7 files changed, 40 insertions, 7 deletions

diff --git a/Cargo.lock b/Cargo.lock
index fbb79e01f..47381c08e 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -1827,9 +1827,7 @@ checksum = "56dee185309b50d1f11bfedef0fe6d036842e3fb77413abef29f8f8d1c5d4c1c"
 
 [[package]]
 name = "ungrammar"
-version = "1.4.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "68951379f3ced25754472ca5addbf74d7dab58c9818f49290a3d8caa3ab44fb7"
+version = "1.5.0"
 
 [[package]]
 name = "unicase"
diff --git a/Cargo.toml b/Cargo.toml
index 59d36fbc1..fdf2a71a0 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -26,4 +26,4 @@ debug = 0 # Set this to 1 or 2 to get more useful backtraces in debugger.
 # chalk-ir = { path = "../chalk/chalk-ir" }
 # chalk-recursive = { path = "../chalk/chalk-recursive" }
 
-# ungrammar = { path = "../ungrammar" }
+ungrammar = { path = "../ungrammar" }
diff --git a/crates/hir_def/src/body/lower.rs b/crates/hir_def/src/body/lower.rs
index 0f404be1b..978c3a324 100644
--- a/crates/hir_def/src/body/lower.rs
+++ b/crates/hir_def/src/body/lower.rs
@@ -933,7 +933,9 @@ impl ExprCollector<'_> {
                 Pat::Box { inner }
             }
             // FIXME: implement
-            ast::Pat::RangePat(_) | ast::Pat::MacroPat(_) => Pat::Missing,
+            ast::Pat::RangePat(_) | ast::Pat::MacroPat(_) | ast::Pat::ConstBlockPat(_) => {
+                Pat::Missing
+            }
         };
         let ptr = AstPtr::new(&pat);
         self.alloc_pat(pattern, Either::Left(ptr))
diff --git a/crates/parser/src/syntax_kind/generated.rs b/crates/parser/src/syntax_kind/generated.rs
index 980aa5979..f69e71bdb 100644
--- a/crates/parser/src/syntax_kind/generated.rs
+++ b/crates/parser/src/syntax_kind/generated.rs
@@ -170,6 +170,7 @@ pub enum SyntaxKind {
     RANGE_PAT,
     LITERAL_PAT,
     MACRO_PAT,
+    CONST_BLOCK_PAT,
     TUPLE_EXPR,
     ARRAY_EXPR,
     PAREN_EXPR,
diff --git a/crates/syntax/src/ast/generated/nodes.rs b/crates/syntax/src/ast/generated/nodes.rs
index 1588ba93e..c5b80bffe 100644
--- a/crates/syntax/src/ast/generated/nodes.rs
+++ b/crates/syntax/src/ast/generated/nodes.rs
@@ -763,6 +763,7 @@ impl EffectExpr {
     pub fn try_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![try]) }
     pub fn unsafe_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![unsafe]) }
     pub fn async_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![async]) }
+    pub fn const_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![const]) }
     pub fn block_expr(&self) -> Option<BlockExpr> { support::child(&self.syntax) }
 }
 #[derive(Debug, Clone, PartialEq, Eq, Hash)]
@@ -1251,6 +1252,14 @@ impl TupleStructPat {
     pub fn r_paren_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![')']) }
 }
 #[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct ConstBlockPat {
+    pub(crate) syntax: SyntaxNode,
+}
+impl ConstBlockPat {
+    pub fn const_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![const]) }
+    pub fn block_expr(&self) -> Option<BlockExpr> { support::child(&self.syntax) }
+}
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
 pub struct RecordPatFieldList {
