From b011a0a13b4354080b3add0bb3f4445ddb8fd13b Mon Sep 17 00:00:00 2001 From: Matthew Jasper Date: Mon, 11 Sep 2023 16:16:59 +0000 Subject: [PATCH] Reduce double errors for invalid let expressions Previously some invalid let expressions would result in both a feature error and a parsing error. Avoid this and ensure that we only emit the parsing error when this happens. --- compiler/rustc_parse/src/parser/expr.rs | 5 +- tests/ui/expr/if/bad-if-let-suggestion.rs | 1 - tests/ui/expr/if/bad-if-let-suggestion.stderr | 21 +- .../rfc-2294-if-let-guard/feature-gate.rs | 9 - .../rfc-2294-if-let-guard/feature-gate.stderr | 143 +-- ...sallowed-positions-without-feature-gate.rs | 340 +++++++ ...owed-positions-without-feature-gate.stderr | 870 ++++++++++++++++++ 7 files changed, 1249 insertions(+), 140 deletions(-) create mode 100644 tests/ui/rfcs/rfc-2497-if-let-chains/disallowed-positions-without-feature-gate.rs create mode 100644 tests/ui/rfcs/rfc-2497-if-let-chains/disallowed-positions-without-feature-gate.stderr diff --git a/compiler/rustc_parse/src/parser/expr.rs b/compiler/rustc_parse/src/parser/expr.rs index 82701a8b5d5..43cd8fe55df 100644 --- a/compiler/rustc_parse/src/parser/expr.rs +++ b/compiler/rustc_parse/src/parser/expr.rs @@ -2485,9 +2485,6 @@ impl<'a> Parser<'a> { } let expr = self.parse_expr_assoc_with(1 + prec_let_scrutinee_needs_par(), None.into())?; let span = lo.to(expr.span); - if is_recovered.is_none() { - self.sess.gated_spans.gate(sym::let_chains, span); - } Ok(self.mk_expr(span, ExprKind::Let(pat, expr, span, is_recovered))) } @@ -3460,6 +3457,8 @@ impl MutVisitor for CondChecker<'_> { .sess .emit_err(errors::ExpectedExpressionFoundLet { span, reason }), ); + } else { + self.parser.sess.gated_spans.gate(sym::let_chains, span); } } ExprKind::Binary(Spanned { node: BinOpKind::And, .. }, _, _) => { diff --git a/tests/ui/expr/if/bad-if-let-suggestion.rs b/tests/ui/expr/if/bad-if-let-suggestion.rs index 1ff9f3fa3d0..99d584ac7a5 100644 --- a/tests/ui/expr/if/bad-if-let-suggestion.rs +++ b/tests/ui/expr/if/bad-if-let-suggestion.rs @@ -4,7 +4,6 @@ fn a() { if let x = 1 && i = 2 {} //~^ ERROR cannot find value `i` in this scope - //~| ERROR `let` expressions in this position are unstable //~| ERROR mismatched types //~| ERROR expected expression, found `let` statement } diff --git a/tests/ui/expr/if/bad-if-let-suggestion.stderr b/tests/ui/expr/if/bad-if-let-suggestion.stderr index a2367c59040..dc013155e81 100644 --- a/tests/ui/expr/if/bad-if-let-suggestion.stderr +++ b/tests/ui/expr/if/bad-if-let-suggestion.stderr @@ -11,7 +11,7 @@ LL | if let x = 1 && i = 2 {} | ^ not found in this scope error[E0425]: cannot find value `i` in this scope - --> $DIR/bad-if-let-suggestion.rs:13:9 + --> $DIR/bad-if-let-suggestion.rs:12:9 | LL | fn a() { | ------ similarly named function `a` defined here @@ -20,7 +20,7 @@ LL | if (i + j) = i {} | ^ help: a function with a similar name exists: `a` error[E0425]: cannot find value `j` in this scope - --> $DIR/bad-if-let-suggestion.rs:13:13 + --> $DIR/bad-if-let-suggestion.rs:12:13 | LL | fn a() { | ------ similarly named function `a` defined here @@ -29,7 +29,7 @@ LL | if (i + j) = i {} | ^ help: a function with a similar name exists: `a` error[E0425]: cannot find value `i` in this scope - --> $DIR/bad-if-let-suggestion.rs:13:18 + --> $DIR/bad-if-let-suggestion.rs:12:18 | LL | fn a() { | ------ similarly named function `a` defined here @@ -38,7 +38,7 @@ LL | if (i + j) = i {} | ^ help: a function with a similar name exists: `a` error[E0425]: cannot find value `x` in this scope - --> $DIR/bad-if-let-suggestion.rs:20:8 + --> $DIR/bad-if-let-suggestion.rs:19:8 | LL | fn a() { | ------ similarly named function `a` defined here @@ -46,15 +46,6 @@ LL | fn a() { LL | if x[0] = 1 {} | ^ help: a function with a similar name exists: `a` -error[E0658]: `let` expressions in this position are unstable - --> $DIR/bad-if-let-suggestion.rs:5:8 - | -LL | if let x = 1 && i = 2 {} - | ^^^^^^^^^ - | - = note: see issue #53667 for more information - = help: add `#![feature(let_chains)]` to the crate attributes to enable - error[E0308]: mismatched types --> $DIR/bad-if-let-suggestion.rs:5:8 | @@ -66,7 +57,7 @@ help: you might have meant to compare for equality LL | if let x = 1 && i == 2 {} | + -error: aborting due to 8 previous errors +error: aborting due to 7 previous errors -Some errors have detailed explanations: E0308, E0425, E0658. +Some errors have detailed explanations: E0308, E0425. For more information about an error, try `rustc --explain E0308`. diff --git a/tests/ui/rfcs/rfc-2294-if-let-guard/feature-gate.rs b/tests/ui/rfcs/rfc-2294-if-let-guard/feature-gate.rs index 21f2a41cb1b..b8c0eb3e6d6 100644 --- a/tests/ui/rfcs/rfc-2294-if-let-guard/feature-gate.rs +++ b/tests/ui/rfcs/rfc-2294-if-let-guard/feature-gate.rs @@ -9,11 +9,9 @@ fn _if_let_guard() { () if (let 0 = 1) => {} //~^ ERROR expected expression, found `let` statement - //~| ERROR `let` expressions in this position are unstable () if (((let 0 = 1))) => {} //~^ ERROR expected expression, found `let` statement - //~| ERROR `let` expressions in this position are unstable () if true && let 0 = 1 => {} //~^ ERROR `if let` guards are experimental @@ -25,25 +23,18 @@ fn _if_let_guard() { () if (let 0 = 1) && true => {} //~^ ERROR expected expression, found `let` statement - //~| ERROR `let` expressions in this position are unstable () if true && (let 0 = 1) => {} //~^ ERROR expected expression, found `let` statement - //~| ERROR `let` expressions in this position are unstable () if (let 0 = 1) && (let 0 = 1) => {} //~^ ERROR expected expression, found `let` statement //~| ERROR expected expression, found `let` statement - //~| ERROR `let` expressions in this position are unstable - //~| ERROR `let` expressions in this position are unstable () if let 0 = 1 && let 1 = 2 && (let 2 = 3 && let 3 = 4 && let 4 = 5) => {} //~^ ERROR `if let` guards are experimental //~| ERROR `let` expressions in this position are unstable //~| ERROR `let` expressions in this position are unstable - //~| ERROR `let` expressions in this position are unstable - //~| ERROR `let` expressions in this position are unstable - //~| ERROR `let` expressions in this position are unstable //~| ERROR expected expression, found `let` statement //~| ERROR expected expression, found `let` statement //~| ERROR expected expression, found `let` statement diff --git a/tests/ui/rfcs/rfc-2294-if-let-guard/feature-gate.stderr b/tests/ui/rfcs/rfc-2294-if-let-guard/feature-gate.stderr index d5187ba1afc..a21ecae4eae 100644 --- a/tests/ui/rfcs/rfc-2294-if-let-guard/feature-gate.stderr +++ b/tests/ui/rfcs/rfc-2294-if-let-guard/feature-gate.stderr @@ -11,115 +11,115 @@ LL | () if (let 0 = 1) => {} | ^^^^^^^^^ error: expected expression, found `let` statement - --> $DIR/feature-gate.rs:14:18 + --> $DIR/feature-gate.rs:13:18 | LL | () if (((let 0 = 1))) => {} | ^^^^^^^^^ | note: `let`s wrapped in