test/io_test.rb in bindata-2.2.0 vs test/io_test.rb in bindata-2.3.0

@@ -132,12 +132,61 @@
     io.with_buffer(10) do
       io.seekbytes(15)
     end
     io.offset.must_equal(10)
   end
+
+  it "restricts large -ve seeks" do
+    io.readbytes(2)
+    io.with_buffer(10) do
+      io.seekbytes(-1)
+      io.offset.must_equal(2)
+    end
+  end
 end
 
+describe BinData::IO::Write, "writing to non seekable stream" do
+  before do
+    @rd, @wr = IO::pipe
+    @io = BinData::IO::Write.new(@wr)
+  end
+
+  after do
+    @rd.close
+    @wr.close
+  end
+
+  it "writes data" do
+    @io.writebytes("1234567890")
+    @rd.read(10).must_equal "1234567890"
+  end
+
+  it "has correct offset" do
+    @io.writebytes("1234567890")
+    @io.offset.must_equal 10
+  end
+
+  it "does not seek backwards" do
+    @io.writebytes("1234567890")
+    lambda {
+      @io.seekbytes(-5)
+    }.must_raise IOError
+  end
+
+  it "does not seek forwards" do
+    lambda {
+      @io.seekbytes(5)
+    }.must_raise IOError
+  end
+
+  it "#num_bytes_remaining raises IOError" do
+    lambda {
+      @io.num_bytes_remaining
+    }.must_raise IOError
+  end
+end
+
 describe BinData::IO::Write, "when writing" do
   let(:stream) { StringIO.new }
   let(:io) { BinData::IO::Write.new(stream) }
 
   it "raises error when io is BinData::IO" do
@@ -202,9 +251,24 @@
       end
       io.writebytes "de"
     end
 
     stream.value.must_equal "abc\0\0de\0\0\0"
+  end
+
+  it "restricts large seeks" do
+    io.with_buffer(10) do
+      io.seekbytes(15)
+    end
+    io.offset.must_equal(10)
+  end
+
+  it "restricts large -ve seeks" do
+    io.writebytes("12")
+    io.with_buffer(10) do
+      io.seekbytes(-1)
+      io.offset.must_equal(2)
+    end
   end
 end
 
 describe BinData::IO::Read, "reading bits in big endian" do
   let(:b1) { 0b1111_1010 }