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Diffstat (limited to 'table/table_test.cc')
-rw-r--r-- | table/table_test.cc | 830 |
1 files changed, 830 insertions, 0 deletions
diff --git a/table/table_test.cc b/table/table_test.cc new file mode 100644 index 0000000..311839e --- /dev/null +++ b/table/table_test.cc @@ -0,0 +1,830 @@ +// Copyright (c) 2011 The LevelDB Authors. All rights reserved. +// Use of this source code is governed by a BSD-style license that can be +// found in the LICENSE file. See the AUTHORS file for names of contributors. + +#include "leveldb/table.h" + +#include <map> +#include <string> + +#include "gtest/gtest.h" +#include "db/dbformat.h" +#include "db/memtable.h" +#include "db/write_batch_internal.h" +#include "leveldb/db.h" +#include "leveldb/env.h" +#include "leveldb/iterator.h" +#include "leveldb/table_builder.h" +#include "table/block.h" +#include "table/block_builder.h" +#include "table/format.h" +#include "util/random.h" +#include "util/testutil.h" + +namespace leveldb { + +// Return reverse of "key". +// Used to test non-lexicographic comparators. +static std::string Reverse(const Slice& key) { + std::string str(key.ToString()); + std::string rev(""); + for (std::string::reverse_iterator rit = str.rbegin(); rit != str.rend(); + ++rit) { + rev.push_back(*rit); + } + return rev; +} + +namespace { +class ReverseKeyComparator : public Comparator { + public: + const char* Name() const override { + return "leveldb.ReverseBytewiseComparator"; + } + + int Compare(const Slice& a, const Slice& b) const override { + return BytewiseComparator()->Compare(Reverse(a), Reverse(b)); + } + + void FindShortestSeparator(std::string* start, + const Slice& limit) const override { + std::string s = Reverse(*start); + std::string l = Reverse(limit); + BytewiseComparator()->FindShortestSeparator(&s, l); + *start = Reverse(s); + } + + void FindShortSuccessor(std::string* key) const override { + std::string s = Reverse(*key); + BytewiseComparator()->FindShortSuccessor(&s); + *key = Reverse(s); + } +}; +} // namespace +static ReverseKeyComparator reverse_key_comparator; + +static void Increment(const Comparator* cmp, std::string* key) { + if (cmp == BytewiseComparator()) { + key->push_back('\0'); + } else { + assert(cmp == &reverse_key_comparator); + std::string rev = Reverse(*key); + rev.push_back('\0'); + *key = Reverse(rev); + } +} + +// An STL comparator that uses a Comparator +namespace { +struct STLLessThan { + const Comparator* cmp; + + STLLessThan() : cmp(BytewiseComparator()) {} + STLLessThan(const Comparator* c) : cmp(c) {} + bool operator()(const std::string& a, const std::string& b) const { + return cmp->Compare(Slice(a), Slice(b)) < 0; + } +}; +} // namespace + +class StringSink : public WritableFile { + public: + ~StringSink() override = default; + + const std::string& contents() const { return contents_; } + + Status Close() override { return Status::OK(); } + Status Flush() override { return Status::OK(); } + Status Sync() override { return Status::OK(); } + + Status Append(const Slice& data) override { + contents_.append(data.data(), data.size()); + return Status::OK(); + } + + private: + std::string contents_; +}; + +class StringSource : public RandomAccessFile { + public: + StringSource(const Slice& contents) + : contents_(contents.data(), contents.size()) {} + + ~StringSource() override = default; + + uint64_t Size() const { return contents_.size(); } + + Status Read(uint64_t offset, size_t n, Slice* result, + char* scratch) const override { + if (offset >= contents_.size()) { + return Status::InvalidArgument("invalid Read offset"); + } + if (offset + n > contents_.size()) { + n = contents_.size() - offset; + } + std::memcpy(scratch, &contents_[offset], n); + *result = Slice(scratch, n); + return Status::OK(); + } + + private: + std::string contents_; +}; + +typedef