cpp/src/arrow/compute/kernels/scalar_cast_boolean.cc

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// to you under the Apache License, Version 2.0 (the
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//
//   http://www.apache.org/licenses/LICENSE-2.0
//
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// specific language governing permissions and limitations
// under the License.

// Cast types to boolean

#include "arrow/array/builder_primitive.h"
#include "arrow/compute/kernels/common.h"
#include "arrow/compute/kernels/scalar_cast_internal.h"
#include "arrow/util/value_parsing.h"

namespace arrow {

using internal::ParseValue;

namespace compute {
namespace internal {

struct IsNonZero {
  template <typename OutValue, typename Arg0Value>
  static OutValue Call(KernelContext*, Arg0Value val, Status*) {
    return val != 0;
  }
};

struct ParseBooleanString {
  template <typename OutValue, typename Arg0Value>
  static OutValue Call(KernelContext*, Arg0Value val, Status* st) {
    bool result = false;
    if (ARROW_PREDICT_FALSE(!ParseValue<BooleanType>(val.data(), val.size(), &result))) {
      *st = Status::Invalid("Failed to parse value: ", val);
    }
    return result;
  }
};

std::vector<std::shared_ptr<CastFunction>> GetBooleanCasts() {
  auto func = std::make_shared<CastFunction>("cast_boolean", Type::BOOL);
  AddCommonCasts(Type::BOOL, boolean(), func.get());
  AddZeroCopyCast(Type::BOOL, boolean(), boolean(), func.get());

  for (const auto& ty : NumericTypes()) {
    ArrayKernelExec exec =
        GenerateNumeric<applicator::ScalarUnary, BooleanType, IsNonZero>(*ty);
    DCHECK_OK(func->AddKernel(ty->id(), {ty}, boolean(), exec));
  }
  for (const auto& ty : BaseBinaryTypes()) {
    ArrayKernelExec exec = GenerateVarBinaryBase<applicator::ScalarUnaryNotNull,
                                                 BooleanType, ParseBooleanString>(*ty);
    DCHECK_OK(func->AddKernel(ty->id(), {ty}, boolean(), exec));
  }
  return {func};
}

}  // namespace internal
}  // namespace compute
}  // namespace arrow