[gcc r14-8057] gccrs: Add new test for closure in closure parsing

[Arthur Cohen]

https://gcc.gnu.org/g:05ddae991b20754b36c46df8a64a630cc3e4d7e5

commit r14-8057-g05ddae991b20754b36c46df8a64a630cc3e4d7e5
Author: Pierre-Emmanuel Patry <pierre-emmanuel.patry@embecosm.com>
Date:   Tue Oct 10 14:16:52 2023 +0200

    gccrs: Add new test for closure in closure parsing
    
    This new test highlight the fix of #2656.
    
    gcc/testsuite/ChangeLog:
    
            * rust/compile/closure_in_closure.rs: New test.
    
    Signed-off-by: Pierre-Emmanuel Patry <pierre-emmanuel.patry@embecosm.com>

Diff:
---
 gcc/testsuite/rust/compile/closure_in_closure.rs | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/gcc/testsuite/rust/compile/closure_in_closure.rs b/gcc/testsuite/rust/compile/closure_in_closure.rs
new file mode 100644
index 00000000000..1a003070f6a
--- /dev/null
+++ b/gcc/testsuite/rust/compile/closure_in_closure.rs
@@ -0,0 +1,8 @@
+// { dg-additional-options "-frust-compile-until=ast" }
+//
+// Do not reformat this test! The default rust format settings will insert a
+// space between closure parameter lists.
+fn main() {
+    let f = |_||x, y| x+y;
+    assert_eq!(f(())(1, 2), 3);
+}