diff --git a/src/libstd/io/mod.rs b/src/libstd/io/mod.rs index c38d52161c9..5e810926ee4 100644 --- a/src/libstd/io/mod.rs +++ b/src/libstd/io/mod.rs @@ -669,6 +669,11 @@ impl Take { impl Read for Take { fn read(&mut self, buf: &mut [u8]) -> Result { + // Don't call into inner reader at all at EOF because it may still block + if self.limit == 0 { + return Ok(0); + } + let max = cmp::min(buf.len() as u64, self.limit) as usize; let n = try!(self.inner.read(&mut buf[..max])); self.limit -= n as u64; @@ -846,6 +851,7 @@ impl Iterator for Lines { mod tests { use prelude::v1::*; use io::prelude::*; + use io; use super::Cursor; #[test] @@ -943,4 +949,18 @@ mod tests { let mut v = String::new(); assert!(c.read_to_string(&mut v).is_err()); } + + #[test] + fn take_eof() { + struct R; + + impl Read for R { + fn read(&mut self, buf: &mut [u8]) -> io::Result { + Err(io::Error::new(io::ErrorKind::Other, "", None)) + } + } + + let mut buf = [0; 1]; + assert_eq!(Ok(0), R.take(0).read(&mut buf)); + } }