std::map<std::string, std::string, STLLessThan> KVMap; + +// Helper class for tests to unify the interface between +// BlockBuilder/TableBuilder and Block/Table. +class Constructor { + public: + explicit Constructor(const Comparator* cmp) : data_(STLLessThan(cmp)) {} + virtual ~Constructor() = default; + + void Add(const std::string& key, const Slice& value) { + data_[key] = value.ToString(); + } + + // Finish constructing the data structure with all the keys that have + // been added so far. Returns the keys in sorted order in "*keys" + // and stores the key/value pairs in "*kvmap" + void Finish(const Options& options, std::vector<std::string>* keys, + KVMap* kvmap) { + *kvmap = data_; + keys->clear(); + for (const auto& kvp : data_) { + keys->push_back(kvp.first); + } + data_.clear(); + Status s = FinishImpl(options, *kvmap); + ASSERT_TRUE(s.ok()) << s.ToString(); + } + + // Construct the data structure from the data in "data" + virtual Status FinishImpl(const Options& options, const KVMap& data) = 0; + + virtual Iterator* NewIterator() const = 0; + + const KVMap& data() const { return data_; } + + virtual DB* db() const { return nullptr; } // Overridden in DBConstructor + + private: + KVMap data_; +}; + +class BlockConstructor : public Constructor { + public: + explicit BlockConstructor(const Comparator* cmp) + : Constructor(cmp), comparator_(cmp), block_(nullptr) {} + ~BlockConstructor() override { delete block_; } + Status FinishImpl(const Options& options, const KVMap& data) override { + delete block_; + block_ = nullptr; + BlockBuilder builder(&options); + + for (const auto& kvp : data) { + builder.Add(kvp.first, kvp.second); + } + // Open the block + data_ = builder.Finish().ToString(); + BlockContents contents; + contents.data = data_; + contents.cachable = false; + contents.heap_allocated = false; + block_ = new Block(contents); + return Status::OK(); + } + Iterator* NewIterator() const override { + return block_->NewIterator(comparator_); + } + + private: + const Comparator* const comparator_; + std::string data_; + Block* block_; + + BlockConstructor(); +}; + +class TableConstructor : public Constructor { + public: + TableConstructor(const Comparator* cmp) + : Constructor(cmp), source_(nullptr), table_(nullptr) {} + ~TableConstructor() override { Reset(); } + Status FinishImpl(const Options& options, const KVMap& data) override { + Reset(); + StringSink sink; + TableBuilder builder(options, &sink); + + for (const auto& kvp : data) { + builder.Add(kvp.first, kvp.second); + EXPECT_LEVELDB_OK(builder.status()); + } + Status s = builder.Finish(); + EXPECT_LEVELDB_OK(s); + + EXPECT_EQ(sink.contents().size(), builder.FileSize()); + + // Open the table + source_ = new StringSource(sink.contents()); + Options table_options; + table_options.comparator = options.comparator; + return Table::Open(table_options, source_, sink.contents().size(), &table_); + } + + Iterator* NewIterator() const override { + return table_->NewIterator(ReadOptions()); + } + + uint64_t ApproximateOffsetOf(const Slice& key) const { + return table_->ApproximateOffsetOf(key); + } + + private: + void Reset() { + delete table_; + delete source_; + table_ = nullptr; + source_ = nullptr; + } + + StringSource* source_; + Table* table_; + + TableConstructor(); +}; + +// A helper class that converts internal format keys into user keys +class KeyConvertingIterator : public Iterator { + public: + explicit KeyConvertingIterator(Iterator* iter) : iter_(iter) {} + + KeyConvertingIterator(const KeyConvertingIterator&) = delete; + KeyConvertingIterator& operator=(const KeyConvertingIterator&) = delete; + + ~KeyConvertingIterator() override { delete iter_; } + + bool Valid() const override { return iter_->Valid(); } + void Seek(const Slice& target) override { + ParsedInternalKey ikey(target, kMaxSequenceNumber, kTypeValue); + std::string