From d3c3c17abb3a4cb38be0fec3ea2cb62bdd452e06 Mon Sep 17 00:00:00 2001 From: Matthew Jasper Date: Thu, 24 Aug 2023 09:41:30 +0100 Subject: [PATCH] Add more tests for if_let_guard --- .../rfcs/rfc-2294-if-let-guard/exhaustive.rs | 18 +++++++ .../rfc-2294-if-let-guard/exhaustive.stderr | 35 +++++++++++++ .../rfc-2294-if-let-guard/guard-lifetime-1.rs | 15 ++++++ .../guard-lifetime-1.stderr | 15 ++++++ .../rfc-2294-if-let-guard/guard-lifetime-2.rs | 16 ++++++ .../guard-mutability-1.rs | 14 +++++ .../guard-mutability-1.stderr | 11 ++++ .../guard-mutability-2.rs | 14 +++++ .../guard-mutability-2.stderr | 11 ++++ .../rfc-2294-if-let-guard/macro-expanded.rs | 16 ++++++ .../macro-expanded.stderr | 13 +++++ tests/ui/rfcs/rfc-2294-if-let-guard/parens.rs | 27 ++++++++++ .../rfcs/rfc-2294-if-let-guard/parens.stderr | 52 +++++++++++++++++++ .../partially-macro-expanded.rs | 18 +++++++ .../rfcs/rfc-2294-if-let-guard/shadowing.rs | 23 ++++++++ 15 files changed, 298 insertions(+) create mode 100644 tests/ui/rfcs/rfc-2294-if-let-guard/exhaustive.rs create mode 100644 tests/ui/rfcs/rfc-2294-if-let-guard/exhaustive.stderr create mode 100644 tests/ui/rfcs/rfc-2294-if-let-guard/guard-lifetime-1.rs create mode 100644 tests/ui/rfcs/rfc-2294-if-let-guard/guard-lifetime-1.stderr create mode 100644 tests/ui/rfcs/rfc-2294-if-let-guard/guard-lifetime-2.rs create mode 100644 tests/ui/rfcs/rfc-2294-if-let-guard/guard-mutability-1.rs create mode 100644 tests/ui/rfcs/rfc-2294-if-let-guard/guard-mutability-1.stderr create mode 100644 tests/ui/rfcs/rfc-2294-if-let-guard/guard-mutability-2.rs create mode 100644 tests/ui/rfcs/rfc-2294-if-let-guard/guard-mutability-2.stderr create mode 100644 tests/ui/rfcs/rfc-2294-if-let-guard/macro-expanded.rs create mode 100644 tests/ui/rfcs/rfc-2294-if-let-guard/macro-expanded.stderr create mode 100644 tests/ui/rfcs/rfc-2294-if-let-guard/parens.rs create mode 100644 tests/ui/rfcs/rfc-2294-if-let-guard/parens.stderr create mode 100644 tests/ui/rfcs/rfc-2294-if-let-guard/partially-macro-expanded.rs create mode 100644 tests/ui/rfcs/rfc-2294-if-let-guard/shadowing.rs diff --git a/tests/ui/rfcs/rfc-2294-if-let-guard/exhaustive.rs b/tests/ui/rfcs/rfc-2294-if-let-guard/exhaustive.rs new file mode 100644 index 00000000000..b4eb541398c --- /dev/null +++ b/tests/ui/rfcs/rfc-2294-if-let-guard/exhaustive.rs @@ -0,0 +1,18 @@ +#![feature(if_let_guard)] +#![allow(irrefutable_let_patterns)] + +fn match_option(x: Option) { + match x { + //~^ ERROR non-exhaustive patterns: `None` not covered + Some(_) => {} + None if let y = x => {} + } +} + +fn main() { + let x = (); + match x { + //~^ ERROR non-exhaustive patterns: `()` not covered + y if let z = y => {} + } +} diff --git a/tests/ui/rfcs/rfc-2294-if-let-guard/exhaustive.stderr b/tests/ui/rfcs/rfc-2294-if-let-guard/exhaustive.stderr new file mode 100644 index 00000000000..ddd08854ff7 --- /dev/null +++ b/tests/ui/rfcs/rfc-2294-if-let-guard/exhaustive.stderr @@ -0,0 +1,35 @@ +error[E0004]: non-exhaustive patterns: `None` not covered + --> $DIR/exhaustive.rs:5:11 + | +LL | match x { + | ^ pattern `None` not covered + | +note: `Option` defined here + --> $SRC_DIR/core/src/option.rs:LL:COL + ::: $SRC_DIR/core/src/option.rs:LL:COL + | + = note: not covered + = note: the matched value is of type `Option` +help: ensure that all possible cases are being handled by adding a match arm with a wildcard pattern or an explicit pattern as shown + | +LL ~ None if let y = x => {}, +LL + None => todo!