diff --git a/compiler/rustc_ast/src/util/parser.rs b/compiler/rustc_ast/src/util/parser.rs index 1d4b01aa94c9d..8f2b7a23c01c8 100644 --- a/compiler/rustc_ast/src/util/parser.rs +++ b/compiler/rustc_ast/src/util/parser.rs @@ -153,9 +153,10 @@ impl AssocOp { match *self { Assign | AssignOp(_) => Fixity::Right, As | Multiply | Divide | Modulus | Add | Subtract | ShiftLeft | ShiftRight | BitAnd - | BitXor | BitOr | Less | Greater | LessEqual | GreaterEqual | Equal | NotEqual - | LAnd | LOr => Fixity::Left, - DotDot | DotDotEq => Fixity::None, + | BitXor | BitOr | LAnd | LOr => Fixity::Left, + Less | Greater | LessEqual | GreaterEqual | Equal | NotEqual | DotDot | DotDotEq => { + Fixity::None + } } } diff --git a/compiler/rustc_mir_build/src/builder/scope.rs b/compiler/rustc_mir_build/src/builder/scope.rs index fd9f9da6e770c..35c98037827af 100644 --- a/compiler/rustc_mir_build/src/builder/scope.rs +++ b/compiler/rustc_mir_build/src/builder/scope.rs @@ -1481,14 +1481,6 @@ fn build_scope_drops<'tcx>( block = next; } DropKind::ForLint => { - // If the operand has been moved, and we are not on an unwind - // path, then don't generate the drop. (We only take this into - // account for non-unwind paths so as not to disturb the - // caching mechanism.) - if scope.moved_locals.iter().any(|&o| o == local) { - continue; - } - // As in the `DropKind::Storage` case below: // normally lint-related drops are not emitted for unwind, // so we can just leave `unwind_to` unmodified, but in some @@ -1500,6 +1492,14 @@ fn build_scope_drops<'tcx>( unwind_to = unwind_drops.drops[unwind_to].next; } + // If the operand has been moved, and we are not on an unwind + // path, then don't generate the drop. (We only take this into + // account for non-unwind paths so as not to disturb the + // caching mechanism.) + if scope.moved_locals.iter().any(|&o| o == local) { + continue; + } + cfg.push(block, Statement { source_info, kind: StatementKind::BackwardIncompatibleDropHint { @@ -1552,7 +1552,7 @@ impl<'a, 'tcx: 'a> Builder<'a, 'tcx> { let mut unwind_indices = IndexVec::from_elem_n(unwind_target, 1); for (drop_idx, drop_node) in drops.drops.iter_enumerated().skip(1) { match drop_node.data.kind { - DropKind::Storage => { + DropKind::Storage | DropKind::ForLint => { if is_coroutine { let unwind_drop = self .scopes @@ -1563,7 +1563,7 @@ impl<'a, 'tcx: 'a> Builder<'a, 'tcx> { unwind_indices.push(unwind_indices[drop_node.next]); } } - DropKind::Value | DropKind::ForLint => { + DropKind::Value => { let unwind_drop = self .scopes .unwind_drops diff --git a/compiler/rustc_parse/src/parser/expr.rs b/compiler/rustc_parse/src/parser/expr.rs index 2f4adf2af9e9d..7533e75ffe261 100644 --- a/compiler/rustc_parse/src/parser/expr.rs +++ b/compiler/rustc_parse/src/parser/expr.rs @@ -279,13 +279,9 @@ impl<'a> Parser<'a> { break; } - let fixity = op.fixity(); - let min_prec = match fixity { + let min_prec = match op.fixity() { Fixity::Right => Bound::Included(prec), - Fixity::Left => Bound::Excluded(prec), - // We currently have no non-associative operators that are not handled above by - // the special cases. The code is here only for future convenience. - Fixity::None => Bound::Excluded(prec), + Fixity::Left | Fixity::None => Bound::Excluded(prec), }; let (rhs, _) = self.with_res(restrictions - Restrictions::STMT_EXPR, |this| { let attrs = this.parse_outer_attributes()?; @@ -337,10 +333,6 @@ impl<'a> Parser<'a> { self.dcx().span_bug(span, "AssocOp should have been handled by special case") } }; - - if let Fixity::None = fixity { - break; - } } Ok((lhs, parsed_something)) diff --git a/compiler/rustc_parse/src/parser/stmt.rs b/compiler/rustc_parse/src/parser/stmt.rs index 151abf0be9508..1ddb5fc0a1169 100644 --- a/compiler/rustc_parse/src/parser/stmt.rs +++ b/compiler/rustc_parse/src/parser/stmt.rs @@ -745,6 +745,51 @@ impl<'a> Parser<'a> { Ok(self.mk_block(stmts, s, lo.to(self.prev_token.span))) } + fn recover_missing_dot(&mut self, err: &mut Diag<'_>) { + let Some((ident, _)) = self.token.ident() else { + return; + }; + if let Some(c) = ident.name.as_str().chars().next() + && c.is_uppercase() + { + return; + } + if self.token.is_reserved_ident() && !self.token.is_ident_named(kw::Await) { + return; + } + if self.prev_token.is_reserved_ident() && self.prev_token.is_ident_named(kw::Await) { + // Likely `foo.await bar` + } else if !self.prev_token.is_reserved_ident() && self.prev_token.is_ident() { + // Likely `foo bar` + } else if