reuse base binary converter with templating

python/pyarrow/src/arrow/python/python_to_arrow.cc

@@ -697,56 +697,23 @@ class PyPrimitiveConverter<T, enable_if_t<std::is_same<T, FixedSizeBinaryType>::
   PyBytesView view_;
 };
 
-template <typename T>
-class PyPrimitiveConverter<T, enable_if_base_binary<T>>
-    : public PrimitiveConverter<T, PyConverter> {
- public:
-  using OffsetType = typename T::offset_type;
-
-  Status Append(PyObject* value) override {
-    if (PyValue::IsNull(this->options_, value)) {
-      this->primitive_builder_->UnsafeAppendNull();
-    } else if (arrow::py::is_scalar(value)) {
-      ARROW_ASSIGN_OR_RAISE(std::shared_ptr<Scalar> scalar,
-                            arrow::py::unwrap_scalar(value));
-      ARROW_RETURN_NOT_OK(this->primitive_builder_->AppendScalar(*scalar));
-    } else {
-      ARROW_RETURN_NOT_OK(
-          PyValue::Convert(this->primitive_type_, this->options_, value, view_));
-      if (!view_.is_utf8) {
-        // observed binary value
-        observed_binary_ = true;
-      }
-      // Since we don't know the varying length input size in advance, we need to
-      // reserve space in the value builder one by one. ReserveData raises CapacityError
-      // if the value would not fit into the array.
-      ARROW_RETURN_NOT_OK(this->primitive_builder_->ReserveData(view_.size));
-      this->primitive_builder_->UnsafeAppend(view_.bytes,
-                                             static_cast<OffsetType>(view_.size));
-    }
-    return Status::OK();
-  }
-
-  Result<std::shared_ptr<Array>> ToArray() override {
-    ARROW_ASSIGN_OR_RAISE(auto array, (PrimitiveConverter<T, PyConverter>::ToArray()));
-    if (observed_binary_) {
-      // if we saw any non-unicode, cast results to BinaryArray
-      auto binary_type = TypeTraits<typename T::PhysicalType>::type_singleton();
-      return array->View(binary_type);
-    } else {
-      return array;
-    }
-  }
+template <typename T, typename Enable = void>
+struct OffsetTypeTrait {
+  using type = typename T::offset_type;
+};
 
- protected:
-  PyBytesView view_;
-  bool observed_binary_ = false;
+template <typename T>
+struct OffsetTypeTrait<T, enable_if_binary_view_like<T>> {
+  using type = int64_t;
 };
 
 template <typename T>
-class PyPrimitiveConverter<T, enable_if_t<is_binary_view_like_type<T>::value>>
+class PyPrimitiveConverter<
+    T, enable_if_t<is_base_binary_type<T>::value || is_binary_view_like_type<T>::value>>
     : public PrimitiveConverter<T, PyConverter> {
  public:
+  using OffsetType = typename OffsetTypeTrait<T>::type;
+
   Status Append(PyObject* value) override {
     if (PyValue::IsNull(this->options_, value)) {
       this->primitive_builder_->UnsafeAppendNull();
@@ -766,7 +733,7 @@ class PyPrimitiveConverter<T, enable_if_t<is_binary_view_like_type<T>::value>>
       // if the value would not fit into the array.
       ARROW_RETURN_NOT_OK(this->primitive_builder_->ReserveData(view_.size));
       this->primitive_builder_->UnsafeAppend(view_.bytes,
-                                             static_cast<int64_t>(view_.size));
+                                             static_cast<OffsetType>(view_.size));
     }
     return Status::OK();
   }