diff --git a/clippy_lints/src/write.rs b/clippy_lints/src/write.rs index e653240d0491..fac63bcb9937 100644 --- a/clippy_lints/src/write.rs +++ b/clippy_lints/src/write.rs @@ -322,11 +322,15 @@ impl EarlyLintPass for Write { } /// Given a format string that ends in a newline and its span, calculates the span of the -/// newline. +/// newline, or the format string itself if the format string consists solely of a newline. fn newline_span(fmtstr: &StrLit) -> Span { let sp = fmtstr.span; let contents = &fmtstr.symbol.as_str(); + if *contents == r"\n" { + return sp; + } + let newline_sp_hi = sp.hi() - match fmtstr.style { StrStyle::Cooked => BytePos(1), diff --git a/tests/ui/print_with_newline.rs b/tests/ui/print_with_newline.rs index 3f710540e903..a43a1fc4f524 100644 --- a/tests/ui/print_with_newline.rs +++ b/tests/ui/print_with_newline.rs @@ -9,6 +9,7 @@ fn main() { print!("Hello {}\n", "world"); print!("Hello {} {}\n", "world", "#2"); print!("{}\n", 1265); + print!("\n"); // these are all fine print!(""); diff --git a/tests/ui/print_with_newline.stderr b/tests/ui/print_with_newline.stderr index 05fe88915d6e..54b3ad75b31e 100644 --- a/tests/ui/print_with_newline.stderr +++ b/tests/ui/print_with_newline.stderr @@ -44,7 +44,18 @@ LL | println!("{}", 1265); | ^^^^^^^ -- error: using `print!()` with a format string that ends in a single newline - --> $DIR/print_with_newline.rs:30:5 + --> $DIR/print_with_newline.rs:12:5 + | +LL | print!("/n"); + | ^^^^^^^^^^^^ + | +help: use `println!` instead + | +LL | println!(); + | ^^^^^^^ -- + +error: using `print!()` with a format string that ends in a single newline + --> $DIR/print_with_newline.rs:31:5 | LL | print!("//n"); // should fail | ^^^^^^^^^^^^^^ @@ -55,7 +66,7 @@ LL | println!("/"); // should fail | ^^^^^^^ -- error: using `print!()` with a format string that ends in a single newline - --> $DIR/print_with_newline.rs:37:5 + --> $DIR/print_with_newline.rs:38:5 | LL | / print!( LL | | " @@ -70,7 +81,7 @@ LL | "" | error: using `print!()` with a format string that ends in a single newline - --> $DIR/print_with_newline.rs:41:5 + --> $DIR/print_with_newline.rs:42:5 | LL | / print!( LL | | r" @@ -85,7 +96,7 @@ LL | r"" | error: using `print!()` with a format string that ends in a single newline - --> $DIR/print_with_newline.rs:49:5 + --> $DIR/print_with_newline.rs:50:5 | LL | print!("/r/n"); //~ ERROR | ^^^^^^^^^^^^^^^ @@ -96,7 +107,7 @@ LL | println!("/r"); //~ ERROR | ^^^^^^^ -- error: using `print!()` with a format string that ends in a single newline - --> $DIR/print_with_newline.rs:50:5 + --> $DIR/print_with_newline.rs:51:5 | LL | print!("foo/rbar/n") // ~ ERROR | ^^^^^^^^^^^^^^^^^^^^ @@ -106,5 +117,5 @@ help: use `println!` instead LL | println!("foo/rbar") // ~ ERROR | ^^^^^^^ -- -error: aborting due to 9 previous errors +error: aborting due to 10 previous errors diff --git a/tests/ui/write_with_newline.rs b/tests/ui/write_with_newline.rs index 93afd73d1114..1c1b1b58402e 100644 --- a/tests/ui/write_with_newline.rs +++ b/tests/ui/write_with_newline.rs @@ -14,6 +14,7 @@ fn main() { write!(&mut v, "Hello {}\n", "world"); write!(&mut v, "Hello {} {}\n", "world", "#2"); write!(&mut v, "{}\n", 1265); + write!(&mut v, "\n"); // These should be fine write!(&mut v, ""); diff --git a/tests/ui/write_with_newline.stderr b/tests/ui/write_with_newline.stderr index 2473329ca727..a14e86122ee5 100644 --- a/tests/ui/write_with_newline.stderr +++ b/tests/ui/write_with_newline.stderr @@ -44,7 +44,18 @@ LL | writeln!(&mut v, "{}", 1265); | ^^^^^^^ -- error: using `write!()` with a format string that ends in a single newline - --> $DIR/write_with_newline.rs:35:5 + --> $DIR/write_with_newline.rs:17:5 + | +LL | write!(&mut v, "/n"); + | ^^^^^^^^^^^^^^^^^^^^ + | +help: use `writeln!()` instead + | +LL | writeln!(&mut v, ); + | ^^^^^^^ -- + +error: using `write!()` with a format string that ends in a single newline + --> $DIR/write_with_newline.rs:36:5 | LL | write!(&mut v, "//n"); // should fail | ^^^^^^^^^^^^^^^^^^^^^^ @@ -55,7 +66,7 @@ LL | writeln!(&mut v, "/"); // should fail | ^^^^^^^ -- error: using `write!()` with a format string that ends in a single newline - --> $DIR/write_with_newline.rs:42:5 + --> $DIR/write_with_newline.rs:43:5 | LL | / write!( LL | | &mut v, @@ -72,7 +83,7 @@ LL | "" | error: using `write!()` with a format string that ends in a single newline - --> $DIR/write_with_newline.rs:47:5 + --> $DIR/write_with_newline.rs:48:5 | LL | / write!( LL | | &mut v, @@ -89,7 +100,7 @@ LL | r"" | error: using `write!()` with a format string that ends in a single newline - --> $DIR/write_with_newline.rs:56:5 + --> $DIR/write_with_newline.rs:57:5 | LL | write!(&mut v, "/r/n"); //~ ERROR | ^^^^^^^^^^^^^^^^^^^^^^^ @@ -100,7 +111,7 @@ LL | writeln!(&mut v, "/r"); //~ ERROR | ^^^^^^^ -- error: using `write!()` with a format string that ends in a single newline - --> $DIR/write_with_newline.rs:57:5 + --> $DIR/write_with_newline.rs:58:5 | LL | write!(&mut v, "foo/rbar/n"); | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ @@ -110,5 +121,5 @@ help: use `writeln!()` instead LL | writeln!(&mut v, "foo/rbar"); | ^^^^^^^ -- -error: aborting due to 9 previous errors +error: aborting due to 10 previous errors