self.prev_token.kind == token::Question { + // `foo? bar` + } else if self.prev_token.kind == token::CloseDelim(Delimiter::Parenthesis) { + // `foo() bar` + } else { + return; + } + if self.token.span == self.prev_token.span { + // Account for syntax errors in proc-macros. + return; + } + if self.look_ahead(1, |t| [token::Semi, token::Question, token::Dot].contains(&t.kind)) { + err.span_suggestion_verbose( + self.prev_token.span.between(self.token.span), + "you might have meant to write a field access", + ".".to_string(), + Applicability::MaybeIncorrect, + ); + } + if self.look_ahead(1, |t| t.kind == token::OpenDelim(Delimiter::Parenthesis)) { + err.span_suggestion_verbose( + self.prev_token.span.between(self.token.span), + "you might have meant to write a method call", + ".".to_string(), + Applicability::MaybeIncorrect, + ); + } + } + /// Parses a statement, including the trailing semicolon. pub fn parse_full_stmt( &mut self, @@ -851,7 +896,8 @@ impl<'a> Parser<'a> { Some(if recover.no() { res? } else { - res.unwrap_or_else(|e| { + res.unwrap_or_else(|mut e| { + self.recover_missing_dot(&mut e); let guar = e.emit(); self.recover_stmt(); guar @@ -872,7 +918,12 @@ impl<'a> Parser<'a> { // We might be at the `,` in `let x = foo;`. Try to recover. match &mut local.kind { LocalKind::Init(expr) | LocalKind::InitElse(expr, _) => { - self.check_mistyped_turbofish_with_multiple_type_params(e, expr)?; + self.check_mistyped_turbofish_with_multiple_type_params(e, expr).map_err( + |mut e| { + self.recover_missing_dot(&mut e); + e + }, + )?; // We found `foo`, have we fully recovered? self.expect_semi()?; } diff --git a/library/alloc/src/collections/binary_heap/mod.rs b/library/alloc/src/collections/binary_heap/mod.rs index 116e0e73e9659..965fd63a52981 100644 --- a/library/alloc/src/collections/binary_heap/mod.rs +++ b/library/alloc/src/collections/binary_heap/mod.rs @@ -531,8 +531,7 @@ impl BinaryHeap { /// heap.push(1); /// heap.push(5); /// heap.push(2); - /// { - /// let mut val = heap.peek_mut().unwrap(); + /// if let Some(mut val) = heap.peek_mut() { /// *val = 0; /// } /// assert_eq!(heap.peek(), Some(&2)); diff --git a/library/core/src/cell/once.rs b/library/core/src/cell/once.rs index c14afe0f4761c..6a85791916a61 100644 --- a/library/core/src/cell/once.rs +++ b/library/core/src/cell/once.rs @@ -262,7 +262,9 @@ impl OnceCell { /// /// let value = cell.get_mut_or_try_init(|| "1234".parse()); /// assert_eq!(value, Ok(&mut 1234)); - /// *value.unwrap() += 2; + /// + /// let Ok(value) = value else { return; }; + /// *value += 2; /// assert_eq!(cell.get(), Some(&1236)) /// ``` #[unstable(feature = "once_cell_get_mut", issue = "121641")] @@ -304,8 +306,8 @@ impl OnceCell { /// assert_eq!(cell.into_inner(), None); /// /// let cell = OnceCell::new(); - /// cell.set("hello".to_string()).unwrap(); - /// assert_eq!(cell.into_inner(), Some("hello".to_string())); + /// let _ = cell.set("hello".to_owned()); + /// assert_eq!(cell.into_inner(), Some("hello".to_owned())); /// ``` #[inline] #[stable(feature = "once_cell", since = "1.70.0")] @@ -332,8 +334,8 @@ impl OnceCell { /// assert_eq!(cell.take(), None); /// /// let mut cell = OnceCell::new(); - /// cell.set("hello".to_string()).unwrap(); - /// assert_eq!(cell.take(), Some("hello".to_string())); + /// let _ = cell.set("hello".to_owned()); + /// assert_eq!(cell.take(), Some("hello".to_owned())); /// assert_eq!(cell.get(), None); /// ``` #[inline] diff --git a/library/core/src/fmt/mod.rs b/library/core/src/fmt/mod.rs index 14c7006510162..c2c78dd9c67eb 100644 --- a/library/core/src/fmt/mod.rs +++ b/library/core/src/fmt/mod.rs @@ -152,8 +152,9 @@ pub trait Write { /// } /// /// let mut buf = String::new(); - /// writer(&mut buf, "hola").unwrap(); + /// writer(&mut buf, "hola")?; /// assert_eq!(&buf, "hola"); + /// # std::fmt::Result::Ok(()) /// ``` #[stable(feature = "rust1", since = "1.0.0")] fn write_str(&mut self, s: &str) -> Result; @@ -179,9 +180,10 @@ pub trait Write { /// } /// /// let mut buf = String::new(); - /// writer(&mut buf, 'a').unwrap(); - /// writer(&mut buf, 'b').unwrap(); + /// writer(&mut buf, 'a')?; + /// writer(&mut buf, 'b')?; /// assert_eq!(&buf, "ab"); + /// # std::fmt::Result::Ok(()) /// ``` #[stable(feature = "fmt_write_char", since = "1.1.0")] fn write_char(&mut self, c: char) -> Result { @@ -208,8 +210,9 @@ pub trait Write { /// } /// /// let mut buf = String::new(); - /// writer(&mut buf, "world").unwrap(); + /// writer(&mut buf, "world")?; /// assert_eq!