api.rs

// Licensed to the Apache Software Foundation (ASF) under one
// or more contributor license agreements.  See the NOTICE file
// distributed with this work for additional information
// regarding copyright ownership.  The ASF licenses this file
// to you 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.

//! Contains Row enum that is used to represent record in Rust.

use std::fmt;

use basic::{LogicalType, Type as PhysicalType};
use chrono::{Local, TimeZone};
use data_type::{ByteArray, Decimal, Int96};
use errors::{ParquetError, Result};
use num_bigint::{BigInt, Sign};
use schema::types::ColumnDescPtr;

/// Macro as a shortcut to generate 'not yet implemented' panic error.
macro_rules! nyi {
  ($column_descr:ident, $value:ident) => {{
    unimplemented!(
      "Conversion for physical type {}, logical type {}, value {:?}",
      $column_descr.physical_type(),
      $column_descr.logical_type(),
      $value
    );
  }};
}

/// `Row` represents a nested Parquet record.
#[derive(Clone, Debug, PartialEq)]
pub struct Row {
  fields: Vec<(String, Field)>,
}

impl Row {
  /// Get the number of fields in this row.
  pub fn len(&self) -> usize { self.fields.len() }
}

/// Trait for type-safe convenient access to fields within a Row.
pub trait RowAccessor {
  fn get_bool(&self, i: usize) -> Result<bool>;
  fn get_byte(&self, i: usize) -> Result<i8>;
  fn get_short(&self, i: usize) -> Result<i16>;
  fn get_int(&self, i: usize) -> Result<i32>;
  fn get_long(&self, i: usize) -> Result<i64>;
  fn get_ubyte(&self, i: usize) -> Result<u8>;
  fn get_ushort(&self, i: usize) -> Result<u16>;
  fn get_uint(&self, i: usize) -> Result<u32>;
  fn get_ulong(&self, i: usize) -> Result<u64>;
  fn get_float(&self, i: usize) -> Result<f32>;
  fn get_double(&self, i: usize) -> Result<f64>;
  fn get_timestamp(&self, i: usize) -> Result<u64>;
  fn get_decimal(&self, i: usize) -> Result<&Decimal>;
  fn get_string(&self, i: usize) -> Result<&String>;
  fn get_bytes(&self, i: usize) -> Result<&ByteArray>;
  fn get_group(&self, i: usize) -> Result<&Row>;
  fn get_list(&self, i: usize) -> Result<&List>;
  fn get_map(&self, i: usize) -> Result<&Map>;
}

/// Macro to generate type-safe get_xxx methods for primitive types,
/// e.g. `get_bool`, `get_short`.
macro_rules! row_primitive_accessor {
  ($METHOD:ident, $VARIANT:ident, $TY:ty) => {
    fn $METHOD(&self, i: usize) -> Result<$TY> {
      match self.fields[i].1 {
        Field::$VARIANT(v) => Ok(v),
        _ => Err(general_err!("Cannot access {} as {}",
          self.fields[i].1.get_type_name(), stringify!($VARIANT)))
      }
    }
  }
}

/// Macro to generate type-safe get_xxx methods for reference types,
/// e.g. `get_list`, `get_map`.
macro_rules! row_complex_accessor {
  ($METHOD:ident, $VARIANT:ident, $TY:ty) => {
    fn $METHOD(&self, i: usize) -> Result<&$TY> {
      match self.fields[i].1 {
        Field::$VARIANT(ref v) => Ok(v),
        _ => Err(general_err!("Cannot access {} as {}",
          self.fields[i].1.get_type_name(), stringify!($VARIANT)))
      }
    }
  }
}

impl RowAccessor for Row {
  row_primitive_accessor!(get_bool, Bool, bool);

  row_primitive_accessor!(get_byte, Byte, i8);

  row_primitive_accessor!(get_short, Short, i16);

  row_primitive_accessor!(get_int, Int, i32);