() + | + +error[E0004]: non-exhaustive patterns: `()` not covered + --> $DIR/exhaustive.rs:14:11 + | +LL | match x { + | ^ pattern `()` not covered + | + = note: the matched value is of type `()` + = note: match arms with guards don't count towards exhaustivity +help: ensure that all possible cases are being handled by adding a match arm with a wildcard pattern or an explicit pattern as shown + | +LL ~ y if let z = y => {}, +LL + () => todo!() + | + +error: aborting due to 2 previous errors + +For more information about this error, try `rustc --explain E0004`. diff --git a/tests/ui/rfcs/rfc-2294-if-let-guard/guard-lifetime-1.rs b/tests/ui/rfcs/rfc-2294-if-let-guard/guard-lifetime-1.rs new file mode 100644 index 00000000000..792225e656f --- /dev/null +++ b/tests/ui/rfcs/rfc-2294-if-let-guard/guard-lifetime-1.rs @@ -0,0 +1,15 @@ +// References to by-move bindings in an if-let guard *cannot* be used after the guard. + +#![feature(if_let_guard)] + +fn main() { + let x: Option> = Some(Some(String::new())); + match x { + Some(mut y) if let Some(ref z) = y => { + //~^ ERROR: cannot move out of `x.0` because it is borrowed + let _z: &String = z; + let _y: Option = y; + } + _ => {} + } +} diff --git a/tests/ui/rfcs/rfc-2294-if-let-guard/guard-lifetime-1.stderr b/tests/ui/rfcs/rfc-2294-if-let-guard/guard-lifetime-1.stderr new file mode 100644 index 00000000000..b8e1bb324b1 --- /dev/null +++ b/tests/ui/rfcs/rfc-2294-if-let-guard/guard-lifetime-1.stderr @@ -0,0 +1,15 @@ +error[E0505]: cannot move out of `x.0` because it is borrowed + --> $DIR/guard-lifetime-1.rs:8:14 + | +LL | Some(mut y) if let Some(ref z) = y => { + | ^^^^^ + | | + | move out of `x.0` occurs here + | borrow of `x.0` occurs here +LL | +LL | let _z: &String = z; + | - borrow later used here + +error: aborting due to previous error + +For more information about this error, try `rustc --explain E0505`. diff --git a/tests/ui/rfcs/rfc-2294-if-let-guard/guard-lifetime-2.rs b/tests/ui/rfcs/rfc-2294-if-let-guard/guard-lifetime-2.rs new file mode 100644 index 00000000000..aa2154e3e9e --- /dev/null +++ b/tests/ui/rfcs/rfc-2294-if-let-guard/guard-lifetime-2.rs @@ -0,0 +1,16 @@ +// References to by-mutable-ref bindings in an if-let guard *can* be used after the guard. + +// check-pass + +#![feature(if_let_guard)] + +fn main() { + let mut x: Option> = Some(Some(String::new())); + match x { + Some(ref mut y) if let Some(ref z) = *y => { + let _z: &String = z; + let _y: &mut Option = y; + } + _ => {} + } +} diff --git a/tests/ui/rfcs/rfc-2294-if-let-guard/guard-mutability-1.rs b/tests/ui/rfcs/rfc-2294-if-let-guard/guard-mutability-1.rs new file mode 100644 index 00000000000..9353c9d92f8 --- /dev/null +++ b/tests/ui/rfcs/rfc-2294-if-let-guard/guard-mutability-1.rs @@ -0,0 +1,14 @@ +// Check mutable bindings cannot be mutated by an if-let guard. + +#![feature(if_let_guard)] + +fn main() { + let x: Option> = Some(Some(6)); + match x { + Some(mut y) if let Some(ref mut z) = y => { + //~^ ERROR cannot borrow `y.0` as mutable, as it is immutable for the pattern guard + let _: &mut i32 = z; + } + _ => {} + } +} diff --git a/tests/ui/rfcs/rfc-2294-if-let-guard/guard-mutability-1.stderr b/tests/ui/rfcs/rfc-2294-if-let-guard/guard-mutability-1.stderr new file mode 100644 index 00000000000..009d153387e --- /dev/null +++ b/tests/ui/rfcs/rfc-2294-if-let-guard/guard-mutability-1.stderr @@ -0,0 +1,11 @@ +error[E0596]: cannot borrow `y.0` as mutable, as it is immutable for the pattern guard + --> $DIR/guard-mutability-1.rs:8:33 + | +LL | Some(mut y) if let Some(ref mut z) = y => { + | ^^^^^^^^^ cannot borrow as mutable + | + = note: variables bound in patterns are immutable until the end of the pattern guard + +error: aborting due to previous error + +For more information about this error, try `rustc --explain E0596`. diff --git a/tests/ui/rfcs/rfc-2294-if-let-guard/guard-mutability-2.rs b/tests/ui/rfcs/rfc-2294-if-let-guard/guard-mutability-2.rs new file mode 100644 index 00000000000..4efa02f57a6 --- /dev/null +++ b/tests/ui/rfcs/rfc-2294-if-let-guard/guard-mutability-2.rs @@ -0,0 +1,14 @@ +// Check mutable reference bindings cannot be mutated by an if-let guard. + +#![feature(if_let_guard)] + +fn main() { + let mut x: Option> = Some(Some(6)); + match x { + Some(ref mut y) if let Some(ref mut z) = *y => { + //~^ ERROR cannot borrow `y.0` as mutable, as it is immutable for the pattern guard + let _: &mut i32 = z; + } + _ => {} + } +} diff --git a/tests/ui/rfcs/rfc-2294-if-let-guard/guard-mutability-2.stderr b/tests/ui/rfcs/rfc-2294-if-let-guard/guard-mutability-2.stderr new file mode 100644 index 00000000000..07e7c6a2c07 --- /dev/null +++ b/tests/ui/rfcs/rfc-2294-if-let-guard/guard-mutability-2.stderr @@ -0,0 +1,11 @@ +error[E0596]: cannot borrow `y.0` as mutable, as it is immutable for the pattern guard + --> $DIR/guard-mutability-2.rs:8:37 + | +LL | Some(ref mut y) if let Some(ref mut z) = *y => { + | ^^^^^^^^^ cannot borrow as mutable + | + = note: variables bound in patterns are immutable until the end of the pattern guard + +error: aborting due to previous error + +For more information about this error, try `rustc --explain E0596`. diff --git a/tests/ui/rfcs/rfc-2294-if-let-guard/macro-expanded.rs b/tests/ui/rfcs/rfc-2294-if-let-guard/macro-expanded.rs new file mode 100644 index 00000000000..423a2cd53fc --- /dev/null +++ b/tests/ui/rfcs/rfc-2294-if-let-guard/macro-expanded.rs @@ -0,0 +1,16 @@ +// Expression macros can't expand to a let match guard. + +#![feature(if_let_guard)] +#![feature(let_chains)] + +macro_rules! m { + ($e:expr) => { let Some(x) = $e } + //~^ ERROR expected expression, found `let` statement +} + +fn main() { + match () { + () if m!(Some(5)) => {} + _ => {} + } +} diff --git a/tests/ui/rfcs/rfc-2294-if-let-guard/macro-expanded.stderr b/tests/ui/rfcs/rfc-2294-if-let-guard/macro-expanded.stderr new file mode 100644 index 00000000000..41a20bf8ae1 --- /dev/null +++ b/tests/ui/rfcs/rfc-2294-if-let-guard/macro-expanded.stderr @@ -0,0 +1,13 @@ +error: expected expression, found `let` statement + --> $DIR/macro-expanded.rs:7:20 + | +LL | ($e:expr) => { let Some(x) = $e } + | ^^^ +... +LL | () if m!(Some(5)) => {} + | ----------- in this macro invocation + | + = note: this error originates in the macro `m` (in Nightly builds, run with -Z macro-backtrace for more info) + +error: aborting due to previous error + diff --git a/tests/ui/rfcs/rfc-2294-if-let-guard/parens.rs b/tests/ui/rfcs/rfc-2294-if-let-guard/parens.rs new file mode 100644 index 00000000000..9cb27c73b14 --- /dev/null +++ b/tests/ui/rfcs/rfc-2294-if-let-guard/parens.rs @@ -0,0 +1,27 @@ +// Parenthesised let "expressions" are not allowed in guards + +#![feature(if_let_guard)] +#![feature(let_chains)] + +#[cfg(FALSE)] +fn un_cfged() { + match () { + () if let 0 = 