(&buf, "world"); + /// # std::fmt::Result::Ok(()) /// ``` #[stable(feature = "rust1", since = "1.0.0")] fn write_fmt(&mut self, args: Arguments<'_>) -> Result { diff --git a/library/core/src/iter/sources/once.rs b/library/core/src/iter/sources/once.rs index 21be4377da1ca..c4a9860bdd76c 100644 --- a/library/core/src/iter/sources/once.rs +++ b/library/core/src/iter/sources/once.rs @@ -34,7 +34,7 @@ use crate::iter::{FusedIterator, TrustedLen}; /// use std::fs; /// use std::path::PathBuf; /// -/// let dirs = fs::read_dir(".foo").unwrap(); +/// let dirs = fs::read_dir(".foo")?; /// /// // we need to convert from an iterator of DirEntry-s to an iterator of /// // PathBufs, so we use map @@ -50,6 +50,7 @@ use crate::iter::{FusedIterator, TrustedLen}; /// for f in files { /// println!("{f:?}"); /// } +/// # std::io::Result::Ok(()) /// ``` #[stable(feature = "iter_once", since = "1.2.0")] pub fn once(value: T) -> Once { diff --git a/library/core/src/iter/traits/iterator.rs b/library/core/src/iter/traits/iterator.rs index 38dfbbef39323..ff39e8ac25f8f 100644 --- a/library/core/src/iter/traits/iterator.rs +++ b/library/core/src/iter/traits/iterator.rs @@ -2564,7 +2564,7 @@ pub trait Iterator { /// # Example /// /// ``` - /// let reduced: i32 = (1..10).reduce(|acc, e| acc + e).unwrap(); + /// let reduced: i32 = (1..10).reduce(|acc, e| acc + e).unwrap_or(0); /// assert_eq!(reduced, 45); /// /// // Which is equivalent to doing it with `fold`: @@ -3087,7 +3087,7 @@ pub trait Iterator { /// [2.4, f32::NAN, 1.3] /// .into_iter() /// .reduce(f32::max) - /// .unwrap(), + /// .unwrap_or(0.), /// 2.4 /// ); /// ``` @@ -3123,7 +3123,7 @@ pub trait Iterator { /// [2.4, f32::NAN, 1.3] /// .into_iter() /// .reduce(f32::min) - /// .unwrap(), + /// .unwrap_or(0.), /// 1.3 /// ); /// ``` diff --git a/library/core/src/option.rs b/library/core/src/option.rs index f4ac7af63961b..a9f06b92ad5dd 100644 --- a/library/core/src/option.rs +++ b/library/core/src/option.rs @@ -937,10 +937,16 @@ impl Option { /// Returns the contained [`Some`] value, consuming the `self` value. /// /// Because this function may panic, its use is generally discouraged. + /// Panics are meant for unrecoverable errors, and + /// [may abort the entire program][panic-abort]. + /// /// Instead, prefer to use pattern matching and handle the [`None`] /// case explicitly, or call [`unwrap_or`], [`unwrap_or_else`], or - /// [`unwrap_or_default`]. + /// [`unwrap_or_default`]. In functions returning `Option`, you can use + /// [the `?` (try) operator][try-option]. /// + /// [panic-abort]: https://doc.rust-lang.org/book/ch09-01-unrecoverable-errors-with-panic.html + /// [try-option]: https://doc.rust-lang.org/book/ch09-02-recoverable-errors-with-result.html#where-the--operator-can-be-used /// [`unwrap_or`]: Option::unwrap_or /// [`unwrap_or_else`]: Option::unwrap_or_else /// [`unwrap_or_default`]: Option::unwrap_or_default diff --git a/library/core/src/ptr/const_ptr.rs b/library/core/src/ptr/const_ptr.rs index f100adecbbb76..ac905eceaa803 100644 --- a/library/core/src/ptr/const_ptr.rs +++ b/library/core/src/ptr/const_ptr.rs @@ -502,11 +502,12 @@ impl *const T { /// let mut out = String::new(); /// while ptr != end_rounded_up { /// unsafe { - /// write!(&mut out, "{}, ", *ptr).unwrap(); + /// write!(&mut out, "{}, ", *ptr)?; /// } /// ptr = ptr.wrapping_offset(step); /// } /// assert_eq!(out.as_str(), "1, 3, 5, "); + /// # std::fmt::Result::Ok(()) /// ``` #[stable(feature = "ptr_wrapping_offset", since = "1.16.0")] #[must_use = "returns a new pointer rather than modifying its argument"] @@ -1125,11 +1126,12 @@ impl *const T { /// let mut out = String::new(); /// while ptr != end_rounded_up { /// unsafe { - /// write!(&mut out, "{}, ", *ptr).unwrap(); + /// write!(&mut out, "{}, ", *ptr)?; /// } /// ptr = ptr.wrapping_add(step); /// } /// assert_eq!(out, "1, 3, 5, "); + /// # std::fmt::Result::Ok(()) /// ``` #[stable(feature = "pointer_methods", since = "1.26.0")] #[must_use = "returns a new pointer rather than modifying its argument"] @@ -1203,11 +1205,12 @@ impl *const T { /// let mut out = String::new(); /// while ptr != start_rounded_down { /// unsafe { - /// write!(&mut out, "{}, ", *ptr).unwrap(); + /// write!(&mut out, "{}, ", *ptr)?; /// } /// ptr = ptr.wrapping_sub(step); /// } /// assert_eq!