  row_primitive_accessor!(get_long, Long, i64);

  row_primitive_accessor!(get_ubyte, UByte, u8);

  row_primitive_accessor!(get_ushort, UShort, u16);

  row_primitive_accessor!(get_uint, UInt, u32);

  row_primitive_accessor!(get_ulong, ULong, u64);

  row_primitive_accessor!(get_float, Float, f32);

  row_primitive_accessor!(get_double, Double, f64);

  row_primitive_accessor!(get_timestamp, Timestamp, u64);

  row_complex_accessor!(get_decimal, Decimal, Decimal);

  row_complex_accessor!(get_string, Str, String);

  row_complex_accessor!(get_bytes, Bytes, ByteArray);

  row_complex_accessor!(get_group, Group, Row);

  row_complex_accessor!(get_list, ListInternal, List);

  row_complex_accessor!(get_map, MapInternal, Map);
}

/// Constructs a `Row` from the list of `fields` and returns it.
#[inline]
pub fn make_row(fields: Vec<(String, Field)>) -> Row { Row { fields } }

impl fmt::Display for Row {
  fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
    write!(f, "{{")?;
    for (i, &(ref key, ref value)) in self.fields.iter().enumerate() {
      key.fmt(f)?;
      write!(f, ": ")?;
      value.fmt(f)?;
      if i < self.fields.len() - 1 {
        write!(f, ", ")?;
      }
    }
    write!(f, "}}")
  }
}

/// `List` represents a list which contains an array of elements.
#[derive(Clone, Debug, PartialEq)]
pub struct List {
  elements: Vec<Field>,
}

impl List {
  /// Get the number of fields in this row
  pub fn len(&self) -> usize { self.elements.len() }
}

/// Constructs a `List` from the list of `fields` and returns it.
#[inline]
pub fn make_list(elements: Vec<Field>) -> List { List { elements } }

/// Trait for type-safe access of an index for a `List`.
/// Note that the get_XXX methods do not do bound checking.
pub trait ListAccessor {
  fn get_bool(&self, i: usize) -> Result<bool>;
  fn get_byte(&self, i: usize) -> Result<i8>;
  fn get_short(&self, i: usize) -> Result<i16>;
  fn get_int(&self, i: usize) -> Result<i32>;
  fn get_long(&self, i: usize) -> Result<i64>;
  fn get_ubyte(&self, i: usize) -> Result<u8>;
  fn get_ushort(&self, i: usize) -> Result<u16>;
  fn get_uint(&self, i: usize) -> Result<u32>;
  fn get_ulong(&self, i: usize) -> Result<u64>;
  fn get_float(&self, i: usize) -> Result<f32>;
  fn get_double(&self, i: usize) -> Result<f64>;
  fn get_timestamp(&self, i: usize) -> Result<u64>;
  fn get_decimal(&self, i: usize) -> Result<&Decimal>;
  fn get_string(&self, i: usize) -> Result<&String>;
  fn get_bytes(&self, i: usize) -> Result<&ByteArray>;
  fn get_group(&self, i: usize) -> Result<&Row>;
  fn get_list(&self, i: usize) -> Result<&List>;
  fn get_map(&self, i: usize) -> Result<&Map>;
}

/// Macro to generate type-safe get_xxx methods for primitive types,
/// e.g. get_bool, get_short
macro_rules! list_primitive_accessor {
  ($METHOD:ident, $VARIANT:ident, $TY:ty) => {
    fn $METHOD(&self, i: usize) -> Result<$TY> {
      match self.elements[i] {
        Field::$VARIANT(v) => Ok(v),
        _ => Err(general_err!(
          "Cannot access {} as {}",
          self.elements[i].get_type_name(), stringify!($VARIANT))
        )
      }
    }
  }
}