parentheses are not supported in a context with let chains - --> $DIR/feature-gate.rs:14:18 + --> $DIR/feature-gate.rs:13:18 | LL | () if (((let 0 = 1))) => {} | ^^^^^^^^^ error: expected expression, found `let` statement - --> $DIR/feature-gate.rs:26:16 + --> $DIR/feature-gate.rs:24:16 | LL | () if (let 0 = 1) && true => {} | ^^^^^^^^^ | note: `let`s wrapped in parentheses are not supported in a context with let chains - --> $DIR/feature-gate.rs:26:16 + --> $DIR/feature-gate.rs:24:16 | LL | () if (let 0 = 1) && true => {} | ^^^^^^^^^ error: expected expression, found `let` statement - --> $DIR/feature-gate.rs:30:24 + --> $DIR/feature-gate.rs:27:24 | LL | () if true && (let 0 = 1) => {} | ^^^^^^^^^ | note: `let`s wrapped in parentheses are not supported in a context with let chains - --> $DIR/feature-gate.rs:30:24 + --> $DIR/feature-gate.rs:27:24 | LL | () if true && (let 0 = 1) => {} | ^^^^^^^^^ error: expected expression, found `let` statement - --> $DIR/feature-gate.rs:34:16 + --> $DIR/feature-gate.rs:30:16 | LL | () if (let 0 = 1) && (let 0 = 1) => {} | ^^^^^^^^^ | note: `let`s wrapped in parentheses are not supported in a context with let chains - --> $DIR/feature-gate.rs:34:16 + --> $DIR/feature-gate.rs:30:16 | LL | () if (let 0 = 1) && (let 0 = 1) => {} | ^^^^^^^^^ error: expected expression, found `let` statement - --> $DIR/feature-gate.rs:34:31 + --> $DIR/feature-gate.rs:30:31 | LL | () if (let 0 = 1) && (let 0 = 1) => {} | ^^^^^^^^^ | note: `let`s wrapped in parentheses are not supported in a context with let chains - --> $DIR/feature-gate.rs:34:31 + --> $DIR/feature-gate.rs:30:31 | LL | () if (let 0 = 1) && (let 0 = 1) => {} | ^^^^^^^^^ error: expected expression, found `let` statement - --> $DIR/feature-gate.rs:40:42 + --> $DIR/feature-gate.rs:34:42 | LL | () if let 0 = 1 && let 1 = 2 && (let 2 = 3 && let 3 = 4 && let 4 = 5) => {} | ^^^^^^^^^ | note: `let`s wrapped in parentheses are not supported in a context with let chains - --> $DIR/feature-gate.rs:40:42 + --> $DIR/feature-gate.rs:34:42 | LL | () if let 0 = 1 && let 1 = 2 && (let 2 = 3 && let 3 = 4 && let 4 = 5) => {} | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ error: expected expression, found `let` statement - --> $DIR/feature-gate.rs:40:55 + --> $DIR/feature-gate.rs:34:55 | LL | () if let 0 = 1 && let 1 = 2 && (let 2 = 3 && let 3 = 4 && let 4 = 5) => {} | ^^^^^^^^^ | note: `let`s wrapped in parentheses are not supported in a context with let chains - --> $DIR/feature-gate.rs:40:42 + --> $DIR/feature-gate.rs:34:42 | LL | () if let 0 = 1 && let 1 = 2 && (let 2 = 3 && let 3 = 4 && let 4 = 5) => {} | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ error: expected expression, found `let` statement - --> $DIR/feature-gate.rs:40:68 + --> $DIR/feature-gate.rs:34:68 | LL | () if let 0 = 1 && let 1 = 2 && (let 2 = 3 && let 3 = 4 && let 4 = 5) => {} | ^^^^^^^^^ | note: `let`s wrapped in parentheses are not supported in a context with let chains - --> $DIR/feature-gate.rs:40:42 + --> $DIR/feature-gate.rs:34:42 | LL | () if let 0 = 1 && let 1 = 2 && (let 2 = 3 && let 3 = 4 && let 4 = 5) => {} | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ error: expected expression, found `let` statement - --> $DIR/feature-gate.rs:69:16 + --> $DIR/feature-gate.rs:60:16 | LL | use_expr!((let 0 = 1 && 0 == 0)); | ^^^ error: expected expression, found `let` statement - --> $DIR/feature-gate.rs:71:16 + --> $DIR/feature-gate.rs:62:16 | LL | use_expr!((let 0 = 1)); | ^^^ error: no rules expected the token `let` - --> $DIR/feature-gate.rs:79:15 + --> $DIR/feature-gate.rs:70:15 | LL | macro_rules! use_expr { | --------------------- when calling this macro @@ -128,7 +128,7 @@ LL | use_expr!(let 0 = 1); | ^^^ no rules expected this token in macro call | note: while trying to match meta-variable `$e:expr` - --> $DIR/feature-gate.rs:62:10 + --> $DIR/feature-gate.rs:53:10 | LL | ($e:expr) => { | ^^^^^^^ @@ -144,7 +144,7 @@ LL | () if let 0 = 1 => {} = help: you can write `if matches!(, )` instead of `if let = ` error[E0658]: `if let` guards are experimental - --> $DIR/feature-gate.rs:18:12 + --> $DIR/feature-gate.rs:16:12 | LL | () if true && let 0 = 1 => {} | ^^^^^^^^^^^^^^^^^^^^ @@ -154,7 +154,7 @@ LL | () if true && let 0 = 1 => {} = help: you can write `if matches!(, )` instead of `if let = ` error[E0658]: `if let` guards are experimental - --> $DIR/feature-gate.rs:22:12 + --> $DIR/feature-gate.rs:20:12 | LL | () if let 0 = 1 && true => {} | ^^^^^^^^^^^^^^^^^^^^ @@ -164,7 +164,7 @@ LL | () if let 0 = 1 && true => {} = help: you can write `if matches!(, )` instead of `if let = ` error[E0658]: `if let` guards are experimental - --> $DIR/feature-gate.rs:40:12 + --> $DIR/feature-gate.rs:34:12 | LL | () if let 0 = 1 && let 1 = 2 && (let 2 = 3 && let 3 = 4 && let 4 = 5) => {} | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ @@ -174,7 +174,7 @@ LL | () if let 0 = 1 && let 1 = 2 && (let 2 = 3 && let 3 = 4 && let 4 = = help: you can write `if matches!(, )` instead of `if let = ` error[E0658]: `if let` guards are experimental - --> $DIR/feature-gate.rs:52:12 + --> $DIR/feature-gate.rs:43:12 | LL | () if let Range { start: _, end: _ } = (true..true) && false => {} | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ @@ -184,7 +184,7 @@ LL | () if let Range { start: _, end: _ } = (true..true) && false => {} = help: you can write `if matches!(, )` instead of `if let = ` error[E0658]: `if let` guards are experimental - --> $DIR/feature-gate.rs:75:12 + --> $DIR/feature-gate.rs:66:12 | LL | () if let 0 = 1 => {} | ^^^^^^^^^^^^ @@ -194,25 +194,7 @@ LL | () if let 0 = 1 => {} = help: you can write `if matches!(, )` instead of `if let = ` error[E0658]: `let` expressions in this position are unstable - --> $DIR/feature-gate.rs:10:16 - | -LL | () if (let 0 = 1) => {} - | ^^^^^^^^^ - | - = note: see issue #53667 for more information - = help: add `#![feature(let_chains)]` to the crate attributes to enable - -error[E0658]: `let` expressions in this position are unstable - --> $DIR/feature-gate.rs:14:18 - | -LL | () if (((let 0 = 1))) => {} - | ^^^^^^^^^ - | - = note: see issue #53667 for more information - = help: add `#![feature(let_chains)]` to the crate attributes to enable - -error[E0658]: `let` expressions in this position are unstable - --> $DIR/feature-gate.rs:18:23 + --> $DIR/feature-gate.rs:16:23 | LL | () if true && let 0 = 1 => {} | ^^^^^^^^^ @@ -221,7 +203,7 @@ LL | () if true && let 0 = 1 => {} = help: add `#![feature(let_chains)]` to the crate attributes to enable error[E0658]: `let` expressions in this position are unstable - --> $DIR/feature-gate.rs:22:15 + --> $DIR/feature-gate.rs:20:15 | LL | () if let 0 = 1 && true => {} | ^^^^^^^^^ @@ -230,43 +212,7 @@ LL | () if let 0 = 1 && true => {} = help: add `#![feature(let_chains)]` to the crate attributes to enable error[E0658]: `let` expressions in this position are unstable - --> $DIR/feature-gate.rs:26:16 - | -LL | () if (let 0 = 1) && true => {} - | ^^^^^^^^^ - | - = note: see issue #53667 for more information - = help: add `#![feature(let_chains)]` to the crate attributes to enable - -error[E0658]: `let` expressions in this position are unstable - --> $DIR/feature-gate.rs:30:24 - | -LL | () if true && (let 0 = 1) => {} - | ^^^^^^^^^ - | - = note: see issue #53667 for more information - = help: add `#![feature(let_chains)]` to the crate attributes to enable - -error[E0658]: `let` expressions in this position are unstable - --> $DIR/feature-gate.rs:34:16 - | -LL | () if (let 0 = 1) && (let 0 = 1) => {} - | ^^^^^^^^^ - | - = note: see issue #53667 for more information - = help: add `#![feature(let_chains)]` to the crate attributes to enable - -error[E0658]: `let` expressions in this position are unstable - --> $DIR/feature-gate.rs:34:31 - | -LL | () if (let 0 = 1) && (let 0 = 1) => {} - | ^^^^^^^^^ - | - = note: see issue #53667 for more information - = help: add `#![feature(let_chains)]` to the crate attributes to enable - -error[E0658]: `let` expressions in this position are unstable - --> $DIR/feature-gate.rs:40:15 + --> $DIR/feature-gate.rs:34:15 | LL | () if let 0 = 1 && let 1 = 2 && (let 2 = 3 && let 3 = 4 && let 4 = 5) => {} | ^^^^^^^^^ @@ -275,7 +221,7 @@ LL | () if let 0 = 1 && let 1 = 2 && (let 2 = 3 && let 3 = 4 && let 4 = = help: add `#![feature(let_chains)]` to the crate attributes to enable error[E0658]: `let` expressions in this position are unstable - --> $DIR/feature-gate.rs:40:28 + --> $DIR/feature-gate.rs:34:28 | LL | () if let 0 = 1 && let 1 = 2 && (let 2 = 3 && let 3 = 4 && let 4 = 5) => {} | ^^^^^^^^^ @@ -284,34 +230,7 @@ LL | () if let 0 = 1 && let 1 = 2 && (let 2 = 3 && let 3 = 4 && let 4 = = help: add `#![feature(let_chains)]` to the crate attributes to enable error[E0658]: `let` expressions in this position are unstable - --> $DIR/feature-gate.rs:40:42 - | -LL | () if let 0 = 1 && let 1 = 2 && (let 2 = 3 && let 3 = 4 && let 4 = 5) => {} - | ^^^^^^^^^ - | - = note: see issue #53667 for more information - = help: add `#![feature(let_chains)]` to the crate attributes to enable - -error[E0658]: `let` expressions in this position are unstable - --> $DIR/feature-gate.rs:40:55 - | -LL | () if let 0 = 1 && let 1 = 2 && (let 2 = 3 && let 3 = 4 && let 4 = 5) => {} - | ^^^^^^^^^ - | - = note: see issue #53667 for more information - = help: add `#![feature(let_chains)]` to the crate attributes to enable - -error[E0658]: `let` expressions in this position are unstable - --> $DIR/feature-gate.rs:40:68 - | -LL | () if let 0 = 1 && let 1 = 2 && (let 2 = 3 && let 3 = 4 && let 4 = 5) => {} - | ^^^^^^^^^ - | - = note: see issue #53667 for more information - = help: add `#![feature(let_chains)]` to the crate attributes to enable - -error[E0658]: `let` expressions in this position are unstable - --> $DIR/feature-gate.rs:52:15 + --> $DIR/feature-gate.rs:43:15 | LL | () if let Range { start: _, end: _ } = (true..true) && false => {} | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ @@ -319,6 +238,6 @@ LL | () if let Range { start: _, end: _ } = (true..true) && false => {} = note: see issue #53667 for more information = help: add `#![feature(let_chains)]` to the crate attributes to enable -error: aborting due to 32 previous errors +error: aborting due to 23 previous errors For more information about this error, try `rustc --explain E0658`. diff --git a/tests/ui/rfcs/rfc-2497-if-let-chains/disallowed-positions-without-feature-gate.rs b/tests/ui/rfcs/rfc-2497-if-let-chains/disallowed-positions-without-feature-gate.rs new file mode 100644 index 00000000000..096036bb133 --- /dev/null +++ b/tests/ui/rfcs/rfc-2497-if-let-chains/disallowed-positions-without-feature-gate.rs @@ -0,0 +1,340 @@ +// Check that we don't suggest enabling a feature for code that's +// not accepted even with that feature. + +#![allow(irrefutable_let_patterns)] + +use std::ops::Range; + +fn main() {} + +fn _if() { + if (let 0 = 1) {} + //~^ ERROR expected expression, found `let` statement + + if (((let 0 = 1))) {} + //~^ ERROR expected expression, found `let` statement + + if (let 0 = 1) && true {} + //~^ ERROR expected expression, found `let` statement + + if true && (let 0 = 1) {} + //~^ ERROR expected expression, found `let` statement + + if (let 0 = 1) && (let 0 = 1) {} + //~^ ERROR expected expression, found `let` statement + //~| ERROR expected expression, found `let` statement + + if (let 2 = 3 && let 3 = 4 && let 4 = 5) {} + //~^ ERROR expected expression, found `let` statement + //~| ERROR expected expression, found `let` statement + //~| ERROR expected expression, found `let` statement +} + +fn _while() { + while (let 0 = 1) {} + //~^ ERROR expected expression, found `let` statement + + while (((let 0 = 1))) {} + //~^ ERROR expected expression, found `let` statement + + while (let 0 = 1) && true {} + //~^ ERROR expected expression, found `let` statement + + while true && (let 0 = 1) {} + //~^ ERROR expected expression, found `let` statement + + while (let 0 = 1) && (let 0 = 1) {} + //~^ ERROR expected expression, found `let` statement + //~| ERROR expected expression, found `let` statement + + while (let 2 = 3 && let 3 = 4 && let 4 = 5) {} + //~^ ERROR expected expression, found `let` statement + //~| ERROR expected expression, found `let` statement + //~| ERROR expected expression, found `let` statement +} + +fn _macros() { + macro_rules! use_expr { + ($e:expr) => { + if $e {} + while $e {} + } + } + use_expr!((let 0 = 1 && 0 == 0)); + //~^ ERROR expected expression, found `let` statement + use_expr!((let 0 = 1)); + //~^ ERROR expected expression, found `let` statement +} + +fn nested_within_if_expr() { + if &let 0 = 0 {} + //~^ ERROR expected expression, found `let` statement + + if !let 0 = 0 {} + //~^ ERROR expected expression, found `let` statement + if *let 0 = 0 {} + //~^ ERROR expected expression, found `let` statement + if -let 0 = 0 {} + //~^ ERROR expected expression, found `let` statement + + fn _check_try_binds_tighter() -> Result<(), ()> { + if let 0 = 0? {} + //~^ ERROR the `?` operator can only be applied to values that implement `Try` + Ok(()) + } + if (let 0 = 0)? {} + //~^ ERROR expected expression, found `let` statement + + if true || let 0 = 0 {} + //~^ ERROR expected expression, found `let` statement + if (true || let 0 = 0) {} + //~^ ERROR expected expression, found `let` statement + if true && (true || let 0 = 0) {} + //~^ ERROR expected expression, found `let` statement + if true || (true && let 0 = 0) {} + //~^ ERROR expected expression, found `let` statement + + let mut x = true; + if x = let 0 = 0 {} + //~^ ERROR expected expression, found `let` statement + + if true..(let 0 = 0) {} + //~^ ERROR expected expression, found `let` statement + //~| ERROR mismatched types + if ..