(out, "5, 3, 1, "); + /// # std::fmt::Result::Ok(()) /// ``` #[stable(feature = "pointer_methods", since = "1.26.0")] #[must_use = "returns a new pointer rather than modifying its argument"] diff --git a/library/core/src/result.rs b/library/core/src/result.rs index 9c7be618bc773..92b5cba153166 100644 --- a/library/core/src/result.rs +++ b/library/core/src/result.rs @@ -1065,10 +1065,15 @@ impl Result { /// Returns the contained [`Ok`] value, consuming the `self` value. /// /// Because this function may panic, its use is generally discouraged. - /// Instead, prefer to use pattern matching and handle the [`Err`] - /// case explicitly, or call [`unwrap_or`], [`unwrap_or_else`], or - /// [`unwrap_or_default`]. + /// Panics are meant for unrecoverable errors, and + /// [may abort the entire program][panic-abort]. + /// + /// Instead, prefer to use [the `?` (try) operator][try-operator], or pattern matching + /// to handle the [`Err`] case explicitly, or call [`unwrap_or`], + /// [`unwrap_or_else`], or [`unwrap_or_default`]. /// + /// [panic-abort]: https://doc.rust-lang.org/book/ch09-01-unrecoverable-errors-with-panic.html + /// [try-operator]: https://doc.rust-lang.org/book/ch09-02-recoverable-errors-with-result.html#a-shortcut-for-propagating-errors-the--operator /// [`unwrap_or`]: Result::unwrap_or /// [`unwrap_or_else`]: Result::unwrap_or_else /// [`unwrap_or_default`]: Result::unwrap_or_default diff --git a/library/core/src/slice/iter.rs b/library/core/src/slice/iter.rs index a27baf9db224c..d2842f69008e2 100644 --- a/library/core/src/slice/iter.rs +++ b/library/core/src/slice/iter.rs @@ -46,13 +46,19 @@ impl<'a, T> IntoIterator for &'a mut [T] { /// Basic usage: /// /// ``` -/// // First, we declare a type which has `iter` method to get the `Iter` struct (`&[usize]` here): +/// // First, we need a slice to call the `iter` method on: /// let slice = &[1, 2, 3]; /// -/// // Then, we iterate over it: +/// // Then we call `iter` on the slice to get the `Iter` struct, +/// // and iterate over it: /// for element in slice.iter() { /// println!("{element}"); /// } +/// +/// // This for loop actually already works without calling `iter`: +/// for element in slice { +/// println!("{element}"); +/// } /// ``` /// /// [`iter`]: slice::iter @@ -109,19 +115,25 @@ impl<'a, T> Iter<'a, T> { /// Basic usage: /// /// ``` - /// // First, we declare a type which has the `iter` method to get the `Iter` + /// // First, we need a slice to call the `iter` method on: /// // struct (`&[usize]` here): /// let slice = &[1, 2, 3]; /// - /// // Then, we get the iterator: + /// // Then we call `iter` on the slice to get the `Iter` struct: /// let mut iter = slice.iter(); - /// // So if we print what `as_slice` method returns here, we have "[1, 2, 3]": + /// // Here `as_slice` still returns the whole slice, so this prints "[1, 2, 3]": /// println!("{:?}", iter.as_slice()); /// - /// // Next, we move to the second element of the slice: + /// // Now, we call the `next` method to remove the first element of the iterator: /// iter.next(); - /// // Now `as_slice` returns "[2, 3]": + /// // Here the iterator does not contain the first element of the slice any more, + /// // so `as_slice` only returns the last two elements of the slice, + /// // and so this prints "[2, 3]": /// println!("{:?}", iter.as_slice()); + /// + /// // The underlying slice has not been modified and still contains three elements, + /// // so this prints "[1, 2, 3]": + /// println!("{:?}", slice); /// ``` #[must_use] #[stable(feature = "iter_to_slice", since = "1.4.0")] @@ -166,11 +178,11 @@ impl AsRef<[T]> for Iter<'_, T> { /// Basic usage: /// /// ``` -/// // First, we declare a type which has `iter_mut` method to get the `IterMut` -/// // struct (`&[usize]` here): -/// let mut slice = &mut [1, 2, 3]; +/// // First, we need a slice to call the `iter_mut` method on: +/// let slice = &mut [1, 2, 3]; /// -/// // Then, we iterate over it and increment each element value: +/// // Then we call `iter_mut` on the slice to get the `IterMut` struct, +/// // iterate over it and increment each element value: /// for element in slice.iter_mut() { /// *element += 1; /// } @@ -247,28 +259,21 @@ impl<'a, T> IterMut<'a, T> { /// Basic usage: /// /// ``` - /// // First, we declare a type which has `iter_mut` method to get the `IterMut` - /// // struct (`&[usize]` here): + /// // First, we need a slice to call the `iter_mut` method on: /// let mut slice = &mut [1, 2, 3]; /// - /// { - /// // Then, we get the iterator: - /// let mut iter = slice.iter_mut(); - /// // We move to next element: - /// iter.next(); - /// // So if we print what `into_slice` method returns here, we have "[2, 3]": - /// println!