     pub(crate) syntax: SyntaxNode,
 }
@@ -1369,6 +1378,7 @@ pub enum Pat {
     SlicePat(SlicePat),
     TuplePat(TuplePat),
     TupleStructPat(TupleStructPat),
+    ConstBlockPat(ConstBlockPat),
 }
 #[derive(Debug, Clone, PartialEq, Eq, Hash)]
 pub enum FieldList {
@@ -2772,6 +2782,17 @@ impl AstNode for TupleStructPat {
     }
     fn syntax(&self) -> &SyntaxNode { &self.syntax }
 }
+impl AstNode for ConstBlockPat {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == CONST_BLOCK_PAT }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode { &self.syntax }
+}
 impl AstNode for RecordPatFieldList {
     fn can_cast(kind: SyntaxKind) -> bool { kind == RECORD_PAT_FIELD_LIST }
     fn cast(syntax: SyntaxNode) -> Option<Self> {
@@ -3242,12 +3263,15 @@ impl From<TuplePat> for Pat {
 impl From<TupleStructPat> for Pat {
     fn from(node: TupleStructPat) -> Pat { Pat::TupleStructPat(node) }
 }
+impl From<ConstBlockPat> for Pat {
+    fn from(node: ConstBlockPat) -> Pat { Pat::ConstBlockPat(node) }
+}
 impl AstNode for Pat {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
             IDENT_PAT | BOX_PAT | REST_PAT | LITERAL_PAT | MACRO_PAT | OR_PAT | PAREN_PAT
             | PATH_PAT | WILDCARD_PAT | RANGE_PAT | RECORD_PAT | REF_PAT | SLICE_PAT
-            | TUPLE_PAT | TUPLE_STRUCT_PAT => true,
+            | TUPLE_PAT | TUPLE_STRUCT_PAT | CONST_BLOCK_PAT => true,
             _ => false,
         }
     }
@@ -3268,6 +3292,7 @@ impl AstNode for Pat {
             SLICE_PAT => Pat::SlicePat(SlicePat { syntax }),
             TUPLE_PAT => Pat::TuplePat(TuplePat { syntax }),
             TUPLE_STRUCT_PAT => Pat::TupleStructPat(TupleStructPat { syntax }),
+            CONST_BLOCK_PAT => Pat::ConstBlockPat(ConstBlockPat { syntax }),
             _ => return None,
         };
         Some(res)
@@ -3289,6 +3314,7 @@ impl AstNode for Pat {
             Pat::SlicePat(it) => &it.syntax,
             Pat::TuplePat(it) => &it.syntax,
             Pat::TupleStructPat(it) => &it.syntax,
+            Pat::ConstBlockPat(it) => &it.syntax,
         }
     }
 }
@@ -4137,6 +4163,11 @@ impl std::fmt::Display for TupleStructPat {
         std::fmt::Display::fmt(self.syntax(), f)
     }
 }
+impl std::fmt::Display for ConstBlockPat {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
 impl std::fmt::Display for RecordPatFieldList {
     fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
         std::fmt::Display::fmt(self.syntax(), f)
diff --git a/xtask/Cargo.toml b/xtask/Cargo.toml
index 78a0b54ba..96b4ea448 100644
--- a/xtask/Cargo.toml
+++ b/xtask/Cargo.toml
@@ -15,7 +15,7 @@ flate2 = "1.0"
 pico-args = "0.3.1"
 proc-macro2 = "1.0.8"
 quote = "1.0.2"
-ungrammar = "1.4"
+ungrammar = "1.5"
 walkdir = "2.3.1"
 write-json = "0.1.0"
 xshell = "0.1"
diff --git a/xtask/src/ast_src.rs b/xtask/src/ast_src.rs
index a69ced5cc..2b8012bdd 100644
--- a/xtask/src/ast_src.rs
+++ b/xtask/src/ast_src.rs
@@ -132,6 +132,7 @@ pub(crate) const KINDS_SRC: KindsSrc = KindsSrc {
         "RANGE_PAT",
         "LITERAL_PAT",
         "MACRO_PAT",
+        "CONST_BLOCK_PAT",
         // atoms
         "TUPLE_EXPR",
         "ARRAY_EXPR",