rust-clippy/tests/ui/uninlined_format_args.rs
Yuri Astrakhan 5a71bbdf3f new uninlined_format_args lint to inline explicit arguments
Implement https://github.com/rust-lang/rust-clippy/issues/8368 - a new
lint to inline format arguments such as `print!("{}", var)` into
`print!("{var}")`.

code | suggestion | comment
---|---|---
`print!("{}", var)` | `print!("{var}")` |  simple variables
`print!("{0}", var)` | `print!("{var}")` |  positional variables
`print!("{v}", v=var)` | `print!("{var}")` |  named variables
`print!("{0} {0}", var)` | `print!("{var} {var}")` |  aliased variables
`print!("{0:1$}", var, width)` | `print!("{var:width$}")` |  width
support
`print!("{0:.1$}", var, prec)` | `print!("{var:.prec$}")` |  precision
support
`print!("{:.*}", prec, var)` | `print!("{var:.prec$}")` |  asterisk
support

code | suggestion | comment
---|---|---
`print!("{0}={1}", var, 1+2)` | `print!("{var}={0}", 1+2)` | Format
string uses an indexed argument that cannot be inlined.  Supporting this
case requires re-indexing of the format string.

changelog: [`uninlined_format_args`]: A new lint to inline format
arguments, i.e. `print!("{}", var)` into `print!("{var}")`
2022-09-25 19:53:03 -04:00

171 lines
5.1 KiB
Rust

// run-rustfix
#![allow(clippy::eq_op)]
#![allow(clippy::format_in_format_args)]
#![allow(clippy::print_literal)]
#![allow(named_arguments_used_positionally)]
#![allow(unused_variables, unused_imports, unused_macros)]
#![warn(clippy::uninlined_format_args)]
#![feature(custom_inner_attributes)]
macro_rules! no_param_str {
() => {
"{}"
};
}
macro_rules! pass_through {
($expr:expr) => {
$expr
};
}
macro_rules! my_println {
($($args:tt),*) => {{
println!($($args),*)
}};
}
macro_rules! my_println_args {
($($args:tt),*) => {{
println!("foo: {}", format_args!($($args),*))
}};
}
fn tester(fn_arg: i32) {
let local_i32 = 1;
let local_f64 = 2.0;
let local_opt: Option<i32> = Some(3);
let width = 4;
let prec = 5;
let val = 6;
// make sure this file hasn't been corrupted with tabs converted to spaces
// let _ = ' '; // <- this is a single tab character
let _: &[u8; 3] = b" "; // <- <tab><space><tab>
println!("val='{}'", local_i32);
println!("val='{ }'", local_i32); // 3 spaces
println!("val='{ }'", local_i32); // tab
println!("val='{ }'", local_i32); // space+tab
println!("val='{ }'", local_i32); // tab+space
println!(
"val='{
}'",
local_i32
);
println!("{}", local_i32);
println!("{}", fn_arg);
println!("{:?}", local_i32);
println!("{:#?}", local_i32);
println!("{:4}", local_i32);
println!("{:04}", local_i32);
println!("{:<3}", local_i32);
println!("{:#010x}", local_i32);
println!("{:.1}", local_f64);
println!("Hello {} is {:.*}", "x", local_i32, local_f64);
println!("Hello {} is {:.*}", local_i32, 5, local_f64);
println!("Hello {} is {2:.*}", local_i32, 5, local_f64);
println!("{} {}", local_i32, local_f64);
println!("{}, {}", local_i32, local_opt.unwrap());
println!("{}", val);
println!("{}", v = val);
println!("{} {1}", local_i32, 42);
println!("val='{\t }'", local_i32);
println!("val='{\n }'", local_i32);
println!("val='{local_i32}'", local_i32 = local_i32);
println!("val='{local_i32}'", local_i32 = fn_arg);
println!("{0}", local_i32);
println!("{0:?}", local_i32);
println!("{0:#?}", local_i32);
println!("{0:04}", local_i32);
println!("{0:<3}", local_i32);
println!("{0:#010x}", local_i32);
println!("{0:.1}", local_f64);
println!("{0} {0}", local_i32);
println!("{1} {} {0} {}", local_i32, local_f64);
println!("{0} {1}", local_i32, local_f64);
println!("{1} {0}", local_i32, local_f64);
println!("{1} {0} {1} {0}", local_i32, local_f64);
println!("{1} {0}", "str", local_i32);
println!("{v}", v = local_i32);
println!("{local_i32:0$}", width);
println!("{local_i32:w$}", w = width);
println!("{local_i32:.0$}", prec);
println!("{local_i32:.p$}", p = prec);
println!("{:0$}", v = val);
println!("{0:0$}", v = val);
println!("{:0$.0$}", v = val);
println!("{0:0$.0$}", v = val);
println!("{0:0$.v$}", v = val);
println!("{0:v$.0$}", v = val);
println!("{v:0$.0$}", v = val);
println!("{v:v$.0$}", v = val);
println!("{v:0$.v$}", v = val);
println!("{v:v$.v$}", v = val);
println!("{:0$}", width);
println!("{:1$}", local_i32, width);
println!("{:w$}", w = width);
println!("{:w$}", local_i32, w = width);
println!("{:.0$}", prec);
println!("{:.1$}", local_i32, prec);
println!("{:.p$}", p = prec);
println!("{:.p$}", local_i32, p = prec);
println!("{:0$.1$}", width, prec);
println!("{:0$.w$}", width, w = prec);
println!("{:1$.2$}", local_f64, width, prec);
println!("{:1$.2$} {0} {1} {2}", local_f64, width, prec);
println!(
"{0:1$.2$} {0:2$.1$} {1:0$.2$} {1:2$.0$} {2:0$.1$} {2:1$.0$}",
local_i32, width, prec,
);
println!(
"{0:1$.2$} {0:2$.1$} {1:0$.2$} {1:2$.0$} {2:0$.1$} {2:1$.0$} {3}",
local_i32,
width,
prec,
1 + 2
);
println!("Width = {}, value with width = {:0$}", local_i32, local_f64);
println!("{:w$.p$}", local_i32, w = width, p = prec);
println!("{:w$.p$}", w = width, p = prec);
println!("{}", format!("{}", local_i32));
my_println!("{}", local_i32);
my_println_args!("{}", local_i32);
// these should NOT be modified by the lint
println!(concat!("nope ", "{}"), local_i32);
println!("val='{local_i32}'");
println!("val='{local_i32 }'");
println!("val='{local_i32 }'"); // with tab
println!("val='{local_i32\n}'");
println!("{}", usize::MAX);
println!("{}", local_opt.unwrap());
println!(
"val='{local_i32
}'"
);
println!(no_param_str!(), local_i32);
// FIXME: bugs!
// println!(pass_through!("foo={local_i32}"), local_i32 = local_i32);
// println!(pass_through!("foo={}"), local_i32);
// println!(indoc!("foo={}"), local_i32);
// printdoc!("foo={}", local_i32);
}
fn main() {
tester(42);
}
fn _under_msrv() {
#![clippy::msrv = "1.57"]
let local_i32 = 1;
println!("don't expand='{}'", local_i32);
}
fn _meets_msrv() {
#![clippy::msrv = "1.58"]
let local_i32 = 1;
println!("expand='{}'", local_i32);
}