diff options
Diffstat (limited to 'third_party/abseil-cpp/absl/strings/cord_test.cc')
-rw-r--r-- | third_party/abseil-cpp/absl/strings/cord_test.cc | 73 |
1 files changed, 68 insertions, 5 deletions
diff --git a/third_party/abseil-cpp/absl/strings/cord_test.cc b/third_party/abseil-cpp/absl/strings/cord_test.cc index f9982428b3..14eca15573 100644 --- a/third_party/abseil-cpp/absl/strings/cord_test.cc +++ b/third_party/abseil-cpp/absl/strings/cord_test.cc @@ -35,6 +35,7 @@ #include "absl/base/macros.h" #include "absl/container/fixed_array.h" #include "absl/strings/cord_test_helpers.h" +#include "absl/strings/cordz_test_helpers.h" #include "absl/strings/str_cat.h" #include "absl/strings/str_format.h" #include "absl/strings/string_view.h" @@ -187,6 +188,19 @@ class CordTestPeer { static cord_internal::CordzInfo* GetCordzInfo(const Cord& c) { return c.contents_.cordz_info(); } + + static Cord MakeSubstring(Cord src, size_t offset, size_t length) { + ABSL_RAW_CHECK(src.contents_.is_tree(), "Can not be inlined"); + Cord cord; + auto* rep = new cord_internal::CordRepSubstring; + rep->tag = cord_internal::SUBSTRING; + rep->child = cord_internal::CordRep::Ref(src.contents_.tree()); + rep->start = offset; + rep->length = length; + cord.contents_.EmplaceTree(rep, + cord_internal::CordzUpdateTracker::kSubCord); + return cord; + } }; ABSL_NAMESPACE_END @@ -227,7 +241,6 @@ TEST(GigabyteCord, FromExternal) { // caused crashes in production. We grow exponentially so that the code will // execute in a reasonable amount of time. absl::Cord c; - ABSL_RAW_LOG(INFO, "Made a Cord with %zu bytes!", c.size()); c.Append(from); while (c.size() < max_size) { c.Append(c); @@ -466,8 +479,8 @@ TEST(TryFlat, SubstrInlined) { TEST(TryFlat, SubstrFlat) { absl::Cord c("longer than 15 bytes"); - c.RemovePrefix(1); - EXPECT_EQ(c.TryFlat(), "onger than 15 bytes"); + absl::Cord sub = absl::CordTestPeer::MakeSubstring(c, 1, c.size() - 1); + EXPECT_EQ(sub.TryFlat(), "onger than 15 bytes"); } TEST(TryFlat, Concat) { @@ -482,16 +495,46 @@ TEST(TryFlat, External) { TEST(TryFlat, SubstrExternal) { absl::Cord c = absl::MakeCordFromExternal("hell", [](absl::string_view) {}); - c.RemovePrefix(1); - EXPECT_EQ(c.TryFlat(), "ell"); + absl::Cord sub = absl::CordTestPeer::MakeSubstring(c, 1, c.size() - 1); + EXPECT_EQ(sub.TryFlat(), "ell"); } TEST(TryFlat, SubstrConcat) { absl::Cord c = absl::MakeFragmentedCord({"hello", " world"}); + absl::Cord sub = absl::CordTestPeer::MakeSubstring(c, 1, c.size() - 1); + EXPECT_EQ(sub.TryFlat(), absl::nullopt); c.RemovePrefix(1); EXPECT_EQ(c.TryFlat(), absl::nullopt); } +TEST(TryFlat, CommonlyAssumedInvariants) { + // The behavior tested below is not part of the API contract of Cord, but it's + // something we intend to be true in our current implementation. This test + // exists to detect and prevent accidental breakage of the implementation. + absl::string_view fragments[] = {"A fragmented test", + " cord", + " to test subcords", + " of ", + "a", + " cord for", + " each chunk " + "returned by the ", + "iterator"}; + absl::Cord c = absl::MakeFragmentedCord(fragments); + int fragment = 0; + int offset = 0; + absl::Cord::CharIterator itc = c.char_begin(); + for (absl::string_view sv : c.Chunks()) { + absl::string_view expected = fragments[fragment]; + absl::Cord subcord1 = c.Subcord(offset, sv.length()); + absl::Cord subcord2 = absl::Cord::AdvanceAndRead(&itc, sv.size()); + EXPECT_EQ(subcord1.TryFlat(), expected); + EXPECT_EQ(subcord2.TryFlat(), expected); + ++fragment; + offset += sv.length(); + } +} + static bool IsFlat(const absl::Cord& c) { return c.chunk_begin() == c.chunk_end() || ++c.chunk_begin() == c.chunk_end(); } @@ -1274,6 +1317,26 @@ TEST(Cord, Concat_Append) { EXPECT_EQ(s2.size(), size + 1); } +TEST(Cord, DiabolicalGrowth) { + // This test exercises a diabolical Append(<one char>) on a cord, making the + // cord shared before each Append call resulting in a terribly fragmented + // resulting cord. + // TODO(b/183983616): Apply some minimum compaction when copying a shared + // source cord into a mutable copy for updates in CordRepRing. + RandomEngine rng(testing::GTEST_FLAG(random_seed)); + const std::string expected = RandomLowercaseString(&rng, 5000); + absl::Cord cord; + for (char c : expected) { + absl::Cord shared(cord); + cord.Append(absl::string_view(&c, 1)); + } + std::string value; + absl::CopyCordToString(cord, &value); + EXPECT_EQ(value, expected); + ABSL_RAW_LOG(INFO, "Diabolical size allocated = %zu", + cord.EstimatedMemoryUsage()); +} + TEST(MakeFragmentedCord, MakeFragmentedCordFromInitializerList) { absl::Cord fragmented = absl::MakeFragmentedCord({"A ", "fragmented ", "Cord"}); |