diff --git a/src/test/ui/pattern/rest-pat-semantic-disallowed.rs b/src/test/ui/pattern/rest-pat-semantic-disallowed.rs new file mode 100644 index 0000000000000..36a45a3ccdc4b --- /dev/null +++ b/src/test/ui/pattern/rest-pat-semantic-disallowed.rs @@ -0,0 +1,82 @@ +// Here we test that rest patterns, i.e. `..`, are not allowed +// outside of slice (+ ident patterns witin those), tuple, +// and tuple struct patterns and that duplicates are caught in these contexts. + +#![feature(slice_patterns, box_patterns)] + +fn main() {} + +macro_rules! mk_pat { + () => { .. } //~ ERROR `..` patterns are not allowed here +} + +fn rest_patterns() { + let mk_pat!(); + + // Top level: + fn foo(..: u8) {} //~ ERROR `..` patterns are not allowed here + let ..; //~ ERROR `..` patterns are not allowed here + + // Box patterns: + let box ..; //~ ERROR `..` patterns are not allowed here + + // In or-patterns: + match 1 { + 1 | .. => {} //~ ERROR `..` patterns are not allowed here + } + + // Ref patterns: + let &..; //~ ERROR `..` patterns are not allowed here + let &mut ..; //~ ERROR `..` patterns are not allowed here + + // Ident patterns: + let x @ ..; //~ ERROR `..` patterns are not allowed here + let ref x @ ..; //~ ERROR `..` patterns are not allowed here + let ref mut x @ ..; //~ ERROR `..` patterns are not allowed here + + // Tuple: + let (..): (u8,); // OK. + let (..,): (u8,); // OK. + let ( + .., + .., //~ ERROR `..` can only be used once per tuple pattern + .. //~ ERROR `..` can only be used once per tuple pattern + ): (u8, u8, u8); + let ( + .., + x, + .. //~ ERROR `..` can only be used once per tuple pattern + ): (u8, u8, u8); + + struct A(u8, u8, u8); + + // Tuple struct (same idea as for tuple patterns): + let A(..); // OK. + let A(..,); // OK. + let A( + .., + .., //~ ERROR `..` can only be used once per tuple struct pattern + .. //~ ERROR `..` can only be used once per tuple struct pattern + ); + let A( + .., + x, + .. //~ ERROR `..` can only be used once per tuple struct pattern + ); + + // Array/Slice: + let [..]: &[u8]; // OK. + let [..,]: &[u8]; // OK. + let [ + .., + .., //~ ERROR `..` can only be used once per slice pattern + .. //~ ERROR `..` can only be used once per slice pattern + ]: &[u8]; + let [ + .., + ref x @ .., //~ ERROR `..` can only be used once per slice pattern + ref mut y @ .., //~ ERROR `..` can only be used once per slice pattern + (ref z @ ..), //~ ERROR `..` patterns are not allowed here + .. //~ ERROR `..` can only be used once per slice pattern + ]: &[u8]; +} diff --git a/src/test/ui/pattern/rest-pat-semantic-disallowed.stderr b/src/test/ui/pattern/rest-pat-semantic-disallowed.stderr new file mode 100644 index 0000000000000..826f76b356cf1 --- /dev/null +++ b/src/test/ui/pattern/rest-pat-semantic-disallowed.stderr @@ -0,0 +1,188 @@ +error: `..` patterns are not allowed here + --> $DIR/rest-pat-semantic-disallowed.rs:10:13 + | +LL | () => { .. } + | ^^ +... +LL | let mk_pat!(); + | --------- in this macro invocation + | + = note: only allowed in tuple, tuple struct, and slice patterns + +error: `..` patterns are not allowed here + --> $DIR/rest-pat-semantic-disallowed.rs:18:9 + | +LL | let ..; + | ^^ + | + = note: only allowed in tuple, tuple struct, and slice patterns + +error: `..` patterns are not allowed here + --> $DIR/rest-pat-semantic-disallowed.rs:21:13 + | +LL | let box ..; + | ^^ + | + = note: only allowed in tuple, tuple struct, and slice patterns + +error: `..` patterns are not allowed here + --> $DIR/rest-pat-semantic-disallowed.rs:25:13 + | +LL | 1 | .. => {} + | ^^ + | + = note: only allowed in tuple, tuple struct, and slice patterns + +error: `..` patterns are not allowed here + --> $DIR/rest-pat-semantic-disallowed.rs:29:10 + | +LL | let &..; + | ^^ + | + = note: only allowed in tuple, tuple struct, and slice patterns + +error: `..` patterns are not allowed here + --> $DIR/rest-pat-semantic-disallowed.rs:30:14 + | +LL | let &mut ..; + | ^^ + | + = note: only allowed in tuple, tuple struct, and slice patterns + +error: `..` patterns are not allowed here + --> $DIR/rest-pat-semantic-disallowed.rs:33:13 + | +LL | let x @ ..; + | ^^ + | + = note: only allowed in tuple, tuple struct, and slice patterns + +error: `..` patterns are not allowed here + --> $DIR/rest-pat-semantic-disallowed.rs:34:17 + | +LL | let ref x @ ..; + | ^^ + | + = note: only allowed in tuple, tuple struct, and slice patterns + +error: `..