diff --git a/library/std/src/io/util.rs b/library/std/src/io/util.rs index cb3f864fd4e1e..17178b4a64147 100644 --- a/library/std/src/io/util.rs +++ b/library/std/src/io/util.rs @@ -68,6 +68,38 @@ impl Read for Empty { fn read_buf(&mut self, _cursor: BorrowedCursor<'_>) -> io::Result<()> { Ok(()) } + + #[inline] + fn read_vectored(&mut self, _bufs: &mut [IoSliceMut<'_>]) -> io::Result { + Ok(0) + } + + #[inline] + fn is_read_vectored(&self) -> bool { + // Do not force `Chain` or `Chain` to use vectored + // reads, unless the other reader is vectored. + false + } + + #[inline] + fn read_exact(&mut self, buf: &mut [u8]) -> io::Result<()> { + if !buf.is_empty() { Err(io::Error::READ_EXACT_EOF) } else { Ok(()) } + } + + #[inline] + fn read_buf_exact(&mut self, cursor: BorrowedCursor<'_>) -> io::Result<()> { + if cursor.capacity() != 0 { Err(io::Error::READ_EXACT_EOF) } else { Ok(()) } + } + + #[inline] + fn read_to_end(&mut self, _buf: &mut Vec) -> io::Result { + Ok(0) + } + + #[inline] + fn read_to_string(&mut self, _buf: &mut String) -> io::Result { + Ok(0) + } } #[stable(feature = "rust1", since = "1.0.0")] impl BufRead for Empty { @@ -75,20 +107,44 @@ impl BufRead for Empty { fn fill_buf(&mut self) -> io::Result<&[u8]> { Ok(&[]) } + #[inline] fn consume(&mut self, _n: usize) {} + + #[inline] + fn has_data_left(&mut self) -> io::Result { + Ok(false) + } + + #[inline] + fn read_until(&mut self, _byte: u8, _buf: &mut Vec) -> io::Result { + Ok(0) + } + + #[inline] + fn skip_until(&mut self, _byte: u8) -> io::Result { + Ok(0) + } + + #[inline] + fn read_line(&mut self, _buf: &mut String) -> io::Result { + Ok(0) + } } #[stable(feature = "empty_seek", since = "1.51.0")] impl Seek for Empty { + #[inline] fn seek(&mut self, _pos: SeekFrom) -> io::Result { Ok(0) } + #[inline] fn stream_len(&mut self) -> io::Result { Ok(0) } + #[inline] fn stream_position(&mut self) -> io::Result { Ok(0) } @@ -119,6 +175,21 @@ impl Write for Empty { true } + #[inline] + fn write_all(&mut self, _buf: &[u8]) -> io::Result<()> { + Ok(()) + } + + #[inline] + fn write_all_vectored(&mut self, _bufs: &mut [IoSlice<'_>]) -> io::Result<()> { + Ok(()) + } + + #[inline] + fn write_fmt(&mut self, _args: fmt::Arguments<'_>) -> io::Result<()> { + Ok(()) + } + #[inline] fn flush(&mut self) -> io::Result<()> { Ok(()) @@ -143,6 +214,21 @@ impl Write for &Empty { true } + #[inline] + fn write_all(&mut self, _buf: &[u8]) -> io::Result<()> { + Ok(()) + } + + #[inline] + fn write_all_vectored(&mut self, _bufs: &mut [IoSlice<'_>]) -> io::Result<()> { + Ok(()) + } + + #[inline] + fn write_fmt(&mut self, _args: fmt::Arguments<'_>) -> io::Result<()> { + Ok(()) + } + #[inline] fn flush(&mut self) -> io::Result<()> { Ok(()) @@ -302,6 +388,21 @@ impl Write for Sink { true } + #[inline] + fn write_all(&mut self, _buf: &[u8]) -> io::Result<()> { + Ok(()) + } + + #[inline] + fn write_all_vectored(&mut self, _bufs: &mut [IoSlice<'_>]) -> io::Result<()> { + Ok(()) + } + + #[inline] + fn write_fmt(&mut self, _args: fmt::Arguments<'_>) -> io::Result<()> { + Ok(()) + } + #[inline] fn flush(&mut self) -> io::Result<()> { Ok(()) @@ -326,6 +427,21 @@ impl Write for &Sink { true } + #[inline] + fn write_all(&mut self, _buf: &[u8]) -> io::Result<()> { + Ok(()) + } + + #[inline] + fn write_all_vectored(&mut self, _bufs: &mut [IoSlice<'_>]) -> io::Result<()> { + Ok(()) + } + + #[inline] + fn write_fmt(&mut self, _args: fmt::Arguments<'_>) -> io::Result<()> { + Ok(()) + } + #[inline] fn flush(&mut self) -> io::Result<()> { Ok(()) diff --git a/library/std/src/io/util/tests.rs b/library/std/src/io/util/tests.rs index 0599a881af179..d0f106d7af416 100644 --- a/library/std/src/io/util/tests.rs +++ b/library/std/src/io/util/tests.rs @@ -1,14 +1,51 @@ +use crate::fmt; use crate::io::prelude::*; -use crate::io::{BorrowedBuf, Empty, Repeat, SeekFrom, Sink, empty, repeat, sink}; +use crate::io::{ + BorrowedBuf, Empty, ErrorKind, IoSlice, IoSliceMut, Repeat, SeekFrom, Sink, empty, repeat, sink, +}; use crate::mem::MaybeUninit; +struct ErrorDisplay; + +impl fmt::Display for ErrorDisplay { + fn fmt(&self, _f: &mut fmt::Formatter<'_>) -> fmt::Result { + Err(fmt::Error) + } +} + +struct PanicDisplay; + +impl fmt::Display for PanicDisplay { + fn fmt(&self, _f: &mut fmt::Formatter<'_>) -> fmt::Result { + panic!() + } +} + +#[track_caller] +fn test_sinking(mut w: W) { + assert_eq!(w.write(&[]).unwrap(), 0); + assert_eq!(w.write(&[0]).unwrap(), 1); + assert_eq!(w.write(&[0; 1024]).unwrap(), 1024); + w.write_all(&[]).unwrap(); + w.write_all(&[0]).unwrap(); + w.write_all(&[0; 1024]).unwrap(); + let mut bufs = + [IoSlice::new(&[]), IoSlice::new(&[0]), IoSlice::new(&[0; 1024]), IoSlice::new(&[])]; + assert!(w.is_write_vectored()); + assert_eq!(w.write_vectored(&[]).unwrap(), 0); + assert_eq!(w.write_vectored(&bufs).unwrap(), 1025); + w.write_all_vectored(&mut []).unwrap(); + w.write_all_vectored(&mut bufs).unwrap(); + assert!(w.flush().is_ok()); + assert_eq!(w.by_ref().write(&[0; 1024]).unwrap(), 1024); + // Ignores fmt arguments + w.write_fmt(format_args!("{}", ErrorDisplay)).unwrap(); + w.write_fmt(format_args!("{}", PanicDisplay)).unwrap(); +} + #[test] fn sink_sinks() { - let mut s = sink(); - assert_eq!(s.write(&[]).unwrap(), 0); - assert_eq!(s.write(&[0]).unwrap(), 1); - assert_eq!(s.write(&[0; 1024]).unwrap(), 1024); - assert_eq!(s.by_ref().write(&[0; 1024]).unwrap(), 1024); + test_sinking(sink()); } #[test] @@ -19,6 +56,21 @@ fn empty_reads() { assert_eq!(e.read(&mut [0; 1024]).unwrap(), 0); assert_eq!(Read::by_ref(&mut e).read(&mut [0; 1024]).unwrap(), 0); + e.read_exact(&mut []).unwrap(); + assert_eq!(e.read_exact(&mut [0]).unwrap_err().kind(), ErrorKind::UnexpectedEof); + assert_eq!(e.read_exact(&mut [0; 1024]).unwrap_err().kind(), ErrorKind::UnexpectedEof); + + assert!(!e.is_read_vectored()); + assert_eq!(e.read_vectored(&mut []).unwrap(), 0); + let (mut buf1, mut buf1024) = ([0], [0; 1024]); + let bufs = &mut [ + IoSliceMut::new(&mut []), + IoSliceMut::new(&mut buf1), + IoSliceMut::new(&mut buf1024), + IoSliceMut::new(&mut []), + ]; + assert_eq!