read without size always returns a String.

Author: ioquatix

lib/io/stream/readable.rb

@@ -83,6 +83,17 @@ def read(size = nil, buffer = nil)
 				until @done
 					fill_read_buffer
 				end
+				
+				if buffer
+					buffer.replace(@read_buffer)
+					@read_buffer.clear
+				else
+					buffer = @read_buffer
+					@read_buffer = StringBuffer.new
+				end
+				
+				# Read without size always returns a non-nil value, even if it is an empty string.
+				return buffer
 			end
 
 			return consume_read_buffer(size, buffer)

releases.md

@@ -1,5 +1,9 @@
 # Releases
 
+## Unreleased
+
+  - Fix EOF behavior to match Ruby IO semantics: `read()` returns empty string `""` at EOF while `read(size)` returns `nil` at EOF.
+
 ## v0.9.0
 
   - Add support for `buffer` parameter in `read`, `read_exactly`, and `read_partial` methods to allow reading into a provided buffer.

test/io/stream/buffered.rb

@@ -714,7 +714,7 @@ def before
 	with "#close" do
 		it "should close the stream" do
 			server.close
-			expect(client.read).to be_nil
+			expect(client.read).to be == ""
 
 			expect(server.closed?).to be_truthy
 			expect(client.closed?).to be_falsey