tee_input: simplify conditional for writing to temporary file

It's rare to have an empty string returned by `read` since it
requires a length argument of zero (careless) or nil (danger!
OOM!).  Lets not try to optimize away a method dispatch in this
case by checking .size (optimized instruction in YARV).

Ruby IO#write already treats writing an empty string as a noop,
so no syscall is saved.

n.b.  `gets` can return an empty string, too, but that's also
dangerous w.r.t. memory usage on untrusted input.

1 files changed, 1 insertions, 3 deletions

diff --git a/lib/yahns/tee_input.rb b/lib/yahns/tee_input.rb
index 93ec148..90c8fd6 100644
--- a/lib/yahns/tee_input.rb
+++ b/lib/yahns/tee_input.rb
@@ -104,9 +104,7 @@ class Yahns::TeeInput < Yahns::StreamInput # :nodoc:
   end
 
   def tee(buffer)
-    if buffer && buffer.size > 0
-      @tmp.write(buffer)
-    end
+    @tmp.write(buffer) if buffer
     buffer
   end