rust/tests/ui/write_literal.rs

56 lines
2.0 KiB
Rust
Raw Normal View History

2018-10-06 18:18:06 +02:00
// Copyright 2014-2018 The Rust Project Developers. See the COPYRIGHT
// file at the top-level directory of this distribution.
//
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
// option. This file may not be copied, modified, or distributed
// except according to those terms.
2018-10-11 12:16:22 +02:00
2018-07-28 17:34:52 +02:00
#![allow(unused_must_use)]
2018-07-28 17:34:52 +02:00
#![warn(clippy::write_literal)]
use std::io::Write;
fn main() {
let mut v = Vec::new();
// these should be fine
write!(&mut v, "Hello");
writeln!(&mut v, "Hello");
let world = "world";
writeln!(&mut v, "Hello {}", world);
2018-07-26 00:14:11 +02:00
writeln!(&mut v, "Hello {world}", world=world);
writeln!(&mut v, "3 in hex is {:X}", 3);
writeln!(&mut v, "2 + 1 = {:.4}", 3);
writeln!(&mut v, "2 + 1 = {:5.4}", 3);
writeln!(&mut v, "Debug test {:?}", "hello, world");
writeln!(&mut v, "{0:8} {1:>8}", "hello", "world");
writeln!(&mut v, "{1:8} {0:>8}", "hello", "world");
writeln!(&mut v, "{foo:8} {bar:>8}", foo="hello", bar="world");
writeln!(&mut v, "{bar:8} {foo:>8}", foo="hello", bar="world");
writeln!(&mut v, "{number:>width$}", number=1, width=6);
writeln!(&mut v, "{number:>0width$}", number=1, width=6);
// these should throw warnings
writeln!(&mut v, "{} of {:b} people know binary, the other half doesn't", 1, 2);
write!(&mut v, "Hello {}", "world");
writeln!(&mut v, "Hello {} {}", world, "world");
writeln!(&mut v, "Hello {}", "world");
writeln!(&mut v, "10 / 4 is {}", 2.5);
writeln!(&mut v, "2 + 1 = {}", 3);
// positional args don't change the fact
// that we're using a literal -- this should
// throw a warning
writeln!(&mut v, "{0} {1}", "hello", "world");
writeln!(&mut v, "{1} {0}", "hello", "world");
// named args shouldn't change anything either
writeln!(&mut v, "{foo} {bar}", foo="hello", bar="world");
writeln!(&mut v, "{bar} {foo}", foo="hello", bar="world");
}