From ed7dc9daf6dc5c397aaaaf70d2733358b0ed6662 Mon Sep 17 00:00:00 2001 From: Dylan DPC Date: Thu, 3 Mar 2022 20:31:35 +0100 Subject: [PATCH] Revert "Parse `Ty?` as `Option` and provide structured suggestion" This reverts commit cfc0bd12581651e5d0f51d0d4c2d8306cc13cb51. --- .../rustc_parse/src/parser/diagnostics.rs | 30 +------------------ compiler/rustc_parse/src/parser/expr.rs | 4 +-- compiler/rustc_parse/src/parser/ty.rs | 26 ---------------- .../issues/issue-35813-postfix-after-cast.rs | 4 +-- .../issue-35813-postfix-after-cast.stderr | 4 +-- src/test/ui/parser/issues/issue-84148-1.rs | 5 ++-- .../ui/parser/issues/issue-84148-1.stderr | 18 ++++++----- src/test/ui/parser/issues/issue-84148-2.rs | 3 +- .../ui/parser/issues/issue-84148-2.stderr | 24 ++++++++------- .../ui/parser/trailing-question-in-type.fixed | 10 ------- .../ui/parser/trailing-question-in-type.rs | 10 ------- .../parser/trailing-question-in-type.stderr | 24 --------------- 12 files changed, 37 insertions(+), 125 deletions(-) delete mode 100644 src/test/ui/parser/trailing-question-in-type.fixed delete mode 100644 src/test/ui/parser/trailing-question-in-type.rs delete mode 100644 src/test/ui/parser/trailing-question-in-type.stderr diff --git a/compiler/rustc_parse/src/parser/diagnostics.rs b/compiler/rustc_parse/src/parser/diagnostics.rs index def23005fbe11..1b02c9be04215 100644 --- a/compiler/rustc_parse/src/parser/diagnostics.rs +++ b/compiler/rustc_parse/src/parser/diagnostics.rs @@ -1,5 +1,5 @@ use super::pat::Expected; -use super::ty::{AllowPlus, IsAsCast}; +use super::ty::AllowPlus; use super::{ BlockMode, Parser, PathStyle, RecoverColon, RecoverComma, Restrictions, SemiColonMode, SeqSep, TokenExpectType, TokenType, @@ -1033,34 +1033,6 @@ impl<'a> Parser<'a> { } } - /// Swift lets users write `Ty?` to mean `Option`. Parse the construct and recover from it. - pub(super) fn maybe_recover_from_question_mark( - &mut self, - ty: P, - is_as_cast: IsAsCast, - ) -> P { - if let IsAsCast::Yes = is_as_cast { - return ty; - } - if self.token == token::Question { - self.bump(); - self.struct_span_err(self.prev_token.span, "invalid `?` in type") - .span_label(self.prev_token.span, "`?` is only allowed on expressions, not types") - .multipart_suggestion( - "if you meant to express that the type might not contain a value, use the `Option` wrapper type", - vec![ - (ty.span.shrink_to_lo(), "Option<".to_string()), - (self.prev_token.span, ">".to_string()), - ], - Applicability::MachineApplicable, - ) - .emit(); - self.mk_ty(ty.span.to(self.prev_token.span), TyKind::Err) - } else { - ty - } - } - pub(super) fn maybe_recover_from_bad_type_plus( &mut self, allow_plus: AllowPlus, diff --git a/compiler/rustc_parse/src/parser/expr.rs b/compiler/rustc_parse/src/parser/expr.rs index 7cb8c35b868a5..1c1b746015dad 100644 --- a/compiler/rustc_parse/src/parser/expr.rs +++ b/compiler/rustc_parse/src/parser/expr.rs @@ -682,7 +682,7 @@ impl<'a> Parser<'a> { // Save the state of the parser before parsing type normally, in case there is a // LessThan comparison after this cast. let parser_snapshot_before_type = self.clone(); - let cast_expr = match self.parse_as_cast_ty() { + let cast_expr = match self.parse_ty_no_plus() { Ok(rhs) => mk_expr(self, lhs, rhs), Err(mut type_err) => { // Rewind to before attempting to parse the type with generics, to recover @@ -808,7 +808,7 @@ impl<'a> Parser<'a> { "casts cannot be followed by {}", match with_postfix.kind { ExprKind::Index(_, _) => "indexing", - ExprKind::Try(_) => "`?