text: #include "tensorflow/core/public/env.h"
  
  #include "tensorflow/core/lib/io/path.h"
  #include "tensorflow/core/lib/strings/strcat.h"
  #include "tensorflow/core/platform/test.h"
  #include <gtest/gtest.h>
  
  namespace tensorflow {
  
  struct EnvTest {};
  
  TEST(EnvTest, ReadFileToString) {
    Env* env = Env::Default();
    const string dir = testing::TmpDir();
    for (const int length : {0, 1, 1212, 2553, 4928, 8196, 9000}) {
      const string filename = io::JoinPath(dir, strings::StrCat("file", length));
  
      // Write a file with the given length
      string input(length, 0);
      for (int i = 0; i < length; i++) input[i] = i;
      WriteStringToFile(env, filename, input);
  
      // Read the file back and check equality
      string output;
      TF_CHECK_OK(ReadFileToString(env, filename, &output));
      CHECK_EQ(length, output.size());
      CHECK_EQ(input, output);
    }
  }
  
  }  // namespace tensorflow
  