encoded; + AppendInternalKey(&encoded, ikey); + iter_->Seek(encoded); + } + void SeekToFirst() override { iter_->SeekToFirst(); } + void SeekToLast() override { iter_->SeekToLast(); } + void Next() override { iter_->Next(); } + void Prev() override { iter_->Prev(); } + + Slice key() const override { + assert(Valid()); + ParsedInternalKey key; + if (!ParseInternalKey(iter_->key(), &key)) { + status_ = Status::Corruption("malformed internal key"); + return Slice("corrupted key"); + } + return key.user_key; + } + + Slice value() const override { return iter_->value(); } + Status status() const override { + return status_.ok() ? iter_->status() : status_; + } + + private: + mutable Status status_; + Iterator* iter_; +}; + +class MemTableConstructor : public Constructor { + public: + explicit MemTableConstructor(const Comparator* cmp) + : Constructor(cmp), internal_comparator_(cmp) { + memtable_ = new MemTable(internal_comparator_); + memtable_->Ref(); + } + ~MemTableConstructor() override { memtable_->Unref(); } + Status FinishImpl(const Options& options, const KVMap& data) override { + memtable_->Unref(); + memtable_ = new MemTable(internal_comparator_); + memtable_->Ref(); + int seq = 1; + for (const auto& kvp : data) { + memtable_->Add(seq, kTypeValue, kvp.first, kvp.second); + seq++; + } + return Status::OK(); + } + Iterator* NewIterator() const override { + return new KeyConvertingIterator(memtable_->NewIterator()); + } + + private: + const InternalKeyComparator internal_comparator_; + MemTable* memtable_; +}; + +class DBConstructor : public Constructor { + public: + explicit DBConstructor(const Comparator* cmp) + : Constructor(cmp), comparator_(cmp) { + db_ = nullptr; + NewDB(); + } + ~DBConstructor() override { delete db_; } + Status FinishImpl(const Options& options, const KVMap& data) override { + delete db_; + db_ = nullptr; + NewDB(); + for (const auto& kvp : data) { + WriteBatch batch; + batch.Put(kvp.first, kvp.second); + EXPECT_TRUE(db_->Write(WriteOptions(), &batch).ok()); + } + return Status::OK(); + } + Iterator* NewIterator() const override { + return db_->NewIterator(ReadOptions()); + } + + DB* db() const override { return db_; } + + private: + void NewDB() { + std::string name = testing::TempDir() + "table_testdb"; + + Options options; + options.comparator = comparator_; + Status status = DestroyDB(name, options); + ASSERT_TRUE(status.ok()) << status.ToString(); + + options.create_if_missing = true; + options.error_if_exists = true; + options.write_buffer_size = 10000; // Something small to force merging + status = DB::Open(options, name, &db_); + ASSERT_TRUE(status.ok()) << status.ToString(); + } + + const Comparator* const comparator_; + DB* db_; +}; + +enum TestType { TABLE_TEST, BLOCK_TEST, MEMTABLE_TEST, DB_TEST }; + +struct TestArgs { + TestType type; + bool reverse_compare; + int restart_interval; +}; + +static const TestArgs kTestArgList[] = { + {TABLE_TEST, false, 16}, + {TABLE_TEST, false, 1}, + {TABLE_TEST, false, 1024}, + {TABLE_TEST, true, 16}, + {TABLE_TEST, true, 1}, + {TABLE_TEST, true, 1024}, + + {BLOCK_TEST, false, 16}, + {BLOCK_TEST, false, 1}, + {BLOCK_TEST, false, 1024}, + {BLOCK_TEST, true, 16}, + {BLOCK_TEST, true, 1}, + {BLOCK_TEST, true, 1024}, + + // Restart interval does not matter for memtables + {MEMTABLE_TEST, false, 16}, + {MEMTABLE_TEST, true, 16}, + + // Do not bother with restart interval variations for DB + {DB_TEST, false, 16}, + {DB_TEST, true, 16}, +}; +static const int kNumTestArgs = sizeof(kTestArgList) / sizeof(kTestArgList[0]); + +class Harness : public testing::Test { + public: + Harness() : constructor_(nullptr) {} + + void Init(const TestArgs& args) { + delete constructor_; + constructor_ = nullptr; + options_ = Options(); + + options_.block_restart_interval = args.restart_interval; + // Use shorter block size for tests to exercise block boundary + // conditions more. + options_.block_size = 256; + if (args.reverse_compare) { + options_.comparator = &reverse_key_comparator; + } + switch (args.type) { + case TABLE_TEST: + constructor_ = new TableConstructor(options_.comparator); + break; + case BLOCK_TEST: + constructor_ = new BlockConstructor(options_.comparator); + break; + case MEMTABLE_TEST: + constructor_ = new MemTableConstructor(options_.comparator); + break; + case DB_TEST: + constructor_ = new DBConstructor(options_.comparator); + break; + } + } + + ~Harness() { delete constructor_; } + + void Add(const std::string& key, const std::string& value) { + constructor_->Add(key, value); + } + + void Test(Random* rnd) { + std::vector<std::string> keys; + KVMap data; + constructor_->Finish(options_, &keys, &data); + + TestForwardScan(keys, data); + TestBackwardScan(keys, data); + TestRandomAccess(rnd, keys, data); + } + + void TestForwardScan(const std::vector<std::string>& keys, + const KVMap& data) { + Iterator* iter = constructor_->NewIterator(); + ASSERT_TRUE(!iter->Valid()); + iter->SeekToFirst(); + for (KVMap::const_iterator model_iter = data.begin(); + model_iter != data.end(); ++model_iter) { + ASSERT_EQ(ToString(data, model_iter), ToString(iter)); + iter->Next(); + } + ASSERT_TRUE(!iter->Valid()); + delete iter; + } + + void TestBackwardScan(const std::vector<std::string>& keys, + const KVMap& data) { + Iterator* iter = constructor_->NewIterator(); + ASSERT_TRUE(!iter->Valid()); + iter->SeekToLast(); + for (KVMap::const_reverse_iterator model_iter = data.rbegin(); + model_iter != data.rend(); ++model_iter) { + ASSERT_EQ(ToString(data, model_iter), ToString(iter)); + iter->Prev(); + } + ASSERT_TRUE(!iter->Valid()); + delete iter; + } + + void TestRandomAccess(Random* rnd, const std::vector<std::string>& keys, + const KVMap& data) { + static const bool kVerbose = false; + Iterator* iter = constructor_->NewIterator(); + ASSERT_TRUE(!iter->Valid()); + KVMap::const_iterator model_iter = data.begin(); + if (kVerbose) std::fprintf(stderr, "---\n"); + for (int i = 0; i < 200; i++) { + const int toss = rnd->Uniform(5); + switch (toss) { + case 0: { + if (iter->Valid()) { + if (kVerbose) std::fprintf(stderr, "Next\n"); + iter->Next(); + ++model_iter; + ASSERT_EQ(ToString(data, model_iter), ToString(iter)); + } + break; + } + + case 1: { + if (kVerbose) std::fprintf(stderr, "SeekToFirst\n"); + iter->SeekToFirst(); + model_iter = data.begin(); + ASSERT_EQ(ToString(data, model_iter), ToString(iter)); + break; + } + + case 2: { + std::string key = PickRandomKey(rnd, keys); + model_iter = data.lower_bound(key); + if (kVerbose) + std::fprintf(stderr, "Seek '%s'\n", EscapeString(key).c_str()); + iter->Seek(Slice(key)); + ASSERT_EQ(ToString(data, model_iter), ToString(iter)); + break; + } + + case 3: { + if (iter->Valid()) { + if (kVerbose) std::fprintf(stderr, "Prev\n"); + iter->Prev(); + if (model_iter == data.begin()) { + model_iter = data.end(); // Wrap around to invalid value + } else { + --model_iter; + } + ASSERT_EQ(ToString(data, model_iter), ToString(iter)); + } + break; + } + + case 4: { + if (kVerbose) std::fprintf(stderr, "SeekToLast\n"); + iter->SeekToLast(); + if (keys.empty()) { + model_iter = data.end(); + } else { + std::string last = data.rbegin()->first; + model_iter = data.lower_bound(last); + } + ASSERT_EQ(ToString(data, model_iter), ToString(iter)); + break; + } + } + } + delete iter; + } + + std::string ToString(const KVMap& data, const KVMap::const_iterator& it) { + if (it == data.end()) { + return "END"; + } else { + return "'" + it->first + "->" + it->second + "'"; + } + } + + std::string ToString(const KVMap& data, + const KVMap::const_reverse_iterator& it) { + if (it == data.rend()) { + return "END"; + } else { + return "'" + it->first + "->" + it->second + "'"; + } + } + + std::string ToString(const Iterator* it) { + if (!it->Valid()) { + return "END"; + } else { + return "'" + it->key().ToString() + "->" + it->value().ToString() + "'"; + } + } + + std::string PickRandomKey(Random* rnd, const std::vector<std::string>& keys) { + if (keys.empty()) { + return "foo"; + } else { + const int index = rnd->Uniform(keys.size()); + std::string result = keys[index]; + switch (rnd->Uniform(3)) { + case 0: + // Return an existing key + break; + case 1: { + // Attempt to return something smaller than an existing key + if (!result.empty() && result[result.size() - 1] > '\0') { + result[result.size() - 1]--; + } + break; + } + case 2: { + // Return something larger than an existing key + Increment(options_.comparator, &result); + break; + } + } + return result; + } + } + + // Returns nullptr if not running against a DB + DB* db() const { return constructor_->db(); } + + private: + Options options_; + Constructor* constructor_; +}; + +// Test empty table/block. +TEST_F(Harness, Empty) { + for (int i = 0; i < kNumTestArgs; i++) { + Init(kTestArgList[i]); + Random rnd(test::RandomSeed() + 1); + Test(&rnd); + } +} + +// Special test for a block with no restart entries. The C++ leveldb +// code never generates such blocks, but the Java version of leveldb +// seems to. +TEST_F(Harness, ZeroRestartPointsInBlock) { + char data[sizeof(uint32_t)]; + memset(data, 0, sizeof(data)); + BlockContents contents; + contents.data = Slice(data, sizeof(data)); + contents.cachable = false; + contents.heap_allocated = false; + Block block(contents); + Iterator* iter = block.NewIterator(BytewiseComparator()); + iter->SeekToFirst(); + ASSERT_TRUE(!iter->Valid()); + iter->SeekToLast(); + ASSERT_TRUE(!iter->Valid()); + iter->Seek("foo"); + ASSERT_TRUE(!iter->Valid()); + delete iter; +} + +// Test the empty key +TEST_F(Harness, SimpleEmptyKey) { + for (int i = 0; i < kNumTestArgs; i++) { + Init(kTestArgList[i]); + Random rnd(test::RandomSeed() + 1); + Add("", "v"); + Test(&rnd); + } +} + +TEST_F(Harness, SimpleSingle) { + for (int i = 0; i < kNumTestArgs; i++) { + Init(kTestArgList[i]); + Random rnd(test::RandomSeed() + 2); + Add("abc", "v"); + Test(&rnd); + } +} + +TEST_F(Harness, SimpleMulti) { + for (int i = 0; i < kNumTestArgs; i++) { + Init(kTestArgList[i]); + Random rnd(test::RandomSeed() + 3); + Add("abc", "v"); + Add("abcd", "v"); + Add("ac", "v2"); + Test(&rnd); + } +} + +TEST_F(Harness, SimpleSpecialKey) { + for (int i = 0; i < kNumTestArgs; i++) { + Init(kTestArgList[i]); + Random rnd(test::RandomSeed() + 4); + Add("\xff\xff", "v3"); + Test(&rnd); + } +} + +TEST_F(Harness, Randomized) { + for (int i = 0; i < kNumTestArgs; i++) { + Init(kTestArgList[i]); + Random rnd(test::RandomSeed() + 5); + for (int num_entries = 0; num_entries < 2000; + num_entries += (num_entries < 50 ? 1 : 200)) { + if ((num_entries % 10) == 0) { + std::fprintf(stderr, "case %d of %d: num_entries = %d\n", (i + 1), + int(kNumTestArgs), num_entries); + } + for (int e = 0; e < num_entries; e++) { + std::string v; + Add(test::RandomKey(&rnd, rnd.Skewed(4)), + test::RandomString(&rnd, rnd.Skewed(5), &v).ToString()); + } + Test(&rnd); + } + } +} + +TEST_F(Harness, RandomizedLongDB) { + Random rnd(test::RandomSeed()); + TestArgs args = {DB_TEST, false, 16}; + Init(args); + int num_entries = 100000; + for (int e = 0; e < num_entries; e++) { + std::string v; + Add(test::RandomKey(&rnd, rnd.Skewed(4)), + test::RandomString(&rnd, rnd.Skewed(5), &v).ToString()); + } + Test(&rnd); + + // We must have created enough data to force merging + int files = 0; + for (int level = 0; level < config::kNumLevels; level++) { + std::string value; + char name[100]; + std::snprintf(name, sizeof(name), "leveldb.num-files-at-level%d", level); + ASSERT_TRUE(db()->GetProperty(name, &value)); + files += atoi(value.c_str()); + } + ASSERT_GT(files, 0); +} + +TEST(MemTableTest, Simple) { + InternalKeyComparator cmp(BytewiseComparator()); + MemTable* memtable = new