1 files changed, 56 insertions, 0 deletions
diff --git a/protocols/Telegram/tdlib/td/tdutils/test/buffer.cpp b/protocols/Telegram/tdlib/td/tdutils/test/buffer.cpp
new file mode 100644
index 0000000000..4bc406cc64
--- /dev/null
+++ b/protocols/Telegram/tdlib/td/tdutils/test/buffer.cpp
@@ -0,0 +1,56 @@
+//
+// Copyright Aliaksei Levin (levlam@telegram.org), Arseny Smirnov (arseny30@gmail.com) 2014-2022
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+#include "td/utils/tests.h"
+
+#include "td/utils/buffer.h"
+#include "td/utils/Random.h"
+
+TEST(Buffer, buffer_builder) {
+  {
+    td::BufferBuilder builder;
+    builder.append("b");
+    builder.prepend("a");
+    builder.append("c");
+    ASSERT_EQ(builder.extract().as_slice(), "abc");
+  }
+  {
+    td::BufferBuilder builder{"hello", 0, 0};
+    ASSERT_EQ(builder.extract().as_slice(), "hello");
+  }
+  {
+    td::BufferBuilder builder{"hello", 1, 1};
+    builder.prepend("A ");
+    builder.append(" B");
+    ASSERT_EQ(builder.extract().as_slice(), "A hello B");
+  }
+  {
+    auto str = td::rand_string('a', 'z', 10000);
+    auto split_str = td::rand_split(str);
+
+    int l = td::Random::fast(0, static_cast<int>(split_str.size() - 1));
+    int r = l;
+    td::BufferBuilder builder(split_str[l], 123, 1000);
+    while (l != 0 || r != static_cast<int>(split_str.size()) - 1) {
+      if (l == 0 || (td::Random::fast_bool() && r != static_cast<int>(split_str.size() - 1))) {
+        r++;
+        if (td::Random::fast_bool()) {
+          builder.append(split_str[r]);
+        } else {
+          builder.append(td::BufferSlice(split_str[r]));
+        }
+      } else {
+        l--;
+        if (td::Random::fast_bool()) {
+          builder.prepend(split_str[l]);
+        } else {
+          builder.prepend(td::BufferSlice(split_str[l]));
+        }
+      }
+    }
+    ASSERT_EQ(builder.extract().as_slice(), str);
+  }
+}