diff options
Diffstat (limited to '')
-rw-r--r-- | library/std/src/fs.rs | 12 |
1 files changed, 7 insertions, 5 deletions
diff --git a/library/std/src/fs.rs b/library/std/src/fs.rs index f357d505f..286ad68fd 100644 --- a/library/std/src/fs.rs +++ b/library/std/src/fs.rs @@ -249,8 +249,9 @@ pub struct DirBuilder { pub fn read<P: AsRef<Path>>(path: P) -> io::Result<Vec<u8>> { fn inner(path: &Path) -> io::Result<Vec<u8>> { let mut file = File::open(path)?; - let mut bytes = Vec::new(); - file.read_to_end(&mut bytes)?; + let size = file.metadata().map(|m| m.len()).unwrap_or(0); + let mut bytes = Vec::with_capacity(size as usize); + io::default_read_to_end(&mut file, &mut bytes)?; Ok(bytes) } inner(path.as_ref()) @@ -288,8 +289,9 @@ pub fn read<P: AsRef<Path>>(path: P) -> io::Result<Vec<u8>> { pub fn read_to_string<P: AsRef<Path>>(path: P) -> io::Result<String> { fn inner(path: &Path) -> io::Result<String> { let mut file = File::open(path)?; - let mut string = String::new(); - file.read_to_string(&mut string)?; + let size = file.metadata().map(|m| m.len()).unwrap_or(0); + let mut string = String::with_capacity(size as usize); + io::default_read_to_string(&mut file, &mut string)?; Ok(string) } inner(path.as_ref()) @@ -1510,7 +1512,7 @@ impl FileType { } /// Tests whether this file type represents a regular file. - /// The result is mutually exclusive to the results of + /// The result is mutually exclusive to the results of /// [`is_dir`] and [`is_symlink`]; only zero or one of these /// tests may pass. /// |