(e.read_vectored(bufs).unwrap(), 0); + let buf: &mut [MaybeUninit<_>] = &mut []; let mut buf: BorrowedBuf<'_> = buf.into(); e.read_buf(buf.unfilled()).unwrap(); @@ -42,6 +94,47 @@ fn empty_reads() { Read::by_ref(&mut e).read_buf(buf.unfilled()).unwrap(); assert_eq!(buf.len(), 0); assert_eq!(buf.init_len(), 0); + + let buf: &mut [MaybeUninit<_>] = &mut []; + let mut buf: BorrowedBuf<'_> = buf.into(); + e.read_buf_exact(buf.unfilled()).unwrap(); + assert_eq!(buf.len(), 0); + assert_eq!(buf.init_len(), 0); + + let buf: &mut [_] = &mut [MaybeUninit::uninit()]; + let mut buf: BorrowedBuf<'_> = buf.into(); + assert_eq!(e.read_buf_exact(buf.unfilled()).unwrap_err().kind(), ErrorKind::UnexpectedEof); + assert_eq!(buf.len(), 0); + assert_eq!(buf.init_len(), 0); + + let buf: &mut [_] = &mut [MaybeUninit::uninit(); 1024]; + let mut buf: BorrowedBuf<'_> = buf.into(); + assert_eq!(e.read_buf_exact(buf.unfilled()).unwrap_err().kind(), ErrorKind::UnexpectedEof); + assert_eq!(buf.len(), 0); + assert_eq!(buf.init_len(), 0); + + let buf: &mut [_] = &mut [MaybeUninit::uninit(); 1024]; + let mut buf: BorrowedBuf<'_> = buf.into(); + assert_eq!( + Read::by_ref(&mut e).read_buf_exact(buf.unfilled()).unwrap_err().kind(), + ErrorKind::UnexpectedEof, + ); + assert_eq!(buf.len(), 0); + assert_eq!(buf.init_len(), 0); + + let mut buf = Vec::new(); + assert_eq!(e.read_to_end(&mut buf).unwrap(), 0); + assert_eq!(buf, vec![]); + let mut buf = vec![1, 2, 3]; + assert_eq!(e.read_to_end(&mut buf).unwrap(), 0); + assert_eq!(buf, vec![1, 2, 3]); + + let mut buf = String::new(); + assert_eq!(e.read_to_string(&mut buf).unwrap(), 0); + assert_eq!(buf, ""); + let mut buf = "hello".to_owned(); + assert_eq!(e.read_to_string(&mut buf).unwrap(), 0); + assert_eq!(buf, "hello"); } #[test] @@ -66,11 +159,7 @@ fn empty_seeks() { #[test] fn empty_sinks() { - let mut e = empty(); - assert_eq!(e.write(&[]).unwrap(), 0); - assert_eq!(e.write(&[0]).unwrap(), 1); - assert_eq!(e.write(&[0; 1024]).unwrap(), 1024); - assert_eq!(Write::by_ref(&mut e).write(&[0; 1024]).unwrap(), 1024); + test_sinking(empty()); } #[test] diff --git a/tests/ui/write-fmt-errors.rs b/tests/ui/write-fmt-errors.rs index 1dafb9a784b3a..b48fa3f11ccb1 100644 --- a/tests/ui/write-fmt-errors.rs +++ b/tests/ui/write-fmt-errors.rs @@ -4,7 +4,7 @@ #![feature(io_error_uncategorized)] use std::fmt; -use std::io::{self, Error, Write, sink}; +use std::io::{self, Error, Write}; use std::panic::catch_unwind; struct ErrorDisplay; @@ -33,7 +33,7 @@ fn main() { assert!(res.is_err(), "writer error did not propagate"); // Test that the error from the formatter is detected. - let res = catch_unwind(|| write!(sink(), "{} {} {}", 1, ErrorDisplay, "bar")); + let res = catch_unwind(|| write!(vec![], "{} {} {}", 1, ErrorDisplay, "bar")); let err = res.expect_err("formatter error did not lead to panic").downcast::<&str>().unwrap(); assert!( err.contains("formatting trait implementation returned an error"),