
        arg_names = args
      end
      [task_name, arg_names, []]
    end