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

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

describe "StringIO#<< when passed [Object]" do
  before :each do
    @io = StringIO.new("example")
  end

  it "returns self" do
    (@io << "just testing").should equal(@io)
  end

  it "writes the passed argument onto self" do
    (@io << "just testing")
    @io.string.should == "just testing"
    (@io << " and more testing")
    @io.string.should == "just testing and more testing"
  end

  it "writes the passed argument at the current position" do
    @io.pos = 5
    @io << "<test>"
    @io.string.should == "examp<test>"
  end

  it "pads self with \\000 when the current position is after the end" do
    @io.pos = 15
    @io << "just testing"
    @io.string.should == "example\000\000\000\000\000\000\000\000just testing"
  end

  ruby_version_is ""..."2.7" do
    it "taints self's String when the passed argument is tainted" do
      (@io << "test".taint)
      @io.string.tainted?.should be_true
    end
  end

  ruby_version_is ""..."2.8" do
    it "does not taint self when the passed argument is tainted" do
      (@io << "test".taint)
      @io.tainted?.should be_false
    end
  end

  it "updates self's position" do
    @io << "test"
    @io.pos.should eql(4)
  end

  it "tries to convert the passed argument to a String using #to_s" do
    obj = mock("to_s")
    obj.should_receive(:to_s).and_return("Test")

    (@io << obj).string.should == "Testple"
  end
end

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

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

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

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

    @io.pos = 3
    (@io << " and more testing")
    @io.string.should == "example, just testing and more testing"
  end

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