diff options
| -rw-r--r-- | clippy_lints/src/loops/manual_flatten.rs | 16 | ||||
| -rw-r--r-- | tests/lint_message_convention.rs | 1 | ||||
| -rw-r--r-- | tests/ui/manual_flatten.rs | 16 | ||||
| -rw-r--r-- | tests/ui/manual_flatten.stderr | 30 |
4 files changed, 59 insertions, 4 deletions
diff --git a/clippy_lints/src/loops/manual_flatten.rs b/clippy_lints/src/loops/manual_flatten.rs index d276c901059..1d6ddf4b99f 100644 --- a/clippy_lints/src/loops/manual_flatten.rs +++ b/clippy_lints/src/loops/manual_flatten.rs @@ -51,22 +51,32 @@ pub(super) fn check<'tcx>( _ => "" }; + let sugg = format!("{arg_snippet}{copied}.flatten()"); + + // If suggestion is not a one-liner, it won't be shown inline within the error message. In that case, + // it will be shown in the extra `help` message at the end, which is why the first `help_msg` needs + // to refer to the correct relative position of the suggestion. + let help_msg = if sugg.contains('\n') { + "remove the `if let` statement in the for loop and then..." + } else { + "...and remove the `if let` statement in the for loop" + }; + span_lint_and_then( cx, MANUAL_FLATTEN, span, &msg, |diag| { - let sugg = format!("{}{}.flatten()", arg_snippet, copied); diag.span_suggestion( arg.span, "try", sugg, - Applicability::MaybeIncorrect, + applicability, ); diag.span_help( inner_expr.span, - "...and remove the `if let` statement in the for loop", + help_msg, ); } ); diff --git a/tests/lint_message_convention.rs b/tests/lint_message_convention.rs index dd1d4412036..9519c2e9379 100644 --- a/tests/lint_message_convention.rs +++ b/tests/lint_message_convention.rs @@ -42,6 +42,7 @@ impl Message { r".*remove .*the return type...", r"note: Clippy version: .*", r"the compiler unexpectedly panicked. this is a bug.", + r"remove the `if let` statement in the for loop and then...", ]) .unwrap(); diff --git a/tests/ui/manual_flatten.rs b/tests/ui/manual_flatten.rs index 6c5232ec5f5..d922593bc6f 100644 --- a/tests/ui/manual_flatten.rs +++ b/tests/ui/manual_flatten.rs @@ -106,4 +106,20 @@ fn main() { for n in vec![Some(1), Some(2), Some(3)].iter().flatten() { println!("{}", n); } + + run_unformatted_tests(); +} + +#[rustfmt::skip] +fn run_unformatted_tests() { + // Skip rustfmt here on purpose so the suggestion does not fit in one line + for n in vec![ + Some(1), + Some(2), + Some(3) + ].iter() { + if let Some(n) = n { + println!("{:?}", n); + } + } } diff --git a/tests/ui/manual_flatten.stderr b/tests/ui/manual_flatten.stderr index 392e1a39393..da053c05668 100644 --- a/tests/ui/manual_flatten.stderr +++ b/tests/ui/manual_flatten.stderr @@ -167,5 +167,33 @@ LL | | println!("{:?}", n); LL | | } | |_________^ -error: aborting due to 8 previous errors +error: unnecessary `if let` since only the `Some` variant of the iterator element is used + --> $DIR/manual_flatten.rs:116:5 + | +LL | / for n in vec![ +LL | | Some(1), +LL | | Some(2), +LL | | Some(3) +... | +LL | | } +LL | | } + | |_____^ + | +help: remove the `if let` statement in the for loop and then... + --> $DIR/manual_flatten.rs:121:9 + | +LL | / if let Some(n) = n { +LL | | println!("{:?}", n); +LL | | } + | |_________^ +help: try + | +LL ~ for n in vec![ +LL + Some(1), +LL + Some(2), +LL + Some(3) +LL ~ ].iter().flatten() { + | + +error: aborting due to 9 previous errors |