From 8b778a5f8d244a402355cc532107372beec4afc8 Mon Sep 17 00:00:00 2001
From: Yuki Okushi <huyuumi.dev@gmail.com>
Date: Fri, 31 Jul 2020 06:52:00 +0900
Subject: [PATCH] Revert "Fix an ICE on an invalid `binding @ ...` in a tuple
 struct pattern"

This reverts commit f5e5eb6f46ef2cf0dd45dba4f975305509334fc6.
---
 src/librustc_resolve/late.rs          | 28 +++++++++------------------
 src/test/ui/issues/issue-74539.rs     | 12 ------------
 src/test/ui/issues/issue-74539.stderr | 21 --------------------
 3 files changed, 9 insertions(+), 52 deletions(-)
 delete mode 100644 src/test/ui/issues/issue-74539.rs
 delete mode 100644 src/test/ui/issues/issue-74539.stderr

diff --git a/src/librustc_resolve/late.rs b/src/librustc_resolve/late.rs
index bcd2c6c1f1c..a8a2ce19b97 100644
--- a/src/librustc_resolve/late.rs
+++ b/src/librustc_resolve/late.rs
@@ -1510,30 +1510,20 @@ impl<'a, 'b, 'ast> LateResolutionVisitor<'a, 'b, 'ast> {
         pat_src: PatternSource,
         bindings: &mut SmallVec<[(PatBoundCtx, FxHashSet<Ident>); 1]>,
     ) {
-        let is_tuple_struct_pat = matches!(pat.kind, PatKind::TupleStruct(_, _));
-
         // Visit all direct subpatterns of this pattern.
         pat.walk(&mut |pat| {
             debug!("resolve_pattern pat={:?} node={:?}", pat, pat.kind);
             match pat.kind {
                 PatKind::Ident(bmode, ident, ref sub) => {
-                    if is_tuple_struct_pat && sub.as_ref().filter(|p| p.is_rest()).is_some() {
-                        // In tuple struct patterns ignore the invalid `ident @ ...`.
-                        // It will be handled as an error by the AST lowering.
-                        self.r
-                            .session
-                            .delay_span_bug(ident.span, "ident in tuple pattern is invalid");
-                    } else {
-                        // First try to resolve the identifier as some existing entity,
-                        // then fall back to a fresh binding.
-                        let has_sub = sub.is_some();
-                        let res = self
-                            .try_resolve_as_non_binding(pat_src, pat, bmode, ident, has_sub)
-                            .unwrap_or_else(|| {
-                                self.fresh_binding(ident, pat.id, pat_src, bindings)
-                            });
-                        self.r.record_partial_res(pat.id, PartialRes::new(res));
-                    }
+                    // First try to resolve the identifier as some existing entity,
+                    // then fall back to a fresh binding.
+                    let has_sub = sub.is_some();
+                    let res = self
+                        .try_resolve_as_non_binding(pat_src, pat, bmode, ident, has_sub)
+                        .unwrap_or_else(|| {
+                            self.fresh_binding(ident, pat.id, pat_src, bindings)
+                        });
+                    self.r.record_partial_res(pat.id, PartialRes::new(res));
                 }
                 PatKind::TupleStruct(ref path, ..) => {
                     self.smart_resolve_path(pat.id, None, path, PathSource::TupleStruct(pat.span));
diff --git a/src/test/ui/issues/issue-74539.rs b/src/test/ui/issues/issue-74539.rs
deleted file mode 100644
index 75632d11c1d..00000000000
--- a/src/test/ui/issues/issue-74539.rs
+++ /dev/null
@@ -1,12 +0,0 @@
-enum E {
-    A(u8, u8),
-}
-
-fn main() {
-    let e = E::A(2, 3);
-    match e {
-        E::A(x @ ..) => {  //~ ERROR `x @` is not allowed in a tuple
-            x //~ ERROR cannot find value `x` in this scope
-        }
-    };
-}
diff --git a/src/test/ui/issues/issue-74539.stderr b/src/test/ui/issues/issue-74539.stderr
deleted file mode 100644
index 94526dcd7cb..00000000000
--- a/src/test/ui/issues/issue-74539.stderr
+++ /dev/null
@@ -1,21 +0,0 @@
-error[E0425]: cannot find value `x` in this scope
-  --> $DIR/issue-74539.rs:9:13
-   |
-LL |             x
-   |             ^ help: a local variable with a similar name exists: `e`
-
-error: `x @` is not allowed in a tuple struct
-  --> $DIR/issue-74539.rs:8:14
-   |
-LL |         E::A(x @ ..) => {
-   |              ^^^^^^ this is only allowed in slice patterns
-   |
-   = help: remove this and bind each tuple field independently
-help: if you don't need to use the contents of x, discard the tuple's remaining fields
-   |
-LL |         E::A(..) => {
-   |              ^^
-
-error: aborting due to 2 previous errors
-
-For more information about this error, try `rustc --explain E0425`.