[libcxx-commits] [libcxx] [libc++] Fix ungetc failing after xsgetn (PR #210951)

[Louis Dionne via libcxx-commits]

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@@ -0,0 +1,59 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// FILE_DEPENDENCIES: test.dat
+
+// <fstream>
+
+// streamsize basic_filebuf::xsgetn(char_type*, streamsize);
+
+// Test that xsgetn buffers properly
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ldionne wrote:

Let's explain what's an extension about this.

https://github.com/llvm/llvm-project/pull/210951