[gcc r13-2629] libstdc++: Add already-accepted <ranges> testcase [PR106320]

[gcc r13-2629] libstdc++: Add already-accepted <ranges> testcase [PR106320]

[Patrick Palka]

https://gcc.gnu.org/g:db19cfdac8ede93172aecc58612171c239c993ad

commit r13-2629-gdb19cfdac8ede93172aecc58612171c239c993ad
Author: Patrick Palka <ppalka@redhat.com>
Date:   Mon Sep 12 15:05:04 2022 -0400

    libstdc++: Add already-accepted <ranges> testcase [PR106320]
    
    Although PR106320 affected only the 10 and 11 branches, and the testcase
    from there is already correctly accepted on trunk and the 12 branch, we
    still should add the testcase to trunk/12 too for inter-branch consistency.
    
            PR libstdc++/106320
    
    libstdc++-v3/ChangeLog:
    
            * testsuite/std/ranges/adaptors/join.cc (test13): New test.

Diff:
---
 libstdc++-v3/testsuite/std/ranges/adaptors/join.cc | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/libstdc++-v3/testsuite/std/ranges/adaptors/join.cc b/libstdc++-v3/testsuite/std/ranges/adaptors/join.cc
index 8986f718229..530ab6663b5 100644
--- a/libstdc++-v3/testsuite/std/ranges/adaptors/join.cc
+++ b/libstdc++-v3/testsuite/std/ranges/adaptors/join.cc
@@ -205,6 +205,18 @@ test12()
   }();
 }
 
+void
+test13()
+{
+  // PR libstdc++/106320
+  auto l = std::views::transform([](auto x) {
+    return x | std::views::transform([i=0](auto y) {
+      return y;
+    });
+  });
+  std::vector<std::vector<int>> v{{5, 6, 7}};
+  v | l | std::views::join;
+}
 int
 main()
 {
@@ -220,4 +232,5 @@ main()
   test10();
   test11();
   test12();
+  test13();
 }