bendns' repos / rust-analyzer
Unnamed repository; edit this file 'description' to name the repository.
Diffstat (limited to 'crates/parser/src/grammar/patterns.rs')
-rw-r--r--crates/parser/src/grammar/patterns.rs103
1 files changed, 69 insertions, 34 deletions
diff --git a/crates/parser/src/grammar/patterns.rs b/crates/parser/src/grammar/patterns.rs
index 5f4977886f..39ded41bb2 100644
--- a/crates/parser/src/grammar/patterns.rs
+++ b/crates/parser/src/grammar/patterns.rs
@@ -5,6 +5,7 @@ pub(super) const PATTERN_FIRST: TokenSet =
T![box],
T![ref],
T![mut],
+ T![const],
T!['('],
T!['['],
T![&],
@@ -15,6 +16,10 @@ pub(super) const PATTERN_FIRST: TokenSet =
const PAT_TOP_FIRST: TokenSet = PATTERN_FIRST.union(TokenSet::new(&[T![|]]));
+/// Set of possible tokens at the start of a range pattern's end bound.
+const RANGE_PAT_END_FIRST: TokenSet =
+ expressions::LITERAL_FIRST.union(paths::PATH_FIRST).union(TokenSet::new(&[T![-], T![const]]));
+
pub(crate) fn pattern(p: &mut Parser<'_>) {
pattern_r(p, PAT_RECOVERY_SET);
}
@@ -105,6 +110,52 @@ fn pattern_single_r(p: &mut Parser<'_>, recovery_set: TokenSet) {
return;
}
+ // test exclusive_range_pat
+ // fn main() {
+ // match 42 {
+ // ..0 => {}
+ // 1..2 => {}
+ // }
+ // }
+
+ // test dot_dot_pat
+ // fn main() {
+ // let .. = ();
+ // //
+ // // Tuples
+ // //
+ // let (a, ..) = ();
+ // let (a, ..,) = ();
+ // let Tuple(a, ..) = ();
+ // let Tuple(a, ..,) = ();
+ // let (.., ..) = ();
+ // let Tuple(.., ..) = ();
+ // let (.., a, ..) = ();
+ // let Tuple(.., a, ..) = ();
+ // //
+ // // Slices
+ // //
+ // let [..] = ();
+ // let [head, ..] = ();
+ // let [head, tail @ ..] = ();
+ // let [head, .., cons] = ();
+ // let [head, mid @ .., cons] = ();
+ // let [head, .., .., cons] = ();
+ // let [head, .., mid, tail @ ..] = ();
+ // let [head, .., mid, .., cons] = ();
+ // }
+ if p.at(T![..]) {
+ let m = p.start();
+ p.bump(T![..]);
+ if p.at_ts(RANGE_PAT_END_FIRST) {
+ atom_pat(p, recovery_set);
+ m.complete(p, RANGE_PAT);
+ } else {
+ m.complete(p, REST_PAT);
+ }
+ return;
+ }
+
if let Some(lhs) = atom_pat(p, recovery_set) {
for range_op in [T![...], T![..=], T![..]] {
if p.at(range_op) {
@@ -173,7 +224,6 @@ fn atom_pat(p: &mut Parser<'_>, recovery_set: TokenSet) -> Option<CompletedMarke
_ if paths::is_path_start(p) => path_or_macro_pat(p),
_ if is_literal_pat_start(p) => literal_pat(p),
- T![.] if p.at(T![..]) => rest_pat(p),
T![_] => wildcard_pat(p),
T![&] => ref_pat(p),
T!['('] => tuple_pat(p),
@@ -334,39 +384,6 @@ fn wildcard_pat(p: &mut Parser<'_>) -> CompletedMarker {
m.complete(p, WILDCARD_PAT)
}
-// test dot_dot_pat
-// fn main() {
-// let .. = ();
-// //
-// // Tuples
-// //
-// let (a, ..) = ();
-// let (a, ..,) = ();
-// let Tuple(a, ..) = ();
-// let Tuple(a, ..,) = ();
-// let (.., ..) = ();
-// let Tuple(.., ..) = ();
-// let (.., a, ..) = ();
-// let Tuple(.., a, ..) = ();
-// //
-// // Slices
-// //
-// let [..] = ();
-// let [head, ..] = ();
-// let [head, tail @ ..] = ();
-// let [head, .., cons] = ();
-// let [head, mid @ .., cons] = ();
-// let [head, .., .., cons] = ();
-// let [head, .., mid, tail @ ..] = ();
-// let [head, .., mid, .., cons] = ();
-// }
-fn rest_pat(p: &mut Parser<'_>) -> CompletedMarker {
- assert!(p.at(T![..]));
- let m = p.start();
- p.bump(T![..]);
- m.complete(p, REST_PAT)
-}
-
// test ref_pat
// fn main() {
// let &a = ();
@@ -396,6 +413,16 @@ fn tuple_pat(p: &mut Parser<'_>) -> CompletedMarker {
let mut has_comma = false;
let mut has_pat = false;
let mut has_rest = false;
+
+ // test_err tuple_pat_leading_comma
+ // fn foo() {
+ // let (,);
+ // }
+ if p.eat(T![,]) {
+ p.error("expected pattern");
+ has_comma = true;
+ }
+
while !p.at(EOF) && !p.at(T![')']) {
has_pat = true;
if !p.at_ts(PAT_TOP_FIRST) {
@@ -483,6 +510,14 @@ fn box_pat(p: &mut Parser<'_>) -> CompletedMarker {
// fn main() {
// let const { 15 } = ();
// let const { foo(); bar() } = ();
+//
+// match 42 {
+// const { 0 } .. const { 1 } => (),
+// .. const { 0 } => (),
+// const { 2 } .. => (),
+// }
+//
+// let (const { () },) = ();
// }
fn const_block_pat(p: &mut Parser<'_>) -> CompletedMarker {
assert!(p.at(T![const]));