/// Macro to generate type-safe get_xxx methods for reference types
/// e.g. get_list, get_map
macro_rules! list_complex_accessor {
  ($METHOD:ident, $VARIANT:ident, $TY:ty) => {
    fn $METHOD(&self, i: usize) -> Result<&$TY> {
      match self.elements[i] {
        Field::$VARIANT(ref v) => Ok(v),
        _ => Err(general_err!(
          "Cannot access {} as {}",
          self.elements[i].get_type_name(), stringify!($VARIANT))
        )
      }
    }
  }
}

impl ListAccessor for List {
  list_primitive_accessor!(get_bool, Bool, bool);

  list_primitive_accessor!(get_byte, Byte, i8);

  list_primitive_accessor!(get_short, Short, i16);

  list_primitive_accessor!(get_int, Int, i32);

  list_primitive_accessor!(get_long, Long, i64);

  list_primitive_accessor!(get_ubyte, UByte, u8);

  list_primitive_accessor!(get_ushort, UShort, u16);

  list_primitive_accessor!(get_uint, UInt, u32);

  list_primitive_accessor!(get_ulong, ULong, u64);

  list_primitive_accessor!(get_float, Float, f32);

  list_primitive_accessor!(get_double, Double, f64);

  list_primitive_accessor!(get_timestamp, Timestamp, u64);

  list_complex_accessor!(get_decimal, Decimal, Decimal);

  list_complex_accessor!(get_string, Str, String);

  list_complex_accessor!(get_bytes, Bytes, ByteArray);

  list_complex_accessor!(get_group, Group, Row);

  list_complex_accessor!(get_list, ListInternal, List);

  list_complex_accessor!(get_map, MapInternal, Map);
}

/// `Map` represents a map which contains an list of key->value pairs.
#[derive(Clone, Debug, PartialEq)]
pub struct Map {
  entries: Vec<(Field, Field)>,
}

impl Map {
  /// Get the number of fields in this row
  pub fn len(&self) -> usize { self.entries.len() }
}

/// Constructs a `Map` from the list of `entries` and returns it.
#[inline]
pub fn make_map(entries: Vec<(Field, Field)>) -> Map { Map { entries } }

/// Trait for type-safe access of an index for a `Map`
pub trait MapAccessor {
  fn get_keys<'a>(&'a self) -> Box<ListAccessor + 'a>;
  fn get_values<'a>(&'a self) -> Box<ListAccessor + 'a>;
}

struct MapList<'a> {
  elements: Vec<&'a Field>,
}

/// Macro to generate type-safe get_xxx methods for primitive types,
/// e.g. get_bool, get_short
macro_rules! map_list_primitive_accessor {
  ($METHOD:ident, $VARIANT:ident, $TY:ty) => {
    fn $METHOD(&self, i: usize) -> Result<$TY> {
      match self.elements[i] {
        Field::$VARIANT(v) => Ok(*v),
        _ => Err(general_err!(
          "Cannot access {} as {}",
          self.elements[i].get_type_name(), stringify!($VARIANT))
        )
      }
    }
  }
}

impl<'a> ListAccessor for MapList<'a> {
  map_list_primitive_accessor!(get_bool, Bool, bool);

  map_list_primitive_accessor!(get_byte, Byte, i8);

  map_list_primitive_accessor!(get_short, Short, i16);

  map_list_primitive_accessor!(get_int, Int, i32);

  map_list_primitive_accessor!(get_long, Long, i64);

  map_list_primitive_accessor!(get_ubyte, UByte, u8);

  map_list_primitive_accessor!(get_ushort, UShort, u16);

  map_list_primitive_accessor!(get_uint, UInt, u32);

  map_list_primitive_accessor!(get_ulong, ULong, u64);

  map_list_primitive_accessor!(get_float, Float, f32);

  map_list_primitive_accessor!(get_double, Double, f64);

  map_list_primitive_accessor!(get_timestamp, Timestamp, u64);

  list_complex_accessor!(get_decimal, Decimal, Decimal);

