From 17d40c6057c88f4c432b0d7bac88e1b84cb7e67f Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Wed, 17 Apr 2024 14:03:36 +0200 Subject: Adding upstream version 1.65.0+dfsg1. Signed-off-by: Daniel Baumann --- src/tools/clippy/src/docs/read_zero_byte_vec.txt | 30 ++++++++++++++++++++++++ 1 file changed, 30 insertions(+) create mode 100644 src/tools/clippy/src/docs/read_zero_byte_vec.txt (limited to 'src/tools/clippy/src/docs/read_zero_byte_vec.txt') diff --git a/src/tools/clippy/src/docs/read_zero_byte_vec.txt b/src/tools/clippy/src/docs/read_zero_byte_vec.txt new file mode 100644 index 000000000..cef5604e0 --- /dev/null +++ b/src/tools/clippy/src/docs/read_zero_byte_vec.txt @@ -0,0 +1,30 @@ +### What it does +This lint catches reads into a zero-length `Vec`. +Especially in the case of a call to `with_capacity`, this lint warns that read +gets the number of bytes from the `Vec`'s length, not its capacity. + +### Why is this bad? +Reading zero bytes is almost certainly not the intended behavior. + +### Known problems +In theory, a very unusual read implementation could assign some semantic meaning +to zero-byte reads. But it seems exceptionally unlikely that code intending to do +a zero-byte read would allocate a `Vec` for it. + +### Example +``` +use std::io; +fn foo(mut f: F) { + let mut data = Vec::with_capacity(100); + f.read(&mut data).unwrap(); +} +``` +Use instead: +``` +use std::io; +fn foo(mut f: F) { + let mut data = Vec::with_capacity(100); + data.resize(100, 0); + f.read(&mut data).unwrap(); +} +``` \ No newline at end of file -- cgit v1.2.3