`", + ExprKind::Try(_) => "?", ExprKind::Field(_, _) => "a field access", ExprKind::MethodCall(_, _, _) => "a method call", ExprKind::Call(_, _) => "a function call", diff --git a/compiler/rustc_parse/src/parser/ty.rs b/compiler/rustc_parse/src/parser/ty.rs index 566b77a5e9e55..02a774ba1291c 100644 --- a/compiler/rustc_parse/src/parser/ty.rs +++ b/compiler/rustc_parse/src/parser/ty.rs @@ -44,11 +44,6 @@ pub(super) enum RecoverQPath { No, } -pub(super) enum IsAsCast { - Yes, - No, -} - /// Signals whether parsing a type should recover `->`. /// /// More specifically, when parsing a function like: @@ -105,7 +100,6 @@ impl<'a> Parser<'a> { RecoverQPath::Yes, RecoverReturnSign::Yes, None, - IsAsCast::No, ) } @@ -119,7 +113,6 @@ impl<'a> Parser<'a> { RecoverQPath::Yes, RecoverReturnSign::Yes, Some(ty_params), - IsAsCast::No, ) } @@ -133,7 +126,6 @@ impl<'a> Parser<'a> { RecoverQPath::Yes, RecoverReturnSign::Yes, None, - IsAsCast::No, ) } @@ -150,22 +142,9 @@ impl<'a> Parser<'a> { RecoverQPath::Yes, RecoverReturnSign::Yes, None, - IsAsCast::No, ) } - /// Parses a type following an `as` cast. Similar to `parse_ty_no_plus`, but signaling origin - /// for better diagnostics involving `?`. - pub(super) fn parse_as_cast_ty(&mut self) -> PResult<'a, P> { - self.parse_ty_common( - AllowPlus::No, - AllowCVariadic::No, - RecoverQPath::Yes, - RecoverReturnSign::Yes, - None, - IsAsCast::Yes, - ) - } /// Parse a type without recovering `:` as `->` to avoid breaking code such as `where fn() : for<'a>` pub(super) fn parse_ty_for_where_clause(&mut self) -> PResult<'a, P> { self.parse_ty_common( @@ -174,7 +153,6 @@ impl<'a> Parser<'a> { RecoverQPath::Yes, RecoverReturnSign::OnlyFatArrow, None, - IsAsCast::No, ) } @@ -193,7 +171,6 @@ impl<'a> Parser<'a> { recover_qpath, recover_return_sign, None, - IsAsCast::No, )?; FnRetTy::Ty(ty) } else if recover_return_sign.can_recover(&self.token.kind) { @@ -214,7 +191,6 @@ impl<'a> Parser<'a> { recover_qpath, recover_return_sign, None, - IsAsCast::No, )?; FnRetTy::Ty(ty) } else { @@ -229,7 +205,6 @@ impl<'a> Parser<'a> { recover_qpath: RecoverQPath, recover_return_sign: RecoverReturnSign, ty_generics: Option<&Generics>, - is_as_cast: IsAsCast, ) -> PResult<'a, P> { let allow_qpath_recovery = recover_qpath == RecoverQPath::Yes; maybe_recover_from_interpolated_ty_qpath!(self, allow_qpath_recovery); @@ -305,7 +280,6 @@ impl<'a> Parser<'a> { // Try to recover from use of `+` with incorrect priority. self.maybe_report_ambiguous_plus(allow_plus, impl_dyn_multi, &ty); self.maybe_recover_from_bad_type_plus(allow_plus, &ty)?; - let ty = self.maybe_recover_from_question_mark(ty, is_as_cast); self.maybe_recover_from_bad_qpath(ty, allow_qpath_recovery) } diff --git a/src/test/ui/parser/issues/issue-35813-postfix-after-cast.rs b/src/test/ui/parser/issues/issue-35813-postfix-after-cast.rs index 23f245a51681b..e725aa5d73d1f 100644 --- a/src/test/ui/parser/issues/issue-35813-postfix-after-cast.rs +++ b/src/test/ui/parser/issues/issue-35813-postfix-after-cast.rs @@ -117,9 +117,9 @@ static bar2: &[i32] = &(&[1i32,2,3]: &[i32; 3][0..1]); pub fn cast_then_try() -> Result { Err(0u64) as Result?; - //~^ ERROR: casts cannot be followed by `?