MemTable(cmp); + memtable->Ref(); + WriteBatch batch; + WriteBatchInternal::SetSequence(&batch, 100); + batch.Put(std::string("k1"), std::string("v1")); + batch.Put(std::string("k2"), std::string("v2")); + batch.Put(std::string("k3"), std::string("v3")); + batch.Put(std::string("largekey"), std::string("vlarge")); + ASSERT_TRUE(WriteBatchInternal::InsertInto(&batch, memtable).ok()); + + Iterator* iter = memtable->NewIterator(); + iter->SeekToFirst(); + while (iter->Valid()) { + std::fprintf(stderr, "key: '%s' -> '%s'\n", iter->key().ToString().c_str(), + iter->value().ToString().c_str()); + iter->Next(); + } + + delete iter; + memtable->Unref(); +} + +static bool Between(uint64_t val, uint64_t low, uint64_t high) { + bool result = (val >= low) && (val <= high); + if (!result) { + std::fprintf(stderr, "Value %llu is not in range [%llu, %llu]\n", + (unsigned long long)(val), (unsigned long long)(low), + (unsigned long long)(high)); + } + return result; +} + +TEST(TableTest, ApproximateOffsetOfPlain) { + TableConstructor c(BytewiseComparator()); + c.Add("k01", "hello"); + c.Add("k02", "hello2"); + c.Add("k03", std::string(10000, 'x')); + c.Add("k04", std::string(200000, 'x')); + c.Add("k05", std::string(300000, 'x')); + c.Add("k06", "hello3"); + c.Add("k07", std::string(100000, 'x')); + std::vector<std::string> keys; + KVMap kvmap; + Options options; + options.block_size = 1024; + options.compression = kNoCompression; + c.Finish(options, &keys, &kvmap); + + ASSERT_TRUE(Between(c.ApproximateOffsetOf("abc"), 0, 0)); + ASSERT_TRUE(Between(c.ApproximateOffsetOf("k01"), 0, 0)); + ASSERT_TRUE(Between(c.ApproximateOffsetOf("k01a"), 0, 0)); + ASSERT_TRUE(Between(c.ApproximateOffsetOf("k02"), 0, 0)); + ASSERT_TRUE(Between(c.ApproximateOffsetOf("k03"), 0, 0)); + ASSERT_TRUE(Between(c.ApproximateOffsetOf("k04"), 10000, 11000)); + ASSERT_TRUE(Between(c.ApproximateOffsetOf("k04a"), 210000, 211000)); + ASSERT_TRUE(Between(c.ApproximateOffsetOf("k05"), 210000, 211000)); + ASSERT_TRUE(Between(c.ApproximateOffsetOf("k06"), 510000, 511000)); + ASSERT_TRUE(Between(c.ApproximateOffsetOf("k07"), 510000, 511000)); + ASSERT_TRUE(Between(c.ApproximateOffsetOf("xyz"), 610000, 612000)); +} + +static bool SnappyCompressionSupported() { + std::string out; + Slice in = "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa"; + return port::Snappy_Compress(in.data(), in.size(), &out); +} + +TEST(TableTest, ApproximateOffsetOfCompressed) { + if (!SnappyCompressionSupported()) { + std::fprintf(stderr, "skipping compression tests\n"); + return; + } + + Random rnd(301); + TableConstructor c(BytewiseComparator()); + std::string tmp; + c.Add("k01", "hello"); + c.Add("k02", test::CompressibleString(&rnd, 0.25, 10000, &tmp)); + c.Add("k03", "hello3"); + c.Add("k04", test::CompressibleString(&rnd, 0.25, 10000, &tmp)); + std::vector<std::string> keys; + KVMap kvmap; + Options options; + options.block_size = 1024; + options.compression = kSnappyCompression; + c.Finish(options, &keys, &kvmap); + + // Expected upper and lower bounds of space used by compressible strings. + static const int kSlop = 1000; // Compressor effectiveness varies. + const int expected = 2500; // 10000 * compression ratio (0.25) + const int min_z = expected - kSlop; + const int max_z = expected + kSlop; + + ASSERT_TRUE(Between(c.ApproximateOffsetOf("abc"), 0, kSlop)); + ASSERT_TRUE(Between(c.ApproximateOffsetOf("k01"), 0, kSlop)); + ASSERT_TRUE(Between(c.ApproximateOffsetOf("k02"), 0, kSlop)); + // Have now emitted a large compressible string, so adjust expected offset. + ASSERT_TRUE(Between(c.ApproximateOffsetOf("k03"), min_z, max_z)); + ASSERT_TRUE(Between(c.ApproximateOffsetOf("k04"), min_z, max_z)); + // Have now emitted two large compressible strings, so adjust expected offset. + ASSERT_TRUE(Between(c.ApproximateOffsetOf("xyz"), 2 * min_z, 2 * max_z)); +} + +} // namespace leveldb + |