tesseract/unittest/indexmapbidi_test.cc
Stefan Weil c4eda838aa unittest: Fix and enable indexmapbidi_test
Signed-off-by: Stefan Weil <sw@weilnetz.de>
2018-08-25 18:39:40 +02:00

117 lines
3.6 KiB
C++

// (C) Copyright 2017, Google Inc.
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
// http://www.apache.org/licenses/LICENSE-2.0
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
#include <cmath>
#include <cstdio>
#include <string>
#include "indexmapbidi.h"
#include "include_gunit.h"
using tesseract::IndexMap;
using tesseract::IndexMapBiDi;
const int kPrimeLimit = 1000;
namespace {
class IndexMapBiDiTest : public testing::Test {
public:
std::string OutputNameToPath(const std::string& name) {
return file::JoinPath(FLAGS_test_tmpdir, name);
}
// Computes primes upto kPrimeLimit, using the seive of Eratosthenes.
void ComputePrimes(IndexMapBiDi* map) {
map->Init(kPrimeLimit + 1, false);
map->SetMap(2, true);
// Set all the odds to true.
for (int i = 3; i <= kPrimeLimit; i += 2)
map->SetMap(i, true);
int factor_limit = static_cast<int>(sqrt(1.0 + kPrimeLimit));
for (int f = 3; f <= factor_limit; f += 2) {
if (map->SparseToCompact(f) >= 0) {
for (int m = 2; m * f <= kPrimeLimit; ++m)
map->SetMap(f * m, false);
}
}
map->Setup();
}
void TestPrimes(const IndexMap& map) {
// Now all primes are mapped in the sparse map to their index.
// According to Wikipedia, the 168th prime is 997, and it has compact
// index 167 because we are indexing from 0.
EXPECT_EQ(167, map.SparseToCompact(997));
EXPECT_EQ(997, map.CompactToSparse(167));
// 995, 996, 998, 999 are not prime.
EXPECT_EQ(-1, map.SparseToCompact(995));
EXPECT_EQ(-1, map.SparseToCompact(996));
EXPECT_EQ(-1, map.SparseToCompact(998));
EXPECT_EQ(-1, map.SparseToCompact(999));
// The 167th prime is 991.
EXPECT_EQ(991, map.CompactToSparse(166));
// There are 168 primes in 0..1000.
EXPECT_EQ(168, map.CompactSize());
EXPECT_EQ(kPrimeLimit + 1, map.SparseSize());
}
};
// Tests the seive of Eratosthenes as a way of testing setup.
TEST_F(IndexMapBiDiTest, Primes) {
IndexMapBiDi map;
ComputePrimes(&map);
TestPrimes(map);
// It still works if we assign it to another.
IndexMapBiDi map2;
map2.CopyFrom(map);
TestPrimes(map2);
// Or if we assign it to a base class.
IndexMap base_map;
base_map.CopyFrom(map);
TestPrimes(base_map);
// Test file i/o too.
std::string filename = OutputNameToPath("primesmap");
FILE* fp = fopen(filename.c_str(), "wb");
CHECK(fp != nullptr);
EXPECT_TRUE(map.Serialize(fp));
fclose(fp);
fp = fopen(filename.c_str(), "rb");
CHECK(fp != nullptr);
IndexMapBiDi read_map;
EXPECT_TRUE(read_map.DeSerialize(false, fp));
fclose(fp);
TestPrimes(read_map);
}
// Tests the many-to-one setup feature.
TEST_F(IndexMapBiDiTest, ManyToOne) {
// Test the example in the comment on CompleteMerges.
IndexMapBiDi map;
map.Init(13, false);
map.SetMap(2, true);
map.SetMap(4, true);
map.SetMap(7, true);
map.SetMap(9, true);
map.SetMap(11, true);
map.Setup();
map.Merge(map.SparseToCompact(2), map.SparseToCompact(9));
map.Merge(map.SparseToCompact(4), map.SparseToCompact(11));
map.CompleteMerges();
EXPECT_EQ(3, map.CompactSize());
EXPECT_EQ(13, map.SparseSize());
EXPECT_EQ(1, map.SparseToCompact(4));
EXPECT_EQ(4, map.CompactToSparse(1));
EXPECT_EQ(1, map.SparseToCompact(11));
}
} // namespace.