src/tools/clippy/tests/ui/write_with_newline.rs

   1 // FIXME: Ideally these suggestions would be fixed via rustfix. Blocked by rust-lang/rust#53934
   2 // // run-rustfix
   3
   4 #![allow(clippy::write_literal)]
   5 #![warn(clippy::write_with_newline)]
   6
   7 use std::io::Write;
   8
   9 fn main() {
  10     let mut v = Vec::new();
  11
  12     // These should fail
  13     write!(v, "Hello\n");
  14     write!(v, "Hello {}\n", "world");
  15     write!(v, "Hello {} {}\n", "world", "#2");
  16     write!(v, "{}\n", 1265);
  17     write!(v, "\n");
  18
  19     // These should be fine
  20     write!(v, "");
  21     write!(v, "Hello");
  22     writeln!(v, "Hello");
  23     writeln!(v, "Hello\n");
  24     writeln!(v, "Hello {}\n", "world");
  25     write!(v, "Issue\n{}", 1265);
  26     write!(v, "{}", 1265);
  27     write!(v, "\n{}", 1275);
  28     write!(v, "\n\n");
  29     write!(v, "like eof\n\n");
  30     write!(v, "Hello {} {}\n\n", "world", "#2");
  31     writeln!(v, "\ndon't\nwarn\nfor\nmultiple\nnewlines\n"); // #3126
  32     writeln!(v, "\nbla\n\n"); // #3126
  33
  34     // Escaping
  35     write!(v, "\\n"); // #3514
  36     write!(v, "\\\n"); // should fail
  37     write!(v, "\\\\n");
  38
  39     // Raw strings
  40     write!(v, r"\n"); // #3778
  41
  42     // Literal newlines should also fail
  43     write!(
  44         v,
  45         "
  46 "
  47     );
  48     write!(
  49         v,
  50         r"
  51 "
  52     );
  53
  54     // Don't warn on CRLF (#4208)
  55     write!(v, "\r\n");
  56     write!(v, "foo\r\n");
  57     write!(v, "\\r\n"); //~ ERROR
  58     write!(v, "foo\rbar\n");
  59 }