` + //~^ ERROR: casts cannot be followed by ? Err(0u64): Result?; - //~^ ERROR: casts cannot be followed by `?` + //~^ ERROR: casts cannot be followed by ? Ok(1) } diff --git a/src/test/ui/parser/issues/issue-35813-postfix-after-cast.stderr b/src/test/ui/parser/issues/issue-35813-postfix-after-cast.stderr index e96b67da3364d..19b68556d79ad 100644 --- a/src/test/ui/parser/issues/issue-35813-postfix-after-cast.stderr +++ b/src/test/ui/parser/issues/issue-35813-postfix-after-cast.stderr @@ -265,7 +265,7 @@ help: try surrounding the expression in parentheses LL | static bar2: &[i32] = &((&[1i32,2,3]: &[i32; 3])[0..1]); | + + -error: casts cannot be followed by `?` +error: casts cannot be followed by ? --> $DIR/issue-35813-postfix-after-cast.rs:119:5 | LL | Err(0u64) as Result?; @@ -276,7 +276,7 @@ help: try surrounding the expression in parentheses LL | (Err(0u64) as Result)?; | + + -error: casts cannot be followed by `?` +error: casts cannot be followed by ? --> $DIR/issue-35813-postfix-after-cast.rs:121:5 | LL | Err(0u64): Result?; diff --git a/src/test/ui/parser/issues/issue-84148-1.rs b/src/test/ui/parser/issues/issue-84148-1.rs index 9fa8086c2c9bf..25f7ba4d1f88e 100644 --- a/src/test/ui/parser/issues/issue-84148-1.rs +++ b/src/test/ui/parser/issues/issue-84148-1.rs @@ -1,3 +1,4 @@ fn f(t:for<>t?) -//~^ ERROR: expected one of -//~| ERROR: invalid `?` in type +//~^ ERROR: expected parameter name +//~| ERROR: expected one of +//~| ERROR: expected one of diff --git a/src/test/ui/parser/issues/issue-84148-1.stderr b/src/test/ui/parser/issues/issue-84148-1.stderr index 9261067c22158..77f0896e9c155 100644 --- a/src/test/ui/parser/issues/issue-84148-1.stderr +++ b/src/test/ui/parser/issues/issue-84148-1.stderr @@ -1,13 +1,17 @@ -error: invalid `?` in type +error: expected parameter name, found `?` --> $DIR/issue-84148-1.rs:1:14 | LL | fn f(t:for<>t?) - | ^ `?` is only allowed on expressions, not types - | -help: if you meant to express that the type might not contain a value, use the `Option` wrapper type + | ^ expected parameter name + +error: expected one of `(`, `)`, `+`, `,`, `::`, or `<`, found `?` + --> $DIR/issue-84148-1.rs:1:14 | -LL | fn f(t:Optiont>) - | +++++++ ~ +LL | fn f(t:for<>t?) + | ^ + | | + | expected one of `(`, `)`, `+`, `,`, `::`, or `<` + | help: missing `,` error: expected one of `->`, `where`, or `{`, found `` --> $DIR/issue-84148-1.rs:1:15 @@ -15,5 +19,5 @@ error: expected one of `->`, `where`, or `{`, found `` LL | fn f(t:for<>t?) | ^ expected one of `->`, `where`, or `{` -error: aborting due to 2 previous errors +error: aborting due to 3 previous errors diff --git a/src/test/ui/parser/issues/issue-84148-2.rs b/src/test/ui/parser/issues/issue-84148-2.rs index 2f6a7facfb271..257a3fd67207e 100644 --- a/src/test/ui/parser/issues/issue-84148-2.rs +++ b/src/test/ui/parser/issues/issue-84148-2.rs @@ -1,3 +1,4 @@ // error-pattern: this file contains an unclosed delimiter -// error-pattern: invalid `?