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// run-rustfix
#![allow(clippy::print_literal, clippy::redundant_clone)]
#![warn(clippy::useless_format)]
struct Foo(pub String);
macro_rules! foo {
($($t:tt)*) => (Foo(format!($($t)*)))
}
fn main() {
format!("foo");
format!("{{}}");
format!("{{}} abc {{}}");
format!(
r##"foo {{}}
" bar"##
);
format!("{}", "foo");
format!("{:?}", "foo"); // Don't warn about `Debug`.
format!("{:8}", "foo");
format!("{:width$}", "foo", width = 8);
format!("{:+}", "foo"); // Warn when the format makes no difference.
format!("{:<}", "foo"); // Warn when the format makes no difference.
format!("foo {}", "bar");
format!("{} bar", "foo");
let arg: String = "".to_owned();
format!("{}", arg);
format!("{:?}", arg); // Don't warn about debug.
format!("{:8}", arg);
format!("{:width$}", arg, width = 8);
format!("{:+}", arg); // Warn when the format makes no difference.
format!("{:<}", arg); // 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);
format!("{}", 42.to_string());
let x = std::path::PathBuf::from("/bar/foo/qux");
format!("{}", x.display().to_string());
// False positive
let a = "foo".to_string();
let _ = Some(format!("{}", a + "bar"));
}
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