("{:?}", iter.into_slice()); - /// } - /// - /// // Now let's modify a value of the slice: - /// { - /// // First we get back the iterator: - /// let mut iter = slice.iter_mut(); - /// // We change the value of the first element of the slice returned by the `next` method: - /// *iter.next().unwrap() += 1; - /// } - /// // Now slice is "[2, 2, 3]": - /// println!("{slice:?}"); + /// // Then we call `iter_mut` on the slice to get the `IterMut` struct: + /// let mut iter = slice.iter_mut(); + /// // Now, we call the `next` method to remove the first element of the iterator, + /// // unwrap and dereference what we get from `next` and increase its value by 1: + /// *iter.next().unwrap() += 1; + /// // Here the iterator does not contain the first element of the slice any more, + /// // so `into_slice` only returns the last two elements of the slice, + /// // and so this prints "[2, 3]": + /// println!("{:?}", iter.into_slice()); + /// // The underlying slice still contains three elements, but its first element + /// // was increased by 1, so this prints "[2, 2, 3]": + /// println!("{:?}", slice); /// ``` #[must_use = "`self` will be dropped if the result is not used"] #[stable(feature = "iter_to_slice", since = "1.4.0")] diff --git a/library/core/src/str/converts.rs b/library/core/src/str/converts.rs index c7bae42765f4e..de68f80aa0c8e 100644 --- a/library/core/src/str/converts.rs +++ b/library/core/src/str/converts.rs @@ -47,10 +47,11 @@ use crate::{mem, ptr}; /// // some bytes, in a vector /// let sparkle_heart = vec![240, 159, 146, 150]; /// -/// // We know these bytes are valid, so just use `unwrap()`. -/// let sparkle_heart = str::from_utf8(&sparkle_heart).unwrap(); +/// // We can use the ? (try) operator to check if the bytes are valid +/// let sparkle_heart = str::from_utf8(&sparkle_heart)?; /// /// assert_eq!("💖", sparkle_heart); +/// # Ok::<_, str::Utf8Error>(()) /// ``` /// /// Incorrect bytes: diff --git a/library/core/src/sync/atomic.rs b/library/core/src/sync/atomic.rs index 487fffba881b3..fda26a672990a 100644 --- a/library/core/src/sync/atomic.rs +++ b/library/core/src/sync/atomic.rs @@ -86,7 +86,7 @@ //! // This is fine: `join` synchronizes the code in a way such that the atomic //! // store happens-before the non-atomic write. //! let handle = s.spawn(|| atomic.store(1, Ordering::Relaxed)); // atomic store -//! handle.join().unwrap(); // synchronize +//! handle.join().expect("thread won't panic"); // synchronize //! s.spawn(|| unsafe { atomic.as_ptr().write(2) }); // non-atomic write //! }); //! @@ -103,7 +103,7 @@ //! // This is fine: `join` synchronizes the code in a way such that //! // the 1-byte store happens-before the 2-byte store. //! let handle = s.spawn(|| atomic.store(1, Ordering::Relaxed)); -//! handle.join().unwrap(); +//! handle.join().expect("thread won't panic"); //! s.spawn(|| unsafe { //! let differently_sized = transmute::<&AtomicU16, &AtomicU8>(&atomic); //! differently_sized.store(2, Ordering::Relaxed); diff --git a/library/std/src/io/mod.rs b/library/std/src/io/mod.rs index 4ffb04630061f..7912f969bbd9f 100644 --- a/library/std/src/io/mod.rs +++ b/library/std/src/io/mod.rs @@ -1083,7 +1083,7 @@ pub trait Read { /// let f = BufReader::new(File::open("foo.txt")?); /// /// for byte in f.bytes() { - /// println!("{}", byte.unwrap()); + /// println!("{}", byte?); /// } /// Ok(()) /// } @@ -1995,15 +1995,16 @@ pub trait Seek { /// .write(true) /// .read(true) /// .create(true) - /// .open("foo.txt").unwrap(); + /// .open("foo.txt")?; /// /// let hello = "Hello!\n"; - /// write!(f, "{hello}").unwrap(); - /// f.rewind().unwrap(); + /// write!(f, "{hello}")?; + /// f.rewind()?; /// /// let mut buf = String::new(); - /// f.read_to_string(&mut buf).unwrap(); + /// f.read_to_string(&mut buf)?; /// assert_eq!(&buf, hello); + /// # std::io::Result::Ok(()) /// ``` #[stable(feature = "seek_rewind", since = "1.55.0")] fn rewind(&mut self) -> Result<()> { @@ -2212,8 +2213,9 @@ fn skip_until(r: &mut R, delim: u8) -> Result { /// /// let stdin = io::stdin(); /// for line in stdin.lock().lines() { -/// println!("{}", line.unwrap()); +/// println!("{}", line?); /// } +/// # std::io::Result::Ok(()) /// ``` /// /// If you have something that implements [`Read`], you can use the [`BufReader` @@ -2236,7 +2238,8 @@ fn skip_until(r: &mut R, delim: u8) -> Result { /// let f = BufReader::new(f); /// /// for line in f.lines() { -/// println!