Method OpenOutputStream

cpp/src/arrow/filesystem/mockfs.cc:384–415

  }

  Result<std::shared_ptr<io::OutputStream>> OpenOutputStream(
      const std::string& path, bool append,
      const std::shared_ptr<const KeyValueMetadata>& metadata) {
    ARROW_RETURN_NOT_OK(internal::AssertNoTrailingSlash(path));
    auto parts = SplitAbstractPath(path);
    RETURN_NOT_OK(ValidateAbstractPathParts(parts));

    Entry* parent = FindParent(parts);
    if (parent == nullptr || !parent->is_dir()) {
      return PathNotFound(path);
    }
    // Find the file in the parent dir, or create it
    const auto& name = parts.back();
    Entry* child = parent->as_dir().Find(name);
    File* file;
    if (child == nullptr) {
      child = new Entry(File(current_time, name));
      parent->as_dir().AssignEntry(name, std::unique_ptr<Entry>(child));
      file = &child->as_file();
    } else if (child->is_file()) {
      file = &child->as_file();
      file->mtime = current_time;
    } else {
      return NotAFile(path);
    }
    file->metadata = metadata;
    auto ptr = std::make_shared<MockFSOutputStream>(file, pool);
    if (append && file->data) {
      RETURN_NOT_OK(ptr->Write(file->data->data(), file->data->size()));
    }
    return ptr;
  }

  Result<std::shared_ptr<io::BufferReader>> OpenInputReader(const std::string& path) {
    ARROW_RETURN_NOT_OK(internal::AssertNoTrailingSlash(path));