1 files changed, 117 insertions, 0 deletions
diff --git a/mfbt/tests/TestBitSet.cpp b/mfbt/tests/TestBitSet.cpp
new file mode 100644
index 0000000000..2bd1923a15
--- /dev/null
+++ b/mfbt/tests/TestBitSet.cpp
@@ -0,0 +1,117 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "mozilla/Assertions.h"
+#include "mozilla/BitSet.h"
+
+using mozilla::BitSet;
+
+template <typename Storage>
+class BitSetSuite {
+  template <size_t N>
+  using TestBitSet = BitSet<N, Storage>;
+
+  static constexpr size_t kBitsPerWord = sizeof(Storage) * 8;
+
+  static constexpr Storage kAllBitsSet = ~Storage{0};
+
+ public:
+  void testLength() {
+    MOZ_RELEASE_ASSERT(TestBitSet<1>().Storage().LengthBytes() ==
+                       sizeof(Storage));
+
+    MOZ_RELEASE_ASSERT(TestBitSet<1>().Storage().Length() == 1);
+    MOZ_RELEASE_ASSERT(TestBitSet<kBitsPerWord>().Storage().Length() == 1);
+    MOZ_RELEASE_ASSERT(TestBitSet<kBitsPerWord + 1>().Storage().Length() == 2);
+  }
+
+  void testConstruct() {
+    MOZ_RELEASE_ASSERT(TestBitSet<1>().Storage()[0] == 0);
+    MOZ_RELEASE_ASSERT(TestBitSet<kBitsPerWord>().Storage()[0] == 0);
+    MOZ_RELEASE_ASSERT(TestBitSet<kBitsPerWord + 1>().Storage()[0] == 0);
+    MOZ_RELEASE_ASSERT(TestBitSet<kBitsPerWord + 1>().Storage()[1] == 0);
+
+    TestBitSet<1> bitset1;
+    bitset1.SetAll();
+    TestBitSet<kBitsPerWord> bitsetW;
+    bitsetW.SetAll();
+    TestBitSet<kBitsPerWord + 1> bitsetW1;
+    bitsetW1.SetAll();
+
+    MOZ_RELEASE_ASSERT(bitset1.Storage()[0] == 1);
+    MOZ_RELEASE_ASSERT(bitsetW.Storage()[0] == kAllBitsSet);
+    MOZ_RELEASE_ASSERT(bitsetW1.Storage()[0] == kAllBitsSet);
+    MOZ_RELEASE_ASSERT(bitsetW1.Storage()[1] == 1);
+
+    MOZ_RELEASE_ASSERT(TestBitSet<1>(bitset1).Storage()[0] == 1);
+    MOZ_RELEASE_ASSERT(TestBitSet<kBitsPerWord>(bitsetW).Storage()[0] ==
+                       kAllBitsSet);
+    MOZ_RELEASE_ASSERT(TestBitSet<kBitsPerWord + 1>(bitsetW1).Storage()[0] ==
+                       kAllBitsSet);
+    MOZ_RELEASE_ASSERT(TestBitSet<kBitsPerWord + 1>(bitsetW1).Storage()[1] ==
+                       1);
+
+    MOZ_RELEASE_ASSERT(TestBitSet<1>(bitset1.Storage()).Storage()[0] == 1);
+    MOZ_RELEASE_ASSERT(
+        TestBitSet<kBitsPerWord>(bitsetW.Storage()).Storage()[0] ==
+        kAllBitsSet);
+    MOZ_RELEASE_ASSERT(
+        TestBitSet<kBitsPerWord + 1>(bitsetW1.Storage()).Storage()[0] ==
+        kAllBitsSet);
+    MOZ_RELEASE_ASSERT(
+        TestBitSet<kBitsPerWord + 1>(bitsetW1.Storage()).Storage()[1] == 1);
+  }
+
+  void testSetBit() {
+    TestBitSet<kBitsPerWord + 2> bitset;
+    MOZ_RELEASE_ASSERT(!bitset.Test(3));
+    MOZ_RELEASE_ASSERT(!bitset[3]);
+    MOZ_RELEASE_ASSERT(!bitset.Test(kBitsPerWord + 1));
+    MOZ_RELEASE_ASSERT(!bitset[kBitsPerWord + 1]);
+
+    bitset[3] = true;
+    MOZ_RELEASE_ASSERT(bitset.Test(3));
+    MOZ_RELEASE_ASSERT(bitset[3]);
+
+    bitset[kBitsPerWord + 1] = true;
+    MOZ_RELEASE_ASSERT(bitset.Test(3));
+    MOZ_RELEASE_ASSERT(bitset[3]);
+    MOZ_RELEASE_ASSERT(bitset.Test(kBitsPerWord + 1));
+    MOZ_RELEASE_ASSERT(bitset[kBitsPerWord + 1]);
+
+    bitset.ResetAll();
+    for (size_t i = 0; i < decltype(bitset)::Size(); i++) {
+      MOZ_RELEASE_ASSERT(!bitset[i]);
+    }
+
+    bitset.SetAll();
+    for (size_t i = 0; i < decltype(bitset)::Size(); i++) {
+      MOZ_RELEASE_ASSERT(bitset[i]);
+    }
+
+    // Test trailing unused bits are not set by SetAll().
+    MOZ_RELEASE_ASSERT(bitset.Storage()[1] == 3);
+
+    bitset.ResetAll();
+    for (size_t i = 0; i < decltype(bitset)::Size(); i++) {
+      MOZ_RELEASE_ASSERT(!bitset[i]);
+    }
+  }
+
+  void runTests() {
+    testLength();
+    testConstruct();
+    testSetBit();
+  }
+};
+
+int main() {
+  BitSetSuite<uint8_t>().runTests();
+  BitSetSuite<uint32_t>().runTests();
+  BitSetSuite<uint64_t>().runTests();
+
+  return 0;
+}