require_relative '../../spec_helper'
require_relative 'shared/read'

platform_is_not :windows do
  describe 'ARGF.read_nonblock' do
    it_behaves_like :argf_read, :read_nonblock

    before do
      @file1_name = fixture(__FILE__, 'file1.txt')
      @file2_name = fixture(__FILE__, 'file2.txt')

      @file1 = File.read(@file1_name)
      @file2 = File.read(@file2_name)

      @chunk1 = File.read(@file1_name, 4)
      @chunk2 = File.read(@file2_name, 4)
    end

    it 'reads up to the given amount of bytes' do
      argf [@file1_name] do
        @argf.read_nonblock(4).should == @chunk1
      end
    end

    describe 'when using multiple files' do
      it 'reads up to the given amount of bytes from the first file' do
        argf [@file1_name, @file2_name] do
          @argf.read_nonblock(4).should == @chunk1
        end
      end

      it 'returns an empty String when reading after having read the first file in its entirety' do
        argf [@file1_name, @file2_name] do
          @argf.read_nonblock(File.size(@file1_name)).should == @file1
          @argf.read_nonblock(4).should == ''
        end
      end
    end

    it 'reads up to the given bytes from STDIN' do
      stdin = ruby_exe('print ARGF.read_nonblock(4)', :args => "< #{@file1_name}")

      stdin.should == @chunk1
    end

    it 'reads up to the given bytes from a file when a file and STDIN are present' do
      stdin = ruby_exe("print ARGF.read_nonblock(4)", :args => "#{@file1_name} - < #{@file2_name}")

      stdin.should == @chunk1
    end

    context "with STDIN" do
      before do
        @r, @w = IO.pipe
        @stdin = $stdin
        $stdin = @r
      end

      after do
        $stdin = @stdin
        @w.close
        @r.close unless @r.closed?
      end

      it 'raises IO::EAGAINWaitReadable when empty' do
        argf ['-'] do
          -> {
            @argf.read_nonblock(4)
          }.should raise_error(IO::EAGAINWaitReadable)
        end
      end

      it 'returns :wait_readable when the :exception is set to false' do
        argf ['-'] do
          @argf.read_nonblock(4, nil, exception: false).should == :wait_readable
        end
      end
    end
  end
end