Add ability to use named arguments when invoking a task

lib/rake/application.rb

@@ -161,25 +161,62 @@ def invoke_task(task_string) # :nodoc:
     end
 
     def parse_task_string(string) # :nodoc:
-      /^([^\[]+)(?:\[(.*)\])$/ =~ string.to_s
+      case string.to_s
+      when /^([^\[]+)(?:\[(.*)\])$/ # [one, two]
+        name = $1
+        args = parse_positional_args_string($2)
+      when /^([^\{]+)(?:\{(.*)\})$/ # [key: value]
+        name = $1
+        args = parse_named_args_string($2)
+        args = args.empty? ? [] : [args]
+      else
+        name = string
+        args = []
+      end
 
-      name           = $1
-      remaining_args = $2
+      return name, args
+    end
 
-      return string, [] unless name
-      return name,   [] if     remaining_args.empty?
+    def parse_positional_args_string(string) # :nodoc:
+      return [] if string.empty?
 
       args = []
+      remaining_args = string
 
       begin
-        /\s*((?:[^\\,]|\\.)*?)\s*(?:,\s*(.*))?$/ =~ remaining_args
+        /\s*(?<arg>(?:[^\\,]|\\.)*?)\s*(?:,\s*(?<remaining_args>.*))?$/ =~ remaining_args
 
-        remaining_args = $2
-        args << $1.gsub(/\\(.)/, '\1')
+        args << arg.gsub(/\\(.)/, '\1')
       end while remaining_args
 
-      return name, args
+      args
+    end
+    private :parse_positional_args_string
+
+    def parse_named_args_string(string) # :nodoc:
+      return {} if string.empty?
+
+      args = {}
+      remaining_args = string
+
+      begin
+        /
+          \s*
+          (?<arg_name>(?:[^\\:]|\\.)*?)
+          \s*:\s*
+          (?<arg_value>(?:[^\\,]|\\.)*?)
+          \s*
+          (?:,\s*(?<remaining_args>.*))?
+        $/x =~ remaining_args
+
+        arg_name = arg_name.gsub(/\\(.)/, '\1').to_sym
+        arg_value = arg_value.gsub(/\\(.)/, '\1')
+        args[arg_name] = arg_value
+      end while remaining_args
+
+      args
     end
+    private :parse_named_args_string
 
     # Provide standard exception handling for the given block.
     def standard_exception_handling # :nodoc:

lib/rake/task.rb

@@ -184,6 +184,11 @@ def clear_args
 
     # Invoke the task if it is needed.  Prerequisites are invoked first.
     def invoke(*args)
+      if args.first.is_a?(Hash)
+        opts = args.first
+        args = arg_names.map { |arg_name| opts[arg_name.to_sym] }
+      end
+
       task_args = TaskArguments.new(arg_names, args)
       invoke_with_call_chain(task_args, InvocationChain::EMPTY)
     end

test/test_rake_task_argument_parsing.rb

@@ -18,42 +18,76 @@ def test_empty_args
     name, args = @app.parse_task_string("name[]")
     assert_equal "name", name
     assert_equal [], args
+
+    name, args = @app.parse_task_string("name{}")
+    assert_equal "name", name
+    assert_equal [], args
   end
 
   def test_one_argument
     name, args = @app.parse_task_string("name[one]")
     assert_equal "name", name
     assert_equal ["one"], args
+
+    name, args = @app.parse_task_string("name{one:1}")
+    assert_equal "name", name
+    assert_equal [{one: "1"}], args
   end
 
   def test_two_arguments
     name, args = @app.parse_task_string("name[one,two]")
     assert_equal "name", name
     assert_equal ["one", "two"], args
+
+    name, args = @app.parse_task_string("name{one:1,two:2}")
+    assert_equal "name", name
+    assert_equal [{one: "1", two: "2"}], args
   end
 
   def test_can_handle_spaces_between_args
     name, args = @app.parse_task_string("name[one, two,\tthree , \tfour]")
     assert_equal "name", name
     assert_equal ["one", "two", "three", "four"], args
+
+    name, args = @app.parse_task_string("name{one: 1, two:2,\tthree : 3, \tfour:4}")
+    assert_equal "name", name
+    assert_equal [{one: "1", two: "2", three: "3", four: "4"}], args
   end
 
   def test_can_handle_spaces_between_all_args
     name, args = @app.parse_task_string("name[ one , two ,\tthree , \tfour ]")
     assert_equal "name", name
     assert_equal ["one", "two", "three", "four"], args
+
+    name, args = @app.parse_task_string("name{ one : 1, two:2 ,\tthree  :  3 , \tfour: 4 }")
+    assert_equal "name", name
+    assert_equal [{one: "1", two: "2", three: "3", four: "4"}], args
   end
 
   def test_keeps_embedded_spaces
     name, args = @app.parse_task_string("name[a one ana, two]")
     assert_equal "name", name
     assert_equal ["a one ana", "two"], args
+
+    name, args = @app.parse_task_string("name{a one ana: has value, two:2}")
+    assert_equal "name", name
+    assert_equal [{:"a one ana" => "has value", two: "2"}], args
   end
 
   def test_can_handle_commas_in_args
     name, args = @app.parse_task_string("name[one, two, three_a\\, three_b, four]")
     assert_equal "name", name
     assert_equal ["one", "two", "three_a, three_b", "four"], args
+
+    name, args = @app.parse_task_string("name{one:1, two:2, three_a\\, three_b:3, four:4}")
+    assert_equal "name", name
+    assert_equal [{one: "1", two: "2", :"three_a, three_b" => "3", four: "4"}], args
+  end
+
+  def test_can_handle_colons_in_named_args
+    name, args = @app.parse_task_string("name{one:1, two:2, three_a\\: three_b:3, four:4}")
+    assert_equal "name", name
+    assert_equal [{one: "1", two: "2", :"three_a: three_b" => "3", four: "4"}], args
   end
 
   def test_treat_blank_arg_as_empty_string

test/test_rake_task_with_arguments.rb

@@ -60,6 +60,18 @@ def test_tasks_can_access_arguments_as_hash
     t.invoke(1, 2, 3)
   end
 
+  def test_arguments_passed_as_hash
+    t = task :t, :a, :b do |tt, args|
+      assert_equal({ a: 1, b: 2 }, args.to_hash)
+      assert_equal 1, args[:a]
+      assert_equal 2, args[:b]
+      assert_equal 1, args.a
+      assert_equal 2, args.b
+    end
+
+    t.invoke({a: 1, b: 2})
+  end
+
   def test_actions_of_various_arity_are_ok_with_args
     notes = []
     t = task(:t, :x) do