  list_complex_accessor!(get_string, Str, String);

  list_complex_accessor!(get_bytes, Bytes, ByteArray);

  list_complex_accessor!(get_group, Group, Row);

  list_complex_accessor!(get_list, ListInternal, List);

  list_complex_accessor!(get_map, MapInternal, Map);
}

impl MapAccessor for Map {
  fn get_keys<'a>(&'a self) -> Box<ListAccessor + 'a> {
    let map_list = MapList {
      elements: self.entries.iter().map(|v| &v.0).collect(),
    };
    Box::new(map_list)
  }

  fn get_values<'a>(&'a self) -> Box<ListAccessor + 'a> {
    let map_list = MapList {
      elements: self.entries.iter().map(|v| &v.1).collect(),
    };
    Box::new(map_list)
  }
}

/// API to represent a single field in a `Row`.
#[derive(Clone, Debug, PartialEq)]
pub enum Field {
  // Primitive types
  /// Null value.
  Null,
  /// Boolean value (`true`, `false`).
  Bool(bool),
  /// Signed integer INT_8.
  Byte(i8),
  /// Signed integer INT_16.
  Short(i16),
  /// Signed integer INT_32.
  Int(i32),
  /// Signed integer INT_64.
  Long(i64),
  // Unsigned integer UINT_8.
  UByte(u8),
  // Unsigned integer UINT_16.
  UShort(u16),
  // Unsigned integer UINT_32.
  UInt(u32),
  // Unsigned integer UINT_64.
  ULong(u64),
  /// IEEE 32-bit floating point value.
  Float(f32),
  /// IEEE 64-bit floating point value.
  Double(f64),
  /// Decimal value.
  Decimal(Decimal),
  /// UTF-8 encoded character string.
  Str(String),
  /// General binary value.
  Bytes(ByteArray),
  /// Date without a time of day, stores the number of days from the
  /// Unix epoch, 1 January 1970.
  Date(u32),
  /// Milliseconds from the Unix epoch, 1 January 1970.
  Timestamp(u64),

  // ----------------------------------------------------------------------
  // Complex types
  /// Struct, child elements are tuples of field-value pairs.
  Group(Row),
  /// List of elements.
  ListInternal(List),
  /// List of key-value pairs.
  MapInternal(Map),
}

impl Field {
  /// Get the type name.
  fn get_type_name(&self) -> &'static str {
    match *self {
      Field::Null => "Null",
      Field::Bool(_) => "Bool",
      Field::Byte(_) => "Byte",
      Field::Short(_) => "Short",
      Field::Int(_) => "Int",
      Field::Long(_) => "Long",
      Field::UByte(_) => "UByte",
      Field::UShort(_) => "UShort",
      Field::UInt(_) => "UInt",
      Field::ULong(_) => "ULong",
      Field::Float(_) => "Float",
      Field::Double(_) => "Double",
      Field::Decimal(_) => "Decimal",
      Field::Date(_) => "Date",
      Field::Str(_) => "Str",
      Field::Bytes(_) => "Bytes",
      Field::Timestamp(_) => "Timestamp",
      Field::Group(_) => "Group",
      Field::ListInternal(_) => "ListInternal",
      Field::MapInternal(_) => "MapInternal",
    }
  }

  /// Determines if this Row represents a primitive value.
  pub fn is_primitive(&self) -> bool {
    match *self {
      Field::Group(_) => false,
      Field::ListInternal(_) => false,
      Field::MapInternal(_) => false,
      _ => true,
    }
  }

  /// Converts Parquet BOOLEAN type with logical type into `bool` value.
  #[inline]
  pub fn convert_bool(_descr: &ColumnDescPtr, value: bool) -> Self { Field::Bool(value) }