(let 0 = 0) {} + //~^ ERROR expected expression, found `let` statement + if (let 0 = 0).. {} + //~^ ERROR expected expression, found `let` statement + + // Binds as `(let ... = true)..true &&/|| false`. + if let Range { start: _, end: _ } = true..true && false {} + //~^ ERROR expected expression, found `let` statement + //~| ERROR mismatched types + if let Range { start: _, end: _ } = true..true || false {} + //~^ ERROR expected expression, found `let` statement + //~| ERROR mismatched types + + // Binds as `(let Range { start: F, end } = F)..(|| true)`. + const F: fn() -> bool = || true; + if let Range { start: F, end } = F..|| true {} + //~^ ERROR expected expression, found `let` statement + //~| ERROR mismatched types + + // Binds as `(let Range { start: true, end } = t)..(&&false)`. + let t = &&true; + if let Range { start: true, end } = t..&&false {} + //~^ ERROR expected expression, found `let` statement + //~| ERROR mismatched types + + if let true = let true = true {} + //~^ ERROR expected expression, found `let` statement +} + +fn nested_within_while_expr() { + while &let 0 = 0 {} + //~^ ERROR expected expression, found `let` statement + + while !let 0 = 0 {} + //~^ ERROR expected expression, found `let` statement + while *let 0 = 0 {} + //~^ ERROR expected expression, found `let` statement + while -let 0 = 0 {} + //~^ ERROR expected expression, found `let` statement + + fn _check_try_binds_tighter() -> Result<(), ()> { + while let 0 = 0? {} + //~^ ERROR the `?` operator can only be applied to values that implement `Try` + Ok(()) + } + while (let 0 = 0)? {} + //~^ ERROR expected expression, found `let` statement + + while true || let 0 = 0 {} + //~^ ERROR expected expression, found `let` statement + while (true || let 0 = 0) {} + //~^ ERROR expected expression, found `let` statement + while true && (true || let 0 = 0) {} + //~^ ERROR expected expression, found `let` statement + while true || (true && let 0 = 0) {} + //~^ ERROR expected expression, found `let` statement + + let mut x = true; + while x = let 0 = 0 {} + //~^ ERROR expected expression, found `let` statement + + while true..(let 0 = 0) {} + //~^ ERROR expected expression, found `let` statement + //~| ERROR mismatched types + while ..(let 0 = 0) {} + //~^ ERROR expected expression, found `let` statement + while (let 0 = 0).. {} + //~^ ERROR expected expression, found `let` statement + + // Binds as `(let ... = true)..true &&/|| false`. + while let Range { start: _, end: _ } = true..true && false {} + //~^ ERROR expected expression, found `let` statement + //~| ERROR mismatched types + while let Range { start: _, end: _ } = true..true || false {} + //~^ ERROR expected expression, found `let` statement + //~| ERROR mismatched types + + // Binds as `(let Range { start: F, end } = F)..(|| true)`. + const F: fn() -> bool = || true; + while let Range { start: F, end } = F..|| true {} + //~^ ERROR expected expression, found `let` statement + //~| ERROR mismatched types + + // Binds as `(let Range { start: true, end } = t)..(&&false)`. + let t = &&true; + while let Range { start: true, end } = t..&&false {} + //~^ ERROR expected expression, found `let` statement + //~| ERROR mismatched types + + while let true = let true = true {} + //~^ ERROR expected expression, found `let` statement +} + +fn not_error_because_clarified_intent() { + if let Range { start: _, end: _ } = (true..true || false) { } + + if let Range { start: _, end: _ } = (true..true && false) { } + + while let Range { start: _, end: _ } = (true..true || false) { } + + while let Range { start: _, end: _ } = (true..true && false) { } +} + +fn outside_if_and_while_expr() { + &let 0 = 0; + //~^ ERROR expected expression, found `let` statement + + !let 0 = 0; + //~^ ERROR expected expression, found `let` statement + *let 0 = 0; + //~^ ERROR expected expression, found `let` statement + -let 0 = 0; + //~^ ERROR expected expression, found `let` statement + let _ = let _ = 3; + //~^ ERROR expected expression, found `let` statement + + fn _check_try_binds_tighter() -> Result<(), ()> { + let 0 = 0?; + //~^ ERROR the `?` operator can only be applied to values that implement `Try` + Ok(()) + } + (let 0 = 0)?; + //~^ ERROR expected expression, found `let` statement + + true || let 0 = 0; + //~^ ERROR expected expression, found `let` statement + (true || let 0 = 0); + //~^ ERROR expected expression, found `let` statement + true && (true || let 0 = 0); + //~^ ERROR expected expression, found `let` statement + + let mut x = true; + x = let 0 = 0; + //~^ ERROR expected expression, found `let` statement + + true..(let 0 = 0); + //~^ ERROR expected expression, found `let` statement + ..(let 0 = 0); + //~^ ERROR expected expression, found `let` statement + (let 0 = 0)..; + //~^ ERROR expected expression, found `let` statement + + (let Range { start: _, end: _ } = true..true || false); + //~^ ERROR mismatched types + //~| ERROR expected expression, found `let` statement + + (let true = let true = true); + //~^ ERROR expected expression, found `let` statement + //~| ERROR expected expression, found `let` statement + + { + #[cfg(FALSE)] + let x = true && let y = 1; + //~^ ERROR expected expression, found `let` statement + } + + #[cfg(FALSE)] + { + [1, 2, 3][let _ = ()] + //~^ ERROR expected expression, found `let` statement + } + + // Check function tail position. + &let 0 = 0 + //~^ ERROR expected expression, found `let` statement +} + +// Let's make sure that `let` inside const generic arguments are considered. +fn inside_const_generic_arguments() { + struct A; + impl A<{B}> { const O: u32 = 5; } + + if let A::<{ + true && let 1 = 1 + //~^ ERROR expected expression, found `let` statement + }>::O = 5 {} + + while let A::<{ + true && let 1 = 1 + //~^ ERROR expected expression, found `let` statement + }>::O = 5 {} + + if A::<{ + true && let 1 = 1 + //~^ ERROR expected expression, found `let` statement + }>::O == 5 {} + + // In the cases above we have `ExprKind::Block` to help us out. + // Below however, we would not have a block and so an implementation might go + // from visiting expressions to types without banning `let` expressions down the tree. + // This tests ensures that we are not caught by surprise should the parser + // admit non-IDENT expressions in const generic arguments. + + if A::< + true && let 1 = 1 + //~^ ERROR expressions must be enclosed in braces + //~| ERROR expected expression, found `let` statement + >::O == 5 {} +} + +fn with_parenthesis() { + let opt = Some(Some(1i32)); + + if (let Some(a) = opt && true) { + //~^ ERROR expected expression, found `let` statement + } + + if (let Some(a) = opt) && true { + //~^ ERROR expected expression, found `let` statement + } + if (let Some(a) = opt) && (let Some(b) = a) { + //~^ ERROR expected expression, found `let` statement + //~| ERROR expected expression, found `let` statement + } + + if (let Some(a) = opt && (let Some(b) = a)) && b == 1 { + //~^ ERROR expected expression, found `let` statement + //~| ERROR expected expression, found `let` statement + } + if (let Some(a) = opt && (let