` patterns are not allowed here + --> $DIR/rest-pat-semantic-disallowed.rs:35:21 + | +LL | let ref mut x @ ..; + | ^^ + | + = note: only allowed in tuple, tuple struct, and slice patterns + +error: `..` can only be used once per tuple pattern + --> $DIR/rest-pat-semantic-disallowed.rs:42:9 + | +LL | .., + | -- previously used here +LL | .., + | ^^ can only be used once per tuple pattern + +error: `..` can only be used once per tuple pattern + --> $DIR/rest-pat-semantic-disallowed.rs:43:9 + | +LL | .., + | -- previously used here +LL | .., +LL | .. + | ^^ can only be used once per tuple pattern + +error: `..` can only be used once per tuple pattern + --> $DIR/rest-pat-semantic-disallowed.rs:48:9 + | +LL | .., + | -- previously used here +LL | x, +LL | .. + | ^^ can only be used once per tuple pattern + +error: `..` can only be used once per tuple struct pattern + --> $DIR/rest-pat-semantic-disallowed.rs:58:9 + | +LL | .., + | -- previously used here +LL | .., + | ^^ can only be used once per tuple struct pattern + +error: `..` can only be used once per tuple struct pattern + --> $DIR/rest-pat-semantic-disallowed.rs:59:9 + | +LL | .., + | -- previously used here +LL | .., +LL | .. + | ^^ can only be used once per tuple struct pattern + +error: `..` can only be used once per tuple struct pattern + --> $DIR/rest-pat-semantic-disallowed.rs:64:9 + | +LL | .., + | -- previously used here +LL | x, +LL | .. + | ^^ can only be used once per tuple struct pattern + +error: `..` can only be used once per slice pattern + --> $DIR/rest-pat-semantic-disallowed.rs:72:9 + | +LL | .., + | -- previously used here +LL | .., + | ^^ can only be used once per slice pattern + +error: `..` can only be used once per slice pattern + --> $DIR/rest-pat-semantic-disallowed.rs:73:9 + | +LL | .., + | -- previously used here +LL | .., +LL | .. + | ^^ can only be used once per slice pattern + +error: `..` can only be used once per slice pattern + --> $DIR/rest-pat-semantic-disallowed.rs:77:17 + | +LL | .., + | -- previously used here +LL | ref x @ .., + | ^^ can only be used once per slice pattern + +error: `..` can only be used once per slice pattern + --> $DIR/rest-pat-semantic-disallowed.rs:78:21 + | +LL | .., + | -- previously used here +LL | ref x @ .., +LL | ref mut y @ .., + | ^^ can only be used once per slice pattern + +error: `..` patterns are not allowed here + --> $DIR/rest-pat-semantic-disallowed.rs:79:18 + | +LL | (ref z @ ..), + | ^^ + | + = note: only allowed in tuple, tuple struct, and slice patterns + +error: `..` can only be used once per slice pattern + --> $DIR/rest-pat-semantic-disallowed.rs:80:9 + | +LL | .., + | -- previously used here +... +LL | .. + | ^^ can only be used once per slice pattern + +error: `..` patterns are not allowed here + --> $DIR/rest-pat-semantic-disallowed.rs:17:12 + | +LL | fn foo(..: u8) {} + | ^^ + | + = note: only allowed in tuple, tuple struct, and slice patterns + +error: aborting due to 22 previous errors + diff --git a/src/test/ui/pattern/rest-pat-syntactic.rs b/src/test/ui/pattern/rest-pat-syntactic.rs new file mode 100644 index 0000000000000..9656a0b5de9ce --- /dev/null +++ b/src/test/ui/pattern/rest-pat-syntactic.rs @@ -0,0 +1,70 @@ +// Here we test that `..` is allowed in all pattern locations *syntactically*. +// The semantic test is in `rest-pat-semantic-disallowed.rs`. + +// check-pass + +fn main() {} + +macro_rules! accept_pat { + ($p:pat) => {} +} + +accept_pat!(..); + +#[cfg(FALSE)] +fn rest_patterns() { + // Top level: + fn foo(..: u8) {} + let ..; + + // Box patterns: + let box ..; + + // In or-patterns: + match x { + .. | .. => {} + } + + // Ref patterns: + let &..; + let &mut ..; + + // Ident patterns: + let x @ ..; + let ref x @ ..; + let ref mut x @ ..; + + // Tuple: + let (..); // This is interpreted as a tuple pattern, not a parenthesis one. + let (..,); // Allowing trailing comma. + let (.., .., ..); // Duplicates also. + let (.., P, ..); // Including with things in between. + + // Tuple struct (same idea as for tuple patterns): + let A(..); + let A(..,); + let A(.., .., ..); + let A(.., P, ..); + + // Array/Slice (like with tuple patterns): + let [..]; + let [..,]; + let [.., .., ..]; + let [.., P, ..]; + + // Random walk to guard against special casing: + match x { + .. | + [ + ( + box .., + &(..), + &mut .., + x @ .. + ), + ref x @ .., + ] | + ref mut x @ .. + => {} + } +}