Downgrade match_wild_err_arm to pedantic and update help messages

clippy_lints/src/lib.rs

@@ -1141,6 +1141,7 @@ pub fn register_plugins(store: &mut rustc_lint::LintStore, sess: &Session, conf:
  LintId::of(&match_on_vec_items::MATCH_ON_VEC_ITEMS),
  LintId::of(&matches::MATCH_BOOL),
  LintId::of(&matches::MATCH_WILDCARD_FOR_SINGLE_VARIANTS),
+ LintId::of(&matches::MATCH_WILD_ERR_ARM),
  LintId::of(&matches::SINGLE_MATCH_ELSE),
  LintId::of(&methods::FILTER_MAP),
  LintId::of(&methods::FILTER_MAP_NEXT),
@@ -1285,7 +1286,6 @@ pub fn register_plugins(store: &mut rustc_lint::LintStore, sess: &Session, conf:
  LintId::of(&matches::MATCH_OVERLAPPING_ARM),
  LintId::of(&matches::MATCH_REF_PATS),
  LintId::of(&matches::MATCH_SINGLE_BINDING),
- LintId::of(&matches::MATCH_WILD_ERR_ARM),
  LintId::of(&matches::SINGLE_MATCH),
  LintId::of(&matches::WILDCARD_IN_OR_PATTERNS),
  LintId::of(&mem_discriminant::MEM_DISCRIMINANT_NON_ENUM),
@@ -1476,7 +1476,6 @@ pub fn register_plugins(store: &mut rustc_lint::LintStore, sess: &Session, conf:
  LintId::of(&matches::INFALLIBLE_DESTRUCTURING_MATCH),
  LintId::of(&matches::MATCH_OVERLAPPING_ARM),
  LintId::of(&matches::MATCH_REF_PATS),
- LintId::of(&matches::MATCH_WILD_ERR_ARM),
  LintId::of(&matches::SINGLE_MATCH),
  LintId::of(&mem_replace::MEM_REPLACE_OPTION_WITH_NONE),
  LintId::of(&mem_replace::MEM_REPLACE_WITH_DEFAULT),

clippy_lints/src/matches.rs

@@ -168,7 +168,7 @@ declare_clippy_lint! {
  /// **What it does:** Checks for arm which matches all errors with `Err(_)`
  /// and take drastic actions like `panic!`.
  ///
- /// **Why is this bad?** It is generally a bad practice, just like
+ /// **Why is this bad?** It is generally a bad practice, similar to
  /// catching all exceptions in java with `catch(Exception)`
  ///
  /// **Known problems:** None.
@@ -182,7 +182,7 @@ declare_clippy_lint! {
  /// }
  /// ```
  pub MATCH_WILD_ERR_ARM,
- style,
+ pedantic,
  "a `match` with `Err(_)` arm and take drastic actions"
 }
 
@@ -711,7 +711,7 @@ fn check_wild_err_arm(cx: &LateContext<'_, '_>, ex: &Expr<'_>, arms: &[Arm<'_>])
  arm.pat.span,
  &format!("`Err({})` matches all errors", &ident_bind_name),
  None,
- "match each error separately or use the error output",
+ "match each error separately or use the error output, or use `.except(msg)` if the error case is unreachable",
  );
  }
  }

src/lintlist/mod.rs

@@ -1195,7 +1195,7 @@ pub static ref ALL_LINTS: Vec<Lint> = vec![
  },
  Lint {
  name: "match_wild_err_arm",
- group: "style",
+ group: "pedantic",
  desc: "a `match` with `Err(_)` arm and take drastic actions",
  deprecation: None,
  module: "matches",

tests/ui/future_not_send.stderr

@@ -47,17 +47,32 @@ error: future cannot be sent between threads safely
  --> $DIR/future_not_send.rs:20:63
  |
 LL | async fn private_future2(rc: Rc<[u8]>, cell: &Cell<usize>) -> bool {
- | ^^^^
+ | ^^^^ future returned by `private_future2` is not `Send`
  |
+note: captured value is not `Send`
+ --> $DIR/future_not_send.rs:20:26
+ |
+LL | async fn private_future2(rc: Rc<[u8]>, cell: &Cell<usize>) -> bool {
+ | ^^ has type `std::rc::Rc<[u8]>` which is not `Send`
  = note: `std::rc::Rc<[u8]>` doesn't implement `std::marker::Send`
+note: captured value is not `Send`
+ --> $DIR/future_not_send.rs:20:40
+ |
+LL | async fn private_future2(rc: Rc<[u8]>, cell: &Cell<usize>) -> bool {
+ | ^^^^ has type `&std::cell::Cell<usize>` which is not `Send`
  = note: `std::cell::Cell<usize>` doesn't implement `std::marker::Sync`
 
 error: future cannot be sent between threads safely
  --> $DIR/future_not_send.rs:24:43
  |
 LL | pub async fn public_future2(rc: Rc<[u8]>) {}
- | ^
+ | ^ future returned by `public_future2` is not `Send`
  |
+note: captured value is not `Send`
+ --> $DIR/future_not_send.rs:24:29
+ |
+LL | pub async fn public_future2(rc: Rc<[u8]>) {}
+ | ^^ has type `std::rc::Rc<[u8]>` which is not `Send`
  = note: `std::rc::Rc<[u8]>` doesn't implement `std::marker::Send`
 
 error: future cannot be sent between threads safely
@@ -117,8 +132,13 @@ error: future cannot be sent between threads safely
  --> $DIR/future_not_send.rs:66:34
  |
 LL | async fn unclear_future<T>(t: T) {}
- | ^
+ | ^ future returned by `unclear_future` is not `Send`
  |
+note: captured value is not `Send`
+ --> $DIR/future_not_send.rs:66:28
+ |
+LL | async fn unclear_future<T>(t: T) {}
+ | ^ has type `T` which is not `Send`
  = note: `T` doesn't implement `std::marker::Send`
 
 error: aborting due to 8 previous errors

tests/ui/match_wild_err_arm.stderr

@@ -5,31 +5,31 @@ LL | Err(_) => panic!("err"),
  | ^^^^^^
  |
  = note: `-D clippy::match-wild-err-arm` implied by `-D warnings`
- = note: match each error separately or use the error output
+ = note: match each error separately or use the error output, or use `.except(msg)` if the error case is unreachable
 
 error: `Err(_)` matches all errors
  --> $DIR/match_wild_err_arm.rs:17:9
  |
 LL | Err(_) => panic!(),
  | ^^^^^^
  |
- = note: match each error separately or use the error output
+ = note: match each error separately or use the error output, or use `.except(msg)` if the error case is unreachable
 
 error: `Err(_)` matches all errors
  --> $DIR/match_wild_err_arm.rs:23:9
  |
 LL | Err(_) => {
  | ^^^^^^
  |
- = note: match each error separately or use the error output
+ = note: match each error separately or use the error output, or use `.except(msg)` if the error case is unreachable
 
 error: `Err(_e)` matches all errors
  --> $DIR/match_wild_err_arm.rs:31:9
  |
 LL | Err(_e) => panic!(),
  | ^^^^^^^
  |
- = note: match each error separately or use the error output
+ = note: match each error separately or use the error output, or use `.except(msg)` if the error case is unreachable
 
 error: aborting due to 4 previous errors