Some(b) = a)) && true { + //~^ ERROR expected expression, found `let` statement + //~| ERROR expected expression, found `let` statement + } + if (let Some(a) = opt && (true)) && true { + //~^ ERROR expected expression, found `let` statement + } + + #[cfg(FALSE)] + let x = (true && let y = 1); + //~^ ERROR expected expression, found `let` statement + + #[cfg(FALSE)] + { + ([1, 2, 3][let _ = ()]) + //~^ ERROR expected expression, found `let` statement + } +} diff --git a/tests/ui/rfcs/rfc-2497-if-let-chains/disallowed-positions-without-feature-gate.stderr b/tests/ui/rfcs/rfc-2497-if-let-chains/disallowed-positions-without-feature-gate.stderr new file mode 100644 index 00000000000..218ca254d0f --- /dev/null +++ b/tests/ui/rfcs/rfc-2497-if-let-chains/disallowed-positions-without-feature-gate.stderr @@ -0,0 +1,870 @@ +error: expected expression, found `let` statement + --> $DIR/disallowed-positions-without-feature-gate.rs:11:9 + | +LL | if (let 0 = 1) {} + | ^^^^^^^^^ + | +note: `let`s wrapped in parentheses are not supported in a context with let chains + --> $DIR/disallowed-positions-without-feature-gate.rs:11:9 + | +LL | if (let 0 = 1) {} + | ^^^^^^^^^ + +error: expected expression, found `let` statement + --> $DIR/disallowed-positions-without-feature-gate.rs:14:11 + | +LL | if (((let 0 = 1))) {} + | ^^^^^^^^^ + | +note: `let`s wrapped in parentheses are not supported in a context with let chains + --> $DIR/disallowed-positions-without-feature-gate.rs:14:11 + | +LL | if (((let 0 = 1))) {} + | ^^^^^^^^^ + +error: expected expression, found `let` statement + --> $DIR/disallowed-positions-without-feature-gate.rs:17:9 + | +LL | if (let 0 = 1) && true {} + | ^^^^^^^^^ + | +note: `let`s wrapped in parentheses are not supported in a context with let chains + --> $DIR/disallowed-positions-without-feature-gate.rs:17:9 + | +LL | if (let 0 = 1) && true {} + | ^^^^^^^^^ + +error: expected expression, found `let` statement + --> $DIR/disallowed-positions-without-feature-gate.rs:20:17 + | +LL | if true && (let 0 = 1) {} + | ^^^^^^^^^ + | +note: `let`s wrapped in parentheses are not supported in a context with let chains + --> $DIR/disallowed-positions-without-feature-gate.rs:20:17 + | +LL | if true && (let 0 = 1) {} + | ^^^^^^^^^ + +error: expected expression, found `let` statement + --> $DIR/disallowed-positions-without-feature-gate.rs:23:9 + | +LL | if (let 0 = 1) && (let 0 = 1) {} + | ^^^^^^^^^ + | +note: `let`s wrapped in parentheses are not supported in a context with let chains + --> $DIR/disallowed-positions-without-feature-gate.rs:23:9 + | +LL | if (let 0 = 1) && (let 0 = 1) {} + | ^^^^^^^^^ + +error: expected expression, found `let` statement + --> $DIR/disallowed-positions-without-feature-gate.rs:23:24 + | +LL | if (let 0 = 1) && (let 0 = 1) {} + | ^^^^^^^^^ + | +note: `let`s wrapped in parentheses are not supported in a context with let chains + --> $DIR/disallowed-positions-without-feature-gate.rs:23:24 + | +LL | if (let 0 = 1) && (let 0 = 1) {} + | ^^^^^^^^^ + +error: expected expression, found `let` statement + --> $DIR/disallowed-positions-without-feature-gate.rs:27:9 + | +LL | if (let 2 = 3 && let 3 = 4 && let 4 = 5) {} + | ^^^^^^^^^ + | +note: `let`s wrapped in parentheses are not supported in a context with let chains + --> $DIR/disallowed-positions-without-feature-gate.rs:27:9 + | +LL | if (let 2 = 3 && let 3 = 4 && let 4 = 5) {} + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + +error: expected expression, found `let` statement + --> $DIR/disallowed-positions-without-feature-gate.rs:27:22 + | +LL | if (let 2 = 3 && let 3 = 4 && let 4 = 5) {} + | ^^^^^^^^^ + | +note: `let`s wrapped in parentheses are not supported in a context with let chains + --> $DIR/disallowed-positions-without-feature-gate.rs:27:9 + | +LL | if (let 2 = 3 && let 3 = 4 && let 4 = 5) {} + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + +error: expected expression, found `let` statement + --> $DIR/disallowed-positions-without-feature-gate.rs:27:35 + | +LL | if (let 2 = 3 && let 3 = 4 && let 4 = 5) {} + | ^^^^^^^^^ + | +note: `let`s wrapped in parentheses are not supported in a context with let chains + --> $DIR/disallowed-positions-without-feature-gate.rs:27:9 + | +LL | if (let 2 = 3 && let 3 = 4 && let 4 = 5) {} + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + +error: expected expression, found `let` statement + --> $DIR/disallowed-positions-without-feature-gate.rs:34:12 + | +LL | while (let 0 = 1) {} + | ^^^^^^^^^ + | +note: `let`s wrapped in parentheses are not supported in a context with let chains + --> $DIR/disallowed-positions-without-feature-gate.rs:34:12 + | +LL | while (let 0 = 1) {} + | ^^^^^^^^^ + +error: expected expression, found `let` statement + --> $DIR/disallowed-positions-without-feature-gate.rs:37:14 + | +LL | while (((let 0 = 1))) {} + | ^^^^^^^^^ + | +note: `let`s wrapped in parentheses are not supported in a context with let chains + --> $DIR/disallowed-positions-without-feature-gate.rs:37:14 + | +LL | while (((let 0 = 1))) {} + | ^^^^^^^^^ + +error: expected expression, found `let` statement + --> $DIR/disallowed-positions-without-feature-gate.rs:40:12 + | +LL | while (let 0 = 1) && true {} + | ^^^^^^^^^ + | +note: `let`s wrapped in parentheses are not supported in a context with let chains + --> $DIR/disallowed-positions-without-feature-gate.rs:40:12 + | +LL | while (let 0 = 1) && true {} + | ^^^^^^^^^ + +error: expected expression, found `let` statement + --> $DIR/disallowed-positions-without-feature-gate.rs:43:20 + | +LL | while true && (let 0 = 1) {} + | ^^^^^^^^^ + | +note: `let`s wrapped in parentheses are not supported in a context with let chains + --> $DIR/disallowed-positions-without-feature-gate.rs:43:20 + | +LL | while true && (let 0 = 1) {} + | ^^^^^^^^^ + +error: expected expression, found `let` statement + --> $DIR/disallowed-positions-without-feature-gate.rs:46:12 + | +LL | while (let 0 = 1) && (let 0 = 1) {} + | ^^^^^^^^^ + | +note: `let`s wrapped in parentheses are not supported in a context with let chains + --> $DIR/disallowed-positions-without-feature-gate.rs:46:12 + | +LL | while (let 0 = 1) && (let 0 = 1) {} + | ^^^^^^^^^ + +error: expected expression, found `let` statement + --> $DIR/disallowed-positions-without-feature-gate.rs:46:27 + | +LL | while (let 0 = 1) && (let 0 = 1) {} + | ^^^^^^^^^ + | +note: `let`s wrapped in parentheses are not supported in a context with let chains + --> $DIR/disallowed-positions-without-feature-gate.rs:46:27 + | +LL | while (let 0 = 1) && (let 0 = 1) {} + | ^^^^^^^^^ + +error: expected expression, found `let` statement + --> $DIR/disallowed-positions-without-feature-gate.rs:50:12 + | +LL | while (let 2 = 3 && let 3 = 4 && let 4 = 5) {} + | ^^^^^^^^^ + | +note: `let`s wrapped in parentheses are not supported in a context with let chains + --> $DIR/disallowed-positions-without-feature-gate.rs:50:12 + | +LL | while (let 2 = 3 && let 3 = 4 && let 4 = 