` in type +// error-pattern: expected parameter name +// error-pattern: expected one of fn f(t:for<>t? diff --git a/src/test/ui/parser/issues/issue-84148-2.stderr b/src/test/ui/parser/issues/issue-84148-2.stderr index 71d543f9b7344..396208316df67 100644 --- a/src/test/ui/parser/issues/issue-84148-2.stderr +++ b/src/test/ui/parser/issues/issue-84148-2.stderr @@ -1,27 +1,31 @@ error: this file contains an unclosed delimiter - --> $DIR/issue-84148-2.rs:3:16 + --> $DIR/issue-84148-2.rs:4:16 | LL | fn f(t:for<>t? | - ^ | | | unclosed delimiter -error: invalid `?` in type - --> $DIR/issue-84148-2.rs:3:14 +error: expected parameter name, found `?` + --> $DIR/issue-84148-2.rs:4:14 | LL | fn f(t:for<>t? - | ^ `?` is only allowed on expressions, not types - | -help: if you meant to express that the type might not contain a value, use the `Option` wrapper type + | ^ expected parameter name + +error: expected one of `(`, `)`, `+`, `,`, `::`, or `<`, found `?` + --> $DIR/issue-84148-2.rs:4:14 | -LL | fn f(t:Optiont> - | +++++++ ~ +LL | fn f(t:for<>t? + | ^ + | | + | expected one of `(`, `)`, `+`, `,`, `::`, or `<` + | help: missing `,` error: expected one of `->`, `where`, or `{`, found `` - --> $DIR/issue-84148-2.rs:3:16 + --> $DIR/issue-84148-2.rs:4:16 | LL | fn f(t:for<>t? | ^ expected one of `->`, `where`, or `{` -error: aborting due to 3 previous errors +error: aborting due to 4 previous errors diff --git a/src/test/ui/parser/trailing-question-in-type.fixed b/src/test/ui/parser/trailing-question-in-type.fixed deleted file mode 100644 index 6ea24484e033e..0000000000000 --- a/src/test/ui/parser/trailing-question-in-type.fixed +++ /dev/null @@ -1,10 +0,0 @@ -// run-rustfix - -fn foo() -> Option { //~ ERROR invalid `?` in type - let x: Option = Some(1); //~ ERROR invalid `?` in type - x -} - -fn main() { - let _: Option = foo(); -} diff --git a/src/test/ui/parser/trailing-question-in-type.rs b/src/test/ui/parser/trailing-question-in-type.rs deleted file mode 100644 index b1c508365cff5..0000000000000 --- a/src/test/ui/parser/trailing-question-in-type.rs +++ /dev/null @@ -1,10 +0,0 @@ -// run-rustfix - -fn foo() -> i32? { //~ ERROR invalid `?` in type - let x: i32? = Some(1); //~ ERROR invalid `?` in type - x -} - -fn main() { - let _: Option = foo(); -} diff --git a/src/test/ui/parser/trailing-question-in-type.stderr b/src/test/ui/parser/trailing-question-in-type.stderr deleted file mode 100644 index a3cd419c0c718..0000000000000 --- a/src/test/ui/parser/trailing-question-in-type.stderr +++ /dev/null @@ -1,24 +0,0 @@ -error: invalid `?` in type - --> $DIR/trailing-question-in-type.rs:3:16 - | -LL | fn foo() -> i32? { - | ^ `?` is only allowed on expressions, not types - | -help: if you meant to express that the type might not contain a value, use the `Option` wrapper type - | -LL | fn foo() -> Option { - | +++++++ ~ - -error: invalid `?` in type - --> $DIR/trailing-question-in-type.rs:4:15 - | -LL | let x: i32? = Some(1); - | ^ `?` is only allowed on expressions, not types - | -help: if you meant to express that the type might not contain a value, use the `Option` wrapper type - | -LL | let x: Option = Some(1); - | +++++++ ~ - -error: aborting due to 2 previous errors -