  /// Converts Parquet INT32 type with logical type into `i32` value.
  #[inline]
  pub fn convert_int32(descr: &ColumnDescPtr, value: i32) -> Self {
    match descr.logical_type() {
      LogicalType::INT_8 => Field::Byte(value as i8),
      LogicalType::INT_16 => Field::Short(value as i16),
      LogicalType::INT_32 | LogicalType::NONE => Field::Int(value),
      LogicalType::UINT_8 => Field::UByte(value as u8),
      LogicalType::UINT_16 => Field::UShort(value as u16),
      LogicalType::UINT_32 => Field::UInt(value as u32),
      LogicalType::DATE => Field::Date(value as u32),
      LogicalType::DECIMAL => Field::Decimal(Decimal::from_i32(
        value,
        descr.type_precision(),
        descr.type_scale(),
      )),
      _ => nyi!(descr, value),
    }
  }

  /// Converts Parquet INT64 type with logical type into `i64` value.
  #[inline]
  pub fn convert_int64(descr: &ColumnDescPtr, value: i64) -> Self {
    match descr.logical_type() {
      LogicalType::INT_64 | LogicalType::NONE => Field::Long(value),
      LogicalType::UINT_64 => Field::ULong(value as u64),
      LogicalType::TIMESTAMP_MILLIS => Field::Timestamp(value as u64),
      LogicalType::DECIMAL => Field::Decimal(Decimal::from_i64(
        value,
        descr.type_precision(),
        descr.type_scale(),
      )),
      _ => nyi!(descr, value),
    }
  }

  /// Converts Parquet INT96 (nanosecond timestamps) type and logical type into
  /// `Timestamp` value.
  #[inline]
  pub fn convert_int96(_descr: &ColumnDescPtr, value: Int96) -> Self {
    const JULIAN_DAY_OF_EPOCH: i64 = 2_440_588;
    const SECONDS_PER_DAY: i64 = 86_400;
    const MILLIS_PER_SECOND: i64 = 1_000;

    let day = value.data()[2] as i64;
    let nanoseconds = ((value.data()[1] as i64) << 32) + value.data()[0] as i64;
    let seconds = (day - JULIAN_DAY_OF_EPOCH) * SECONDS_PER_DAY;
    let millis = seconds * MILLIS_PER_SECOND + nanoseconds / 1_000_000;

    // TODO: Add support for negative milliseconds.
    // Chrono library does not handle negative timestamps, but we could probably write
    // something similar to java.util.Date and java.util.Calendar.
    if millis < 0 {
      panic!(
        "Expected non-negative milliseconds when converting Int96, found {}",
        millis
      );
    }

    Field::Timestamp(millis as u64)
  }

  /// Converts Parquet FLOAT type with logical type into `f32` value.
  #[inline]
  pub fn convert_float(_descr: &ColumnDescPtr, value: f32) -> Self { Field::Float(value) }

  /// Converts Parquet DOUBLE type with logical type into `f64` value.
  #[inline]
  pub fn convert_double(_descr: &ColumnDescPtr, value: f64) -> Self {
    Field::Double(value)
  }

  /// Converts Parquet BYTE_ARRAY type with logical type into either UTF8 string or
  /// array of bytes.
  #[inline]
  pub fn convert_byte_array(descr: &ColumnDescPtr, value: ByteArray) -> Self {
    match descr.physical_type() {
      PhysicalType::BYTE_ARRAY => match descr.logical_type() {
        LogicalType::UTF8 | LogicalType::ENUM | LogicalType::JSON => {
          let value = unsafe { String::from_utf8_unchecked(value.data().to_vec()) };
          Field::Str(value)
        },
        LogicalType::BSON | LogicalType::NONE => Field::Bytes(value),
        LogicalType::DECIMAL => Field::Decimal(Decimal::from_bytes(
          value,
          descr.type_precision(),
          descr.type_scale(),
        )),
        _ => nyi!(descr, value),
      },
      PhysicalType::FIXED_LEN_BYTE_ARRAY => match descr.logical_type() {
        LogicalType::DECIMAL => Field::Decimal(Decimal::from_bytes(
          value,
          descr.type_precision(),
          descr.type_scale(),
        )),
        LogicalType::NONE => Field::Bytes(value),
        _ => nyi!(descr, value),
      },
      _ => nyi!(descr, value),
    }
  }
}

