ruby--ruby/spec/ruby/library/stringio/print_spec.rb

require_relative '../../spec_helper'
require_relative 'fixtures/classes'

describe "StringIO#print" do
  before :each do
    @io = StringIO.new('example')
  end

  it "prints $_ when passed no arguments" do
    $_ = nil
    @io.print
    @io.string.should == "example"

    $_ = "blah"
    @io.print
    @io.string.should == "blahple"
  end

  it "prints the passed arguments to self" do
    @io.print(5, 6, 7, 8)
    @io.string.should == "5678ple"
  end

  it "tries to convert the passed Object to a String using #to_s" do
    obj = mock("to_s")
    obj.should_receive(:to_s).and_return("to_s")
    @io.print(obj)
    @io.string.should == "to_sple"
  end

  it "returns nil" do
    @io.print(1, 2, 3).should be_nil
  end

  it "pads self with \\000 when the current position is after the end" do
    @io.pos = 10
    @io.print(1, 2, 3)
    @io.string.should == "example\000\000\000123"
  end

  it "honors the output record separator global" do
    old_rs = $\
    suppress_warning {$\ = 'x'}

    begin
      @io.print(5, 6, 7, 8)
      @io.string.should == '5678xle'
    ensure
      suppress_warning {$\ = old_rs}
    end
  end

  it "updates the current position" do
    @io.print(1, 2, 3)
    @io.pos.should eql(3)

    @io.print(1, 2, 3)
    @io.pos.should eql(6)
  end

  it "correctly updates the current position when honoring the output record separator global" do
    old_rs = $\
    suppress_warning {$\ = 'x'}

    begin
      @io.print(5, 6, 7, 8)
      @io.pos.should eql(5)
    ensure
      suppress_warning {$\ = old_rs}
    end
  end
end

describe "StringIO#print when in append mode" do
  before :each do
    @io = StringIO.new("example", "a")
  end

  it "appends the passed argument to the end of self" do
    @io.print(", just testing")
    @io.string.should == "example, just testing"

    @io.print(" and more testing")
    @io.string.should == "example, just testing and more testing"
  end

  it "correctly updates self's position" do
    @io.print(", testing")
    @io.pos.should eql(16)
  end
end

describe "StringIO#print when self is not writable" do
  it "raises an IOError" do
    io = StringIO.new("test", "r")
    -> { io.print("test") }.should raise_error(IOError)

    io = StringIO.new("test")
    io.close_write
    -> { io.print("test") }.should raise_error(IOError)
  end
end