From 98a5e9bf41b8665ac7ba798d480a9ddf76a3ebbe Mon Sep 17 00:00:00 2001
From: David Tolnay <dtolnay@gmail.com>
Date: Thu, 26 Nov 2020 21:52:55 -0800
Subject: [PATCH] Parse const blocks in pattern position

---
 src/pat.rs        | 14 ++++++++++++++
 tests/repo/mod.rs |  3 +--
 2 files changed, 15 insertions(+), 2 deletions(-)

diff --git a/src/pat.rs b/src/pat.rs
index 6ae17dd5d8..01a507c010 100644
--- a/src/pat.rs
+++ b/src/pat.rs
@@ -343,6 +343,8 @@ pub mod parsing {
                 input.call(pat_slice).map(Pat::Slice)
             } else if lookahead.peek(Token![..]) && !input.peek(Token![...]) {
                 pat_range_half_open(input, begin)
+            } else if lookahead.peek(Token![const]) {
+                input.call(pat_const).map(Pat::Verbatim)
             } else {
                 Err(lookahead.error())
             }
@@ -690,6 +692,18 @@ pub mod parsing {
         })
     }
 
+    fn pat_const(input: ParseStream) -> Result<TokenStream> {
+        let begin = input.fork();
+        input.parse::<Token![const]>()?;
+
+        let content;
+        braced!(content in input);
+        content.call(Attribute::parse_inner)?;
+        content.call(Block::parse_within)?;
+
+        Ok(verbatim::between(begin, input))
+    }
+
     pub fn multi_pat(input: ParseStream) -> Result<Pat> {
         multi_pat_impl(input, None)
     }
diff --git a/tests/repo/mod.rs b/tests/repo/mod.rs
index 8b4445492f..b656838a72 100644
--- a/tests/repo/mod.rs
+++ b/tests/repo/mod.rs
@@ -12,9 +12,8 @@ const REVISION: &str = "9d78d1d02761b906038ba4d54c5f3427f920f5fb";
 
 #[rustfmt::skip]
 static EXCLUDE: &[&str] = &[
-    // TODO: const block in pattern position (#921)
+    // TODO: const block in range patterns (#921)
     "src/test/ui/inline-const/const-match-pat-range.rs",
-    "src/test/ui/inline-const/const-match-pat.rs",
 
     // Compile-fail expr parameter in const generic position: f::<1 + 2>()
     "src/test/ui/const-generics/closing-args-token.rs",