("{}", line.unwrap()); +/// let line = line?; +/// println!("{line}"); /// } /// /// Ok(()) @@ -2274,7 +2277,7 @@ pub trait BufRead: Read { /// let stdin = io::stdin(); /// let mut stdin = stdin.lock(); /// - /// let buffer = stdin.fill_buf().unwrap(); + /// let buffer = stdin.fill_buf()?; /// /// // work with buffer /// println!("{buffer:?}"); @@ -2282,6 +2285,7 @@ pub trait BufRead: Read { /// // ensure the bytes we worked with aren't returned again later /// let length = buffer.len(); /// stdin.consume(length); + /// # std::io::Result::Ok(()) /// ``` #[stable(feature = "rust1", since = "1.0.0")] fn fill_buf(&mut self) -> Result<&[u8]>; @@ -2327,12 +2331,13 @@ pub trait BufRead: Read { /// let stdin = io::stdin(); /// let mut stdin = stdin.lock(); /// - /// while stdin.has_data_left().unwrap() { + /// while stdin.has_data_left()? { /// let mut line = String::new(); - /// stdin.read_line(&mut line).unwrap(); + /// stdin.read_line(&mut line)?; /// // work with line /// println!("{line:?}"); /// } + /// # std::io::Result::Ok(()) /// ``` #[unstable(feature = "buf_read_has_data_left", reason = "recently added", issue = "86423")] fn has_data_left(&mut self) -> Result { diff --git a/library/std/src/process.rs b/library/std/src/process.rs index 6933528cdbd0a..929d2b57afe5c 100644 --- a/library/std/src/process.rs +++ b/library/std/src/process.rs @@ -224,7 +224,7 @@ pub struct Child { /// has been captured. You might find it helpful to do /// /// ```ignore (incomplete) - /// let stdin = child.stdin.take().unwrap(); + /// let stdin = child.stdin.take().expect("handle present"); /// ``` /// /// to avoid partially moving the `child` and thus blocking yourself from calling @@ -236,7 +236,7 @@ pub struct Child { /// has been captured. You might find it helpful to do /// /// ```ignore (incomplete) - /// let stdout = child.stdout.take().unwrap(); + /// let stdout = child.stdout.take().expect("handle present"); /// ``` /// /// to avoid partially moving the `child` and thus blocking yourself from calling @@ -248,7 +248,7 @@ pub struct Child { /// has been captured. You might find it helpful to do /// /// ```ignore (incomplete) - /// let stderr = child.stderr.take().unwrap(); + /// let stderr = child.stderr.take().expect("handle present"); /// ``` /// /// to avoid partially moving the `child` and thus blocking yourself from calling @@ -1052,14 +1052,14 @@ impl Command { /// use std::io::{self, Write}; /// let output = Command::new("/bin/cat") /// .arg("file.txt") - /// .output() - /// .expect("failed to execute process"); + /// .output()?; /// /// println!("status: {}", output.status); - /// io::stdout().write_all(&output.stdout).unwrap(); - /// io::stderr().write_all(&output.stderr).unwrap(); + /// io::stdout().write_all(&output.stdout)?; + /// io::stderr().write_all(&output.stderr)?; /// /// assert!(output.status.success()); + /// # io::Result::Ok(()) /// ``` #[stable(feature = "process", since = "1.0.0")] pub fn output(&mut self) -> io::Result { @@ -1391,11 +1391,11 @@ impl Stdio { /// let output = Command::new("rev") /// .stdin(Stdio::inherit()) /// .stdout(Stdio::piped()) - /// .output() - /// .expect("Failed to execute command"); + /// .output()?; /// /// print!("You piped in the reverse of: "); - /// io::stdout().write_all(&output.stdout).unwrap(); + /// io::stdout().write_all(&output.stdout)?; + /// # io::Result::Ok(()) /// ``` #[must_use] #[stable(feature = "process", since = "1.0.0")] @@ -1575,14 +1575,14 @@ impl From for Stdio { /// use std::process::Command; /// /// // With the `foo.txt` file containing "Hello, world!" - /// let file = File::open("foo.txt").unwrap(); + /// let file = File::open("foo.txt")?; /// /// let reverse = Command::new("rev") /// .stdin(file) // Implicit File conversion into a Stdio - /// .output() - /// .expect("failed reverse command"); + /// .output()?; /// /// assert_eq!(reverse.stdout, b"!dlrow ,olleH"); + /// # std::io::Result::Ok(()) /// ``` fn from(file: fs::File) -> Stdio { Stdio::from_inner(file.into_inner().into()) @@ -2179,7 +2179,7 @@ impl Child { /// ```no_run /// use std::process::Command; /// - /// let mut child = Command::new("ls").spawn().unwrap(); + /// let mut child = Command::new("ls").spawn()?; /// /// match child.try_wait() { /// Ok(Some(status)) => println!("exited with: {status}"), @@ -2190,6 +2190,7 @@ impl Child { /// } /// Err(e) => println!