#!/usr/bin/env rspec
# Copyright, 2012, by Samuel G. D. Williams. <http://www.codeotaku.com>
# 
# Permission is hereby granted, free of charge, to any person obtaining a copy
# of this software and associated documentation files (the "Software"), to deal
# in the Software without restriction, including without limitation the rights
# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
# copies of the Software, and to permit persons to whom the Software is
# furnished to do so, subject to the following conditions:
# 
# The above copyright notice and this permission notice shall be included in
# all copies or substantial portions of the Software.
# 
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
# THE SOFTWARE.

require 'build/graph/node'
require 'build/graph/walker'
require 'build/graph/task'
require 'build/files/glob'

RSpec.describe Build::Graph::Walker do
	it "can generate the same output from multiple tasks" do
		test_glob = Build::Files::Glob.new(__dir__, "*.rb")
		listing_output = Build::Files::Paths.directory(__dir__, ["listing.txt"])
		
		node_a = Build::Graph::Node.new(test_glob, listing_output, "a")
		node_b = Build::Graph::Node.new(Build::Files::Paths::NONE, listing_output, "b")
		
		sequence = []
		
		# A walker runs repeatedly, updating tasks which have been marked as dirty.
		walker = Build::Graph::Walker.new do |walker, node|
			task = Build::Graph::Task.new(walker, node)
			
			task.visit do
				if node.process == "a"
					task.invoke(node_b)
				end
				
				node.outputs.each do |output|
					output.touch
				end
				sequence << node.process
			end
		end
		
		edge = double()
		walker.outputs[listing_output.first.to_s] ||= [edge]
		expect(edge).to receive(:traverse)
		
		walker.update([node_a, node_a])
		
		expect(walker.tasks.count).to be == 2
		expect(walker.failed_tasks.count).to be == 0
		expect(sequence).to be == ['b', 'a']
	end
	
	it "should be unique" do
		test_glob = Build::Files::Glob.new(__dir__, "*.rb")
		listing_output = Build::Files::Paths.directory(__dir__, ["listing.txt"])
		
		node_a = Build::Graph::Node.new(test_glob, listing_output, "a")
		node_b = Build::Graph::Node.new(listing_output, Build::Files::Paths::NONE, "b")
		
		sequence = []
		
		# A walker runs repeatedly, updating tasks which have been marked as dirty.
		walker = Build::Graph::Walker.new do |walker, node|
			task = Build::Graph::Task.new(walker, node)
			
			task.visit do
				node.outputs.each do |output|
					output.touch
				end
				sequence << node.process
			end
		end
		
		walker.update([node_a, node_b])
		
		expect(walker.tasks.count).to be == 2
		expect(walker.failed_tasks.count).to be == 0
		expect(sequence).to be == ['a', 'b']
	end
	
	it "should cascade failure" do
		test_glob = Build::Files::Glob.new(__dir__, "*.rb")
		listing_output = Build::Files::Paths.directory(__dir__, ["listing.txt"])
		summary_output = Build::Files::Paths.directory(__dir__, ["summary.txt"])
		
		node_a = Build::Graph::Node.new(test_glob, listing_output, "a")
		node_b = Build::Graph::Node.new(listing_output, summary_output, "b")
		
		# A walker runs repeatedly, updating tasks which have been marked as dirty.
		walker = Build::Graph::Walker.new do |walker, node|
			task = Build::Graph::Task.new(walker, node)
			
			task.visit do
				if node.process == 'a'
					raise Build::Graph::TransientError.new('Test Failure')
				end
			end
		end
		
		walker.update([node_a, node_b])
		
		expect(walker.tasks.count).to be == 2
		expect(walker.failed_tasks.count).to be == 2
		expect(listing_output).to be_intersect walker.failed_outputs
		expect(summary_output).to be_intersect walker.failed_outputs
		
		walker.clear_failed
		
		expect(walker.tasks.count).to be == 0
		expect(walker.failed_tasks.count).to be == 0
	end
end