1 files changed, 60 insertions, 0 deletions
diff --git a/spec/ruby/core/io/initialize_spec.rb b/spec/ruby/core/io/initialize_spec.rb
new file mode 100644
index 0000000000..3425e5ac37
--- /dev/null
+++ b/spec/ruby/core/io/initialize_spec.rb
@@ -0,0 +1,60 @@
+require_relative '../../spec_helper'
+require_relative 'fixtures/classes'
+
+describe "IO#initialize" do
+  before :each do
+    @name = tmp("io_initialize.txt")
+    @io = IO.new(new_fd(@name))
+    @fd = @io.fileno
+  end
+
+  after :each do
+    @io.close if @io
+    rm_r @name
+  end
+
+  it "reassociates the IO instance with the new descriptor when passed an Integer" do
+    fd = new_fd @name, "r:utf-8"
+    @io.send :initialize, fd, 'r'
+    @io.fileno.should == fd
+  end
+
+  it "calls #to_int to coerce the object passed as an fd" do
+    obj = mock('fileno')
+    fd = new_fd @name, "r:utf-8"
+    obj.should_receive(:to_int).and_return(fd)
+    @io.send :initialize, obj, 'r'
+    @io.fileno.should == fd
+  end
+
+  it "accepts options as keyword arguments" do
+    fd = new_fd @name, "w:utf-8"
+
+    @io.send(:initialize, fd, "w", flags: File::CREAT)
+    @io.fileno.should == fd
+
+    -> {
+      @io.send(:initialize, fd, "w", {flags: File::CREAT})
+    }.should.raise(ArgumentError, "wrong number of arguments (given 3, expected 1..2)")
+  end
+
+  it "raises a TypeError when passed an IO" do
+    -> { @io.send :initialize, STDOUT, 'w' }.should.raise(TypeError)
+  end
+
+  it "raises a TypeError when passed nil" do
+    -> { @io.send :initialize, nil, 'w' }.should.raise(TypeError)
+  end
+
+  it "raises a TypeError when passed a String" do
+    -> { @io.send :initialize, "4", 'w' }.should.raise(TypeError)
+  end
+
+  it "raises IOError on closed stream" do
+    -> { @io.send :initialize, IOSpecs.closed_io.fileno }.should.raise(IOError)
+  end
+
+  it "raises an Errno::EBADF when given an invalid file descriptor" do
+    -> { @io.send :initialize, -1, 'w' }.should.raise(Errno::EBADF)
+  end
+end