("error attempting to wait: {e}"), /// } + /// # std::io::Result::Ok(()) /// ``` #[stable(feature = "process_try_wait", since = "1.18.0")] pub fn try_wait(&mut self) -> io::Result> { diff --git a/tests/ui-fulldeps/pprust-parenthesis-insertion.rs b/tests/ui-fulldeps/pprust-parenthesis-insertion.rs index 184458bad5551..258a1fdb1d36f 100644 --- a/tests/ui-fulldeps/pprust-parenthesis-insertion.rs +++ b/tests/ui-fulldeps/pprust-parenthesis-insertion.rs @@ -61,6 +61,9 @@ static EXPRS: &[&str] = &[ "(2 + 2) * 2", "2 * (2 + 2)", "2 + 2 + 2", + // Right-associative operator. + "2 += 2 += 2", + "(2 += 2) += 2", // Return has lower precedence than a binary operator. "(return 2) + 2", "2 + (return 2)", // FIXME: no parenthesis needed. @@ -89,6 +92,13 @@ static EXPRS: &[&str] = &[ // allowed, except if the break is also labeled. "break 'outer 'inner: loop {} + 2", "break ('inner: loop {} + 2)", + // Grammar restriction: ranges cannot be the endpoint of another range. + "(2..2)..2", + "2..(2..2)", + "(2..2)..", + "..(2..2)", + // Grammar restriction: comparison operators cannot be chained (1 < 2 == false). + "((1 < 2) == false) as usize", // Grammar restriction: the value in let-else is not allowed to end in a // curly brace. "{ let _ = 1 + 1 else {}; }", @@ -113,10 +123,6 @@ static EXPRS: &[&str] = &[ "if let _ = () && (Struct {}).x {}", */ /* - // FIXME: pretty-printer produces invalid syntax. `(1 < 2 == false) as usize` - "((1 < 2) == false) as usize", - */ - /* // FIXME: pretty-printer produces invalid syntax. `for _ in 1..{ 2 } {}` "for _ in (1..{ 2 }) {}", */ diff --git a/tests/ui/drop/tail_expr_drop_order-on-coroutine-unwind.rs b/tests/ui/drop/tail_expr_drop_order-on-coroutine-unwind.rs new file mode 100644 index 0000000000000..8d85cee19fd07 --- /dev/null +++ b/tests/ui/drop/tail_expr_drop_order-on-coroutine-unwind.rs @@ -0,0 +1,29 @@ +//@ edition: 2021 +//@ build-fail + +// Make sure we don't ICE when emitting the "lint" drop statement +// used for tail_expr_drop_order. + +#![deny(tail_expr_drop_order)] + +struct Drop; +impl std::ops::Drop for Drop { + fn drop(&mut self) {} +} + +async fn func() -> Result<(), Drop> { + todo!() +} + +async fn retry_db() -> Result<(), Drop> { + loop { + match func().await { + //~^ ERROR relative drop order changing in Rust 2024 + //~| WARNING this changes meaning in Rust 2024 + Ok(()) => return Ok(()), + Err(e) => {} + } + } +} + +fn main() {} diff --git a/tests/ui/drop/tail_expr_drop_order-on-coroutine-unwind.stderr b/tests/ui/drop/tail_expr_drop_order-on-coroutine-unwind.stderr new file mode 100644 index 0000000000000..d04abebe14411 --- /dev/null +++ b/tests/ui/drop/tail_expr_drop_order-on-coroutine-unwind.stderr @@ -0,0 +1,52 @@ +error: relative drop order changing in Rust 2024 + --> $DIR/tail_expr_drop_order-on-coroutine-unwind.rs:20:15 + | +LL | match func().await { + | ^^^^^^^----- + | | | + | | this value will be stored in a temporary; let us call it `#1` + | | `#1` will be dropped later as of Edition 2024 + | this value will be stored in a temporary; let us call it `#2` + | up until Edition 2021 `#2` is dropped last but will be dropped earlier in Edition 2024 +... +LL | Err(e) => {} + | - + | | + | `e` calls a custom destructor + | `e` will be dropped later as of Edition 2024 +LL | } +LL | } + | - now the temporary value is dropped here, before the local variables in the block or statement + | + = warning: this changes meaning in Rust 2024 + = note: for more information, see +note: `#2` invokes this custom destructor + --> $DIR/tail_expr_drop_order-on-coroutine-unwind.rs:10:1 + | +LL | / impl std::ops::Drop for Drop { +LL | | fn drop(&mut self) {} +LL | | } + | |_^ +note: `#1` invokes this custom destructor + --> $DIR/tail_expr_drop_order-on-coroutine-unwind.rs:10:1 + | +LL | / impl std::ops::Drop for Drop { +LL | | fn drop(&mut self) {} +LL | | } + | |_^ +note: `e` invokes this custom destructor + --> $DIR/tail_expr_drop_order-on-coroutine-unwind.rs:10:1 + | +LL | / impl std::ops::Drop for Drop { +LL | | fn drop(&mut self) {} +LL | | } + | |_^ + = note: most of the time, changing drop order is harmless; inspect the `impl Drop`s for side effects like releasing locks or sending messages +note: the lint level is defined here + --> $DIR/tail_expr_drop_order-on-coroutine-unwind.rs:7:9 + | +LL | #![deny(tail_expr_drop_order)] + | ^^^^^^^^^^^^^^^^^^^^ + +error: aborting due to 1 previous error + diff --git a/tests/ui/parser/recover/missing-dot-on-statement-expression.fixed b/tests/ui/parser/recover/missing-dot-on-statement-expression.fixed new file mode 100644 index 0000000000000..1be4485b47425 --- /dev/null +++ b/tests/ui/parser/recover/missing-dot-on-statement-expression.fixed @@ -0,0 +1,28 @@ +//@ run-rustfix +#![allow(unused_must_use, dead_code)] +struct S { + field: (), +} +fn main() { + let _ = [1, 2, 3].iter().map(|x| x); //~ ERROR expected one of `.