5) {} + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + +error: expected expression, found `let` statement + --> $DIR/disallowed-positions-without-feature-gate.rs:50:25 + | +LL | while (let 2 = 3 && let 3 = 4 && let 4 = 5) {} + | ^^^^^^^^^ + | +note: `let`s wrapped in parentheses are not supported in a context with let chains + --> $DIR/disallowed-positions-without-feature-gate.rs:50:12 + | +LL | while (let 2 = 3 && let 3 = 4 && let 4 = 5) {} + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + +error: expected expression, found `let` statement + --> $DIR/disallowed-positions-without-feature-gate.rs:50:38 + | +LL | while (let 2 = 3 && let 3 = 4 && let 4 = 5) {} + | ^^^^^^^^^ + | +note: `let`s wrapped in parentheses are not supported in a context with let chains + --> $DIR/disallowed-positions-without-feature-gate.rs:50:12 + | +LL | while (let 2 = 3 && let 3 = 4 && let 4 = 5) {} + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + +error: expected expression, found `let` statement + --> $DIR/disallowed-positions-without-feature-gate.rs:70:9 + | +LL | if &let 0 = 0 {} + | ^^^^^^^^^ + +error: expected expression, found `let` statement + --> $DIR/disallowed-positions-without-feature-gate.rs:73:9 + | +LL | if !let 0 = 0 {} + | ^^^^^^^^^ + +error: expected expression, found `let` statement + --> $DIR/disallowed-positions-without-feature-gate.rs:75:9 + | +LL | if *let 0 = 0 {} + | ^^^^^^^^^ + +error: expected expression, found `let` statement + --> $DIR/disallowed-positions-without-feature-gate.rs:77:9 + | +LL | if -let 0 = 0 {} + | ^^^^^^^^^ + +error: expected expression, found `let` statement + --> $DIR/disallowed-positions-without-feature-gate.rs:85:9 + | +LL | if (let 0 = 0)? {} + | ^^^^^^^^^ + +error: expected expression, found `let` statement + --> $DIR/disallowed-positions-without-feature-gate.rs:88:16 + | +LL | if true || let 0 = 0 {} + | ^^^^^^^^^ + | +note: `||` operators are not supported in let chain expressions + --> $DIR/disallowed-positions-without-feature-gate.rs:88:13 + | +LL | if true || let 0 = 0 {} + | ^^ + +error: expected expression, found `let` statement + --> $DIR/disallowed-positions-without-feature-gate.rs:90:17 + | +LL | if (true || let 0 = 0) {} + | ^^^^^^^^^ + +error: expected expression, found `let` statement + --> $DIR/disallowed-positions-without-feature-gate.rs:92:25 + | +LL | if true && (true || let 0 = 0) {} + | ^^^^^^^^^ + +error: expected expression, found `let` statement + --> $DIR/disallowed-positions-without-feature-gate.rs:94:25 + | +LL | if true || (true && let 0 = 0) {} + | ^^^^^^^^^ + +error: expected expression, found `let` statement + --> $DIR/disallowed-positions-without-feature-gate.rs:98:12 + | +LL | if x = let 0 = 0 {} + | ^^^ + +error: expected expression, found `let` statement + --> $DIR/disallowed-positions-without-feature-gate.rs:101:15 + | +LL | if true..(let 0 = 0) {} + | ^^^^^^^^^ + +error: expected expression, found `let` statement + --> $DIR/disallowed-positions-without-feature-gate.rs:104:11 + | +LL | if ..(let 0 = 0) {} + | ^^^^^^^^^ + +error: expected expression, found `let` statement + --> $DIR/disallowed-positions-without-feature-gate.rs:106:9 + | +LL | if (let 0 = 0).. {} + | ^^^^^^^^^ + +error: expected expression, found `let` statement + --> $DIR/disallowed-positions-without-feature-gate.rs:110:8 + | +LL | if let Range { start: _, end: _ } = true..true && false {} + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + +error: expected expression, found `let` statement + --> $DIR/disallowed-positions-without-feature-gate.rs:113:8 + | +LL | if let Range { start: _, end: _ } = true..true || false {} + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + +error: expected expression, found `let` statement + --> $DIR/disallowed-positions-without-feature-gate.rs:119:8 + | +LL | if let Range { start: F, end } = F..|| true {} + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + +error: expected expression, found `let` statement + --> $DIR/disallowed-positions-without-feature-gate.rs:125:8 + | +LL | if let Range { start: true, end } = t..&&false {} + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + +error: expected expression, found `let` statement + --> $DIR/disallowed-positions-without-feature-gate.rs:129:19 + | +LL | if let true = let true = true {} + | ^^^ + +error: expected expression, found `let` statement + --> $DIR/disallowed-positions-without-feature-gate.rs:134:12 + | +LL | while &let 0 = 0 {} + | ^^^^^^^^^ + +error: expected expression, found `let` statement + --> $DIR/disallowed-positions-without-feature-gate.rs:137:12 + | +LL | while !let 0 = 0 {} + | ^^^^^^^^^ + +error: expected expression, found `let` statement + --> $DIR/disallowed-positions-without-feature-gate.rs:139:12 + | +LL | while *let 0 = 0 {} + | ^^^^^^^^^ + +error: expected expression, found `let` statement + --> $DIR/disallowed-positions-without-feature-gate.rs:141:12 + | +LL | while -let 0 = 0 {} + | ^^^^^^^^^ + +error: expected expression, found `let` statement + --> $DIR/disallowed-positions-without-feature-gate.rs:149:12 + | +LL | while (let 0 = 0)? {} + | ^^^^^^^^^ + +error: expected expression, found `let` statement + --> $DIR/disallowed-positions-without-feature-gate.rs:152:19 + | +LL | while true || let 0 = 0 {} + | ^^^^^^^^^ + | +note: `||` operators are not supported in let chain expressions + --> $DIR/disallowed-positions-without-feature-gate.rs:152:16 + | +LL | while true || let 0 = 0 {} + | ^^ + +error: expected expression, found `let` statement + --> $DIR/disallowed-positions-without-feature-gate.rs:154:20 + | +LL | while (true || let 0 = 0) {} + | ^^^^^^^^^ + +error: expected expression, found `let` statement + --> $DIR/disallowed-positions-without-feature-gate.rs:156:28 + | +LL | while true && (true || let 0 = 0) {} + | ^^^^^^^^^ + +error: expected expression, found `let` statement + --> $DIR/disallowed-positions-without-feature-gate.rs:158:28 + | +LL | while true || (true && let 0 = 0) {} + | ^^^^^^^^^ + +error: expected expression, found `let` statement + --> $DIR/disallowed-positions-without-feature-gate.rs:162:15 + | +LL | while x = let 0 = 0 {} + | ^^^ + +error: expected expression, found `let` statement + --> $DIR/disallowed-positions-without-feature-gate.rs:165:18 + | +LL | while true..(let 0 = 0) {} + | ^^^^^^^^^ + +error: expected expression, found `let` statement + --> $DIR/disallowed-positions-without-feature-gate.rs:168:14 + | +LL | while ..(let 0 = 0) {} + | ^^^^^^^^^ + +error: expected expression, found `let` statement + --> $DIR/disallowed-positions-without-feature-gate.rs:170:12 + | +LL | while (let 0 = 0).. {} + | ^^^^^^^^^ + +error: expected expression, found `let` statement + --> $DIR/disallowed-positions-without-feature-gate.rs:174:11 + | +LL | while let Range { start: _, end: _ } = true..true && false {} + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + +error: expected expression, found `let` statement + --> $DIR/disallowed-positions-without-feature-gate.rs:177:11 + | +LL | while let Range { start: _, end: _ } = true..true || false {} + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + +error: expected expression, found `let` statement + --> $DIR/disallowed-positions-without-feature-gate.rs:183:11 + | +LL | while let Range { start: F, end } = F..