1 => {} + () if (let 0 = 1) => {} + //~^ ERROR expected expression, found `let` statement + () if (((let 0 = 1))) => {} + //~^ ERROR expected expression, found `let` statement + } +} + +fn main() { + match () { + () if let 0 = 1 => {} + () if (let 0 = 1) => {} + //~^ ERROR expected expression, found `let` statement + //~| ERROR `let` expressions are not supported here + () if (((let 0 = 1))) => {} + //~^ ERROR expected expression, found `let` statement + //~| ERROR `let` expressions are not supported here + } +} diff --git a/tests/ui/rfcs/rfc-2294-if-let-guard/parens.stderr b/tests/ui/rfcs/rfc-2294-if-let-guard/parens.stderr new file mode 100644 index 00000000000..85df360daab --- /dev/null +++ b/tests/ui/rfcs/rfc-2294-if-let-guard/parens.stderr @@ -0,0 +1,52 @@ +error: expected expression, found `let` statement + --> $DIR/parens.rs:10:16 + | +LL | () if (let 0 = 1) => {} + | ^^^ + +error: expected expression, found `let` statement + --> $DIR/parens.rs:12:18 + | +LL | () if (((let 0 = 1))) => {} + | ^^^ + +error: expected expression, found `let` statement + --> $DIR/parens.rs:20:16 + | +LL | () if (let 0 = 1) => {} + | ^^^ + +error: expected expression, found `let` statement + --> $DIR/parens.rs:23:18 + | +LL | () if (((let 0 = 1))) => {} + | ^^^ + +error: `let` expressions are not supported here + --> $DIR/parens.rs:20:16 + | +LL | () if (let 0 = 1) => {} + | ^^^^^^^^^ + | + = note: only supported directly in conditions of `if` and `while` expressions +note: `let`s wrapped in parentheses are not supported in a context with let chains + --> $DIR/parens.rs:20:16 + | +LL | () if (let 0 = 1) => {} + | ^^^^^^^^^ + +error: `let` expressions are not supported here + --> $DIR/parens.rs:23:18 + | +LL | () if (((let 0 = 1))) => {} + | ^^^^^^^^^ + | + = note: only supported directly in conditions of `if` and `while` expressions +note: `let`s wrapped in parentheses are not supported in a context with let chains + --> $DIR/parens.rs:23:18 + | +LL | () if (((let 0 = 1))) => {} + | ^^^^^^^^^ + +error: aborting due to 6 previous errors + diff --git a/tests/ui/rfcs/rfc-2294-if-let-guard/partially-macro-expanded.rs b/tests/ui/rfcs/rfc-2294-if-let-guard/partially-macro-expanded.rs new file mode 100644 index 00000000000..d91b3a358da --- /dev/null +++ b/tests/ui/rfcs/rfc-2294-if-let-guard/partially-macro-expanded.rs @@ -0,0 +1,18 @@ +// Macros can be used for (parts of) the pattern and expression in an if let guard +// check-pass + +#![feature(if_let_guard)] +#![feature(let_chains)] + +macro_rules! m { + (pattern $i:ident) => { Some($i) }; + (expression $e:expr) => { $e }; +} + +fn main() { + match () { + () if let m!(pattern x) = m!(expression Some(4)) => {} + () if let [m!(pattern y)] = [Some(8 + m!(expression 4))] => {} + _ => {} + } +} diff --git a/tests/ui/rfcs/rfc-2294-if-let-guard/shadowing.rs b/tests/ui/rfcs/rfc-2294-if-let-guard/shadowing.rs new file mode 100644 index 00000000000..dba292ef9e2 --- /dev/null +++ b/tests/ui/rfcs/rfc-2294-if-let-guard/shadowing.rs @@ -0,0 +1,23 @@ +// Check shadowing in if let guards works as expected. +// check-pass + +#![feature(if_let_guard)] +#![feature(let_chains)] + +fn main() { + let x: Option> = Some(Some(6)); + match x { + Some(x) if let Some(x) = x => { + let _: i32 = x; + } + _ => {} + } + + let y: Option>> = Some(Some(Some(-24))); + match y { + Some(y) if let Some(y) = y && let Some(y) = y => { + let _: i32 = y; + } + _ => {} + } +}