tesseract/unittest/unichar_test.cc

// (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 "include_gunit.h"
#include "gmock/gmock.h"                // for testing::ElementsAreArray
#include <tesseract/unichar.h>

using tesseract::char32;
using tesseract::UNICHAR;

namespace {

TEST(UnicharTest, Conversion) {
  // This test verifies that Unichar::UTF8ToUTF32 and Unichar::UTF32ToUTF8
  // show the required conversion properties.
  // Test for round-trip utf8-32-8 for 1, 2, 3 and 4 byte codes.
  const char* kUTF8Src = "a\u05d0\u0ca4\U0002a714";
  const std::vector<char32> kUTF32Src = {'a', 0x5d0, 0xca4, 0x2a714};
  // Check for round-trip conversion.
  std::vector<char32> utf32 = UNICHAR::UTF8ToUTF32(kUTF8Src);
  EXPECT_THAT(utf32, testing::ElementsAreArray(kUTF32Src));
  std::string utf8 = UNICHAR::UTF32ToUTF8(utf32);
  EXPECT_STREQ(kUTF8Src, utf8.c_str());
}

TEST(UnicharTest, InvalidText) {
  // This test verifies that Unichar correctly deals with invalid text.
  const char* kInvalidUTF8 = "a b\200d string";
  const std::vector<char32> kInvalidUTF32 = {'a', ' ', 0x200000, 'x'};
  // Invalid utf8 produces an empty vector.
  std::vector<char32> utf32 = UNICHAR::UTF8ToUTF32(kInvalidUTF8);
  EXPECT_TRUE(utf32.empty());
  // Invalid utf32 produces an empty string.
  std::string utf8 = UNICHAR::UTF32ToUTF8(kInvalidUTF32);
  EXPECT_TRUE(utf8.empty());
}

}  // namespace