`, `;`, `?`, `else`, or an operator, found `map` + //~^ HELP you might have meant to write a method call +} +fn foo() { + let baz = S { + field: () + }; + let _ = baz.field; //~ ERROR expected one of `!`, `.`, `::`, `;`, `?`, `else`, `{`, or an operator, found `field` + //~^ HELP you might have meant to write a field +} + +fn bar() { + [1, 2, 3].iter().map(|x| x); //~ ERROR expected one of `.`, `;`, `?`, `}`, or an operator, found `map` + //~^ HELP you might have meant to write a method call +} +fn baz() { + let baz = S { + field: () + }; + baz.field; //~ ERROR expected one of `!`, `.`, `::`, `;`, `?`, `{`, `}`, or an operator, found `field` + //~^ HELP you might have meant to write a field +} diff --git a/tests/ui/parser/recover/missing-dot-on-statement-expression.rs b/tests/ui/parser/recover/missing-dot-on-statement-expression.rs new file mode 100644 index 0000000000000..5e2b545f4148d --- /dev/null +++ b/tests/ui/parser/recover/missing-dot-on-statement-expression.rs @@ -0,0 +1,28 @@ +//@ run-rustfix +#![allow(unused_must_use, dead_code)] +struct S { + field: (), +} +fn main() { + let _ = [1, 2, 3].iter()map(|x| x); //~ ERROR expected one of `.`, `;`, `?`, `else`, or an operator, found `map` + //~^ HELP you might have meant to write a method call +} +fn foo() { + let baz = S { + field: () + }; + let _ = baz field; //~ ERROR expected one of `!`, `.`, `::`, `;`, `?`, `else`, `{`, or an operator, found `field` + //~^ HELP you might have meant to write a field +} + +fn bar() { + [1, 2, 3].iter()map(|x| x); //~ ERROR expected one of `.`, `;`, `?`, `}`, or an operator, found `map` + //~^ HELP you might have meant to write a method call +} +fn baz() { + let baz = S { + field: () + }; + baz field; //~ ERROR expected one of `!`, `.`, `::`, `;`, `?`, `{`, `}`, or an operator, found `field` + //~^ HELP you might have meant to write a field +} diff --git a/tests/ui/parser/recover/missing-dot-on-statement-expression.stderr b/tests/ui/parser/recover/missing-dot-on-statement-expression.stderr new file mode 100644 index 0000000000000..a04d8bd34e243 --- /dev/null +++ b/tests/ui/parser/recover/missing-dot-on-statement-expression.stderr @@ -0,0 +1,46 @@ +error: expected one of `.`, `;`, `?`, `else`, or an operator, found `map` + --> $DIR/missing-dot-on-statement-expression.rs:7:29 + | +LL | let _ = [1, 2, 3].iter()map(|x| x); + | ^^^ expected one of `.`, `;`, `?`, `else`, or an operator + | +help: you might have meant to write a method call + | +LL | let _ = [1, 2, 3].iter().map(|x| x); + | + + +error: expected one of `!`, `.`, `::`, `;`, `?`, `else`, `{`, or an operator, found `field` + --> $DIR/missing-dot-on-statement-expression.rs:14:17 + | +LL | let _ = baz field; + | ^^^^^ expected one of 8 possible tokens + | +help: you might have meant to write a field access + | +LL | let _ = baz.field; + | + + +error: expected one of `.`, `;`, `?`, `}`, or an operator, found `map` + --> $DIR/missing-dot-on-statement-expression.rs:19:21 + | +LL | [1, 2, 3].iter()map(|x| x); + | ^^^ expected one of `.`, `;`, `?`, `}`, or an operator + | +help: you might have meant to write a method call + | +LL | [1, 2, 3].iter().map(|x| x); + | + + +error: expected one of `!`, `.`, `::`, `;`, `?`, `{`, `}`, or an operator, found `field` + --> $DIR/missing-dot-on-statement-expression.rs:26:9 + | +LL | baz field; + | ^^^^^ expected one of 8 possible tokens + | +help: you might have meant to write a field access + | +LL | baz.field; + | + + +error: aborting due to 4 previous errors + diff --git a/tests/ui/suggestions/type-ascription-and-other-error.stderr b/tests/ui/suggestions/type-ascription-and-other-error.stderr index 4efddca4b4714..7f8b8b7470eac 100644 --- a/tests/ui/suggestions/type-ascription-and-other-error.stderr +++ b/tests/ui/suggestions/type-ascription-and-other-error.stderr @@ -3,6 +3,11 @@ error: expected one of `!`, `.`, `::`, `;`, `?`, `{`, `}`, or an operator, found | LL | not rust; | ^^^^ expected one of 8 possible tokens + | +help: you might have meant to write a field access + | +LL | not.rust; + | + error: aborting due to 1 previous error