|| true {} + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + +error: expected expression, found `let` statement + --> $DIR/disallowed-positions-without-feature-gate.rs:189:11 + | +LL | while let Range { start: true, end } = t..&&false {} + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + +error: expected expression, found `let` statement + --> $DIR/disallowed-positions-without-feature-gate.rs:193:22 + | +LL | while let true = let true = true {} + | ^^^ + +error: expected expression, found `let` statement + --> $DIR/disallowed-positions-without-feature-gate.rs:208:6 + | +LL | &let 0 = 0; + | ^^^ + +error: expected expression, found `let` statement + --> $DIR/disallowed-positions-without-feature-gate.rs:211:6 + | +LL | !let 0 = 0; + | ^^^ + +error: expected expression, found `let` statement + --> $DIR/disallowed-positions-without-feature-gate.rs:213:6 + | +LL | *let 0 = 0; + | ^^^ + +error: expected expression, found `let` statement + --> $DIR/disallowed-positions-without-feature-gate.rs:215:6 + | +LL | -let 0 = 0; + | ^^^ + +error: expected expression, found `let` statement + --> $DIR/disallowed-positions-without-feature-gate.rs:217:13 + | +LL | let _ = let _ = 3; + | ^^^ + +error: expected expression, found `let` statement + --> $DIR/disallowed-positions-without-feature-gate.rs:225:6 + | +LL | (let 0 = 0)?; + | ^^^ + +error: expected expression, found `let` statement + --> $DIR/disallowed-positions-without-feature-gate.rs:228:13 + | +LL | true || let 0 = 0; + | ^^^ + +error: expected expression, found `let` statement + --> $DIR/disallowed-positions-without-feature-gate.rs:230:14 + | +LL | (true || let 0 = 0); + | ^^^ + +error: expected expression, found `let` statement + --> $DIR/disallowed-positions-without-feature-gate.rs:232:22 + | +LL | true && (true || let 0 = 0); + | ^^^ + +error: expected expression, found `let` statement + --> $DIR/disallowed-positions-without-feature-gate.rs:236:9 + | +LL | x = let 0 = 0; + | ^^^ + +error: expected expression, found `let` statement + --> $DIR/disallowed-positions-without-feature-gate.rs:239:12 + | +LL | true..(let 0 = 0); + | ^^^ + +error: expected expression, found `let` statement + --> $DIR/disallowed-positions-without-feature-gate.rs:241:8 + | +LL | ..(let 0 = 0); + | ^^^ + +error: expected expression, found `let` statement + --> $DIR/disallowed-positions-without-feature-gate.rs:243:6 + | +LL | (let 0 = 0)..; + | ^^^ + +error: expected expression, found `let` statement + --> $DIR/disallowed-positions-without-feature-gate.rs:246:6 + | +LL | (let Range { start: _, end: _ } = true..true || false); + | ^^^ + +error: expected expression, found `let` statement + --> $DIR/disallowed-positions-without-feature-gate.rs:250:6 + | +LL | (let true = let true = true); + | ^^^ + +error: expected expression, found `let` statement + --> $DIR/disallowed-positions-without-feature-gate.rs:250:17 + | +LL | (let true = let true = true); + | ^^^ + +error: expected expression, found `let` statement + --> $DIR/disallowed-positions-without-feature-gate.rs:256:25 + | +LL | let x = true && let y = 1; + | ^^^ + +error: expected expression, found `let` statement + --> $DIR/disallowed-positions-without-feature-gate.rs:262:19 + | +LL | [1, 2, 3][let _ = ()] + | ^^^ + +error: expected expression, found `let` statement + --> $DIR/disallowed-positions-without-feature-gate.rs:267:6 + | +LL | &let 0 = 0 + | ^^^ + +error: expected expression, found `let` statement + --> $DIR/disallowed-positions-without-feature-gate.rs:277:17 + | +LL | true && let 1 = 1 + | ^^^ + +error: expected expression, found `let` statement + --> $DIR/disallowed-positions-without-feature-gate.rs:282:17 + | +LL | true && let 1 = 1 + | ^^^ + +error: expected expression, found `let` statement + --> $DIR/disallowed-positions-without-feature-gate.rs:287:17 + | +LL | true && let 1 = 1 + | ^^^ + +error: expected expression, found `let` statement + --> $DIR/disallowed-positions-without-feature-gate.rs:298:17 + | +LL | true && let 1 = 1 + | ^^^ + +error: expressions must be enclosed in braces to be used as const generic arguments + --> $DIR/disallowed-positions-without-feature-gate.rs:298:9 + | +LL | true && let 1 = 1 + | ^^^^^^^^^^^^^^^^^ + | +help: enclose the `const` expression in braces + | +LL | { true && let 1 = 1 } + | + + + +error: expected expression, found `let` statement + --> $DIR/disallowed-positions-without-feature-gate.rs:307:9 + | +LL | if (let Some(a) = opt && true) { + | ^^^^^^^^^^^^^^^^^ + | +note: `let`s wrapped in parentheses are not supported in a context with let chains + --> $DIR/disallowed-positions-without-feature-gate.rs:307:9 + | +LL | if (let Some(a) = opt && true) { + | ^^^^^^^^^^^^^^^^^^^^^^^^^ + +error: expected expression, found `let` statement + --> $DIR/disallowed-positions-without-feature-gate.rs:311:9 + | +LL | if (let Some(a) = opt) && true { + | ^^^^^^^^^^^^^^^^^ + | +note: `let`s wrapped in parentheses are not supported in a context with let chains + --> $DIR/disallowed-positions-without-feature-gate.rs:311:9 + | +LL | if (let Some(a) = opt) && true { + | ^^^^^^^^^^^^^^^^^ + +error: expected expression, found `let` statement + --> $DIR/disallowed-positions-without-feature-gate.rs:314:9 + | +LL | if (let Some(a) = opt) && (let Some(b) = a) { + | ^^^^^^^^^^^^^^^^^ + | +note: `let`s wrapped in parentheses are not supported in a context with let chains + --> $DIR/disallowed-positions-without-feature-gate.rs:314:9 + | +LL | if (let Some(a) = opt) && (let Some(b) = a) { + | ^^^^^^^^^^^^^^^^^ + +error: expected expression, found `let` statement + --> $DIR/disallowed-positions-without-feature-gate.rs:314:32 + | +LL | if (let Some(a) = opt) && (let Some(b) = a) { + | ^^^^^^^^^^^^^^^ + | +note: `let`s wrapped in parentheses are not supported in a context with let chains + --> $DIR/disallowed-positions-without-feature-gate.rs:314:32 + | +LL | if (let Some(a) = opt) && (let Some(b) = a) { + | ^^^^^^^^^^^^^^^ + +error: expected expression, found `let` statement + --> $DIR/disallowed-positions-without-feature-gate.rs:319:9 + | +LL | if (let Some(a) = opt && (let Some(b) = a)) && b == 1 { + | ^^^^^^^^^^^^^^^^^ + | +note: `let`s wrapped in parentheses are not supported in a context with let chains + --> $DIR/disallowed-positions-without-feature-gate.rs:319:9 + | +LL | if (let Some(a) = opt && (let Some(b) = a)) && b == 1 { + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + +error: expected expression, found `let` statement + --> $DIR/disallowed-positions-without-feature-gate.rs:319:31 + | +LL | if (let Some(a) = opt && (let Some(b) = a)) && b == 1 { + | ^^^^^^^^^^^^^^^ + | +note: `let`s wrapped in parentheses are not supported in a context with let chains + --> $DIR/disallowed-positions-without-feature-gate.rs:319:31 + | +LL | if (let Some(a) = opt && (let Some(b) = a)) && b == 1 { + | ^^^^^^^^^^^^^^^ + +error: expected expression, found `let` statement + --> $DIR/disallowed-positions-without-feature-gate.rs:323:9 + | +LL | if (let Some(a) = opt && (let Some(b) = a)) && true { + | ^^^^^^^^^^^^^^^^^ + | +note: `let`s wrapped in parentheses are not supported in a context with let chains + --> $DIR/disallowed-positions-without-feature-gate.rs:323:9 + | +LL | if (let Some(a) = opt && (let Some(b) = a)) && true { + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + +error: expected expression, found `let` statement + --> $DIR/disallowed-positions-without-feature-gate.rs:323:31 + | +LL | if (let Some(a) = opt && (let Some(b) = a)) && true { + | ^^^^^^^^^^^^^^^ + | +note: `let`s wrapped in parentheses are not supported in a context with let chains + --> $DIR/disallowed-positions-without-feature-gate.rs:323:31 + | +LL | if (let Some(a) = opt && (let Some(b) = a)) && true { + | ^^^^^^^^^^^^^^^ + +error: expected expression, found `let` statement + --> $DIR/disallowed-positions-without-feature-gate.rs:327:9 + | +LL | if (let Some(a) = opt && (true)) && true { + | ^^^^^^^^^^^^^^^^^ + | +note: `let`s wrapped in parentheses are not supported in a context with let chains + --> $DIR/disallowed-positions-without-feature-gate.rs:327:9 + | +LL | if (let Some(a) = opt && (true)) && true { + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^ + +error: expected expression, found `let` statement + --> $DIR/disallowed-positions-without-feature-gate.rs:332:22 + | +LL | let x = (true && let y = 1); + | ^^^ + +error: expected expression, found `let` statement + --> $DIR/disallowed-positions-without-feature-gate.rs:337:20 + | +LL | ([1, 2, 3][let _ = ()]) + | ^^^ + +error: expected expression, found `let` statement + --> $DIR/disallowed-positions-without-feature-gate.rs:63:16 + | +LL | use_expr!((let 0 = 1 && 0 == 0)); + | ^^^ + +error: expected expression, found `let` statement + --> $DIR/disallowed-positions-without-feature-gate.rs:65:16 + | +LL | use_expr!((let 0 = 1)); + | ^^^ + +error[E0308]: mismatched types + --> $DIR/disallowed-positions-without-feature-gate.rs:101:8 + | +LL | if true..(let 0 = 0) {} + | ^^^^^^^^^^^^^^^^^ expected `bool`, found `Range` + | + = note: expected type `bool` + found struct `std::ops::Range` + +error[E0308]: mismatched types + --> $DIR/disallowed-positions-without-feature-gate.rs:110:12 + | +LL | if let Range { start: _, end: _ } = true..true && false {} + | ^^^^^^^^^^^^^^^^^^^^^^^^^^ ---- this expression has type `bool` + | | + | expected `bool`, found `Range<_>` + | + = note: expected type `bool` + found struct `std::ops::Range<_>` + +error[E0308]: mismatched types + --> $DIR/disallowed-positions-without-feature-gate.rs:113:12 + | +LL | if let Range { start: _, end: _ } = true..true || false {} + | ^^^^^^^^^^^^^^^^^^^^^^^^^^ ---- this expression has type `bool` + | | + | expected `bool`, found `Range<_>` + | + = note: expected type `bool` + found struct `std::ops::Range<_>` + +error[E0308]: mismatched types + --> $DIR/disallowed-positions-without-feature-gate.rs:119:12 + | +LL | if let Range { start: F, end } = F..|| true {} + | ^^^^^^^^^^^^^^^^^^^^^^^ - this expression has type `fn() -> bool` + | | + | expected fn pointer, found `Range<_>` + | + = note: expected fn pointer `fn() -> bool` + found struct `std::ops::Range<_>` + +error[E0308]: mismatched types + --> $DIR/disallowed-positions-without-feature-gate.rs:125:12 + | +LL | if let Range { start: true, end } = t..&&false {} + | ^^^^^^^^^^^^^^^^^^^^^^^^^^ - this expression has type `&&bool` + | | + | expected `bool`, found `Range<_>` + | + = note: expected type `bool` + found struct `std::ops::Range<_>` + +error[E0277]: the `?` operator can only be applied to values that implement `Try` + --> $DIR/disallowed-positions-without-feature-gate.rs:81:20 + | +LL | if let 0 = 0? {} + | ^^ the `?` operator cannot be applied to type `{integer}` + | + = help: the trait `Try` is not implemented for `{integer}` + +error[E0308]: mismatched types + --> $DIR/disallowed-positions-without-feature-gate.rs:165:11 + | +LL | while true..(let 0 = 0) {} + | ^^^^^^^^^^^^^^^^^ expected `bool`, found `Range` + | + = note: expected type `bool` + found struct `std::ops::Range` + +error[E0308]: mismatched types + --> $DIR/disallowed-positions-without-feature-gate.rs:174:15 + | +LL | while let Range { start: _, end: _ } = true..true && false {} + | ^^^^^^^^^^^^^^^^^^^^^^^^^^ ---- this expression has type `bool` + | | + | expected `bool`, found `Range<_>` + | + = note: expected type `bool` + found struct `std::ops::Range<_>` + +error[E0308]: mismatched types + --> $DIR/disallowed-positions-without-feature-gate.rs:177:15 + | +LL | while let Range { start: _, end: _ } = true..true || false {} + | ^^^^^^^^^^^^^^^^^^^^^^^^^^ ---- this expression has type `bool` + | | + | expected `bool`, found `Range<_>` + | + = note: expected type `bool` + found struct `std::ops::Range<_>` + +error[E0308]: mismatched types + --> $DIR/disallowed-positions-without-feature-gate.rs:183:15 + | +LL | while let Range { start: F, end } = F..|| true {} + | ^^^^^^^^^^^^^^^^^^^^^^^ - this expression has type `fn() -> bool` + | | + | expected fn pointer, found `Range<_>` + | + = note: expected fn pointer `fn() -> bool` + found struct `std::ops::Range<_>` + +error[E0308]: mismatched types + --> $DIR/disallowed-positions-without-feature-gate.rs:189:15 + | +LL | while let Range { start: true, end } = t..&&false {} + | ^^^^^^^^^^^^^^^^^^^^^^^^^^ - this expression has type `&&bool` + | | + | expected `bool`, found `Range<_>` + | + = note: expected type `bool` + found struct `std::ops::Range<_>` + +error[E0277]: the `?` operator can only be applied to values that implement `Try` + --> $DIR/disallowed-positions-without-feature-gate.rs:145:23 + | +LL | while let 0 = 0? {} + | ^^ the `?` operator cannot be applied to type `{integer}` + | + = help: the trait `Try` is not implemented for `{integer}` + +error[E0308]: mismatched types + --> $DIR/disallowed-positions-without-feature-gate.rs:246:10 + | +LL | (let Range { start: _, end: _ } = true..true || false); + | ^^^^^^^^^^^^^^^^^^^^^^^^^^ ---- this expression has type `bool` + | | + | expected `bool`, found `Range<_>` + | + = note: expected type `bool` + found struct `std::ops::Range<_>` + +error[E0277]: the `?` operator can only be applied to values that implement `Try` + --> $DIR/disallowed-positions-without-feature-gate.rs:221:17 + | +LL | let 0 = 0?; + | ^^ the `?` operator cannot be applied to type `{integer}` + | + = help: the trait `Try` is not implemented for `{integer}` + +error: aborting due to 105 previous errors + +Some errors have detailed explanations: E0277, E0308. +For more information about an error, try `rustc --explain E0277`.