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// run-rustfix
#![allow(
unused_tuple_struct_fields,
clippy::print_literal,
clippy::redundant_clone,
clippy::to_string_in_format_args,
clippy::needless_borrow
)]
#![warn(clippy::useless_format)]
struct Foo(pub String);
macro_rules! foo {
($($t:tt)*) => (Foo(format!($($t)*)))
}
fn main() {
"foo".to_string();
"{}".to_string();
"{} abc {}".to_string();
r##"foo {}
" bar"##.to_string();
let _ = String::new();
"foo".to_string();
format!("{:?}", "foo"); // Don't warn about `Debug`.
format!("{:8}", "foo");
format!("{:width$}", "foo", width = 8);
"foo".to_string(); // Warn when the format makes no difference.
"foo".to_string(); // Warn when the format makes no difference.
format!("foo {}", "bar");
format!("{} bar", "foo");
let arg: String = "".to_owned();
arg.to_string();
format!("{:?}", arg); // Don't warn about debug.
format!("{:8}", arg);
format!("{:width$}", arg, width = 8);
arg.to_string(); // Warn when the format makes no difference.
arg.to_string(); // Warn when the format makes no difference.
format!("foo {}", arg);
format!("{} bar", arg);
// We don’t want to warn for non-string args; see issue #697.
format!("{}", 42);
format!("{:?}", 42);
format!("{:+}", 42);
format!("foo {}", 42);
format!("{} bar", 42);
// We only want to warn about `format!` itself.
println!("foo");
println!("{}", "foo");
println!("foo {}", "foo");
println!("{}", 42);
println!("foo {}", 42);
// A `format!` inside a macro should not trigger a warning.
foo!("should not warn");
// Precision on string means slicing without panicking on size.
format!("{:.1}", "foo"); // Could be `"foo"[..1]`
format!("{:.10}", "foo"); // Could not be `"foo"[..10]`
format!("{:.prec$}", "foo", prec = 1);
format!("{:.prec$}", "foo", prec = 10);
42.to_string();
let x = std::path::PathBuf::from("/bar/foo/qux");
x.display().to_string();
// False positive
let a = "foo".to_string();
let _ = Some(a + "bar");
// Wrap it with braces
let v: Vec<String> = vec!["foo".to_string(), "bar".to_string()];
let _s: String = (&*v.join("\n")).to_string();
format!("prepend {:+}", "s");
// Issue #8290
let x = "foo";
let _ = x.to_string();
let _ = format!("{x:?}"); // Don't lint on debug
let _ = x.to_string();
// Issue #9234
let abc = "abc";
let _ = abc.to_string();
let xx = "xx";
let _ = xx.to_string();
}
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