impl fmt::Display for Field {
  fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
    match *self {
      Field::Null => write!(f, "null"),
      Field::Bool(value) => write!(f, "{}", value),
      Field::Byte(value) => write!(f, "{}", value),
      Field::Short(value) => write!(f, "{}", value),
      Field::Int(value) => write!(f, "{}", value),
      Field::Long(value) => write!(f, "{}", value),
      Field::UByte(value) => write!(f, "{}", value),
      Field::UShort(value) => write!(f, "{}", value),
      Field::UInt(value) => write!(f, "{}", value),
      Field::ULong(value) => write!(f, "{}", value),
      Field::Float(value) => {
        if value > 1e19 || value < 1e-15 {
          write!(f, "{:E}", value)
        } else {
          write!(f, "{:?}", value)
        }
      },
      Field::Double(value) => {
        if value > 1e19 || value < 1e-15 {
          write!(f, "{:E}", value)
        } else {
          write!(f, "{:?}", value)
        }
      },
      Field::Decimal(ref value) => write!(f, "{}", convert_decimal_to_string(value)),
      Field::Str(ref value) => write!(f, "\"{}\"", value),
      Field::Bytes(ref value) => write!(f, "{:?}", value.data()),
      Field::Date(value) => write!(f, "{}", convert_date_to_string(value)),
      Field::Timestamp(value) => write!(f, "{}", convert_timestamp_to_string(value)),
      Field::Group(ref fields) => write!(f, "{}", fields),
      Field::ListInternal(ref list) => {
        let elems = &list.elements;
        write!(f, "[")?;
        for (i, field) in elems.iter().enumerate() {
          field.fmt(f)?;
          if i < elems.len() - 1 {
            write!(f, ", ")?;
          }
        }
        write!(f, "]")
      },
      Field::MapInternal(ref map) => {
        let entries = &map.entries;
        write!(f, "{{")?;
        for (i, &(ref key, ref value)) in entries.iter().enumerate() {
          key.fmt(f)?;
          write!(f, " -> ")?;
          value.fmt(f)?;
          if i < entries.len() - 1 {
            write!(f, ", ")?;
          }
        }
        write!(f, "}}")
      },
    }
  }
}

/// Helper method to convert Parquet date into a string.
/// Input `value` is a number of days since the epoch in UTC.
/// Date is displayed in local timezone.
#[inline]
fn convert_date_to_string(value: u32) -> String {
  static NUM_SECONDS_IN_DAY: i64 = 60 * 60 * 24;
  let dt = Local.timestamp(value as i64 * NUM_SECONDS_IN_DAY, 0).date();
  format!("{}", dt.format("%Y-%m-%d %:z"))
}

/// Helper method to convert Parquet timestamp into a string.
/// Input `value` is a number of milliseconds since the epoch in UTC.
/// Datetime is displayed in local timezone.
#[inline]
fn convert_timestamp_to_string(value: u64) -> String {
  let dt = Local.timestamp((value / 1000) as i64, 0);
  format!("{}", dt.format("%Y-%m-%d %H:%M:%S %:z"))
}

/// Helper method to convert Parquet decimal into a string.
/// We assert that `scale >= 0` and `precision > scale`, but this will be enforced
/// when constructing Parquet schema.
#[inline]
fn convert_decimal_to_string(decimal: &Decimal) -> String {
  assert!(decimal.scale() >= 0 && decimal.precision() > decimal.scale());

  // Specify as signed bytes to resolve sign as part of conversion.
  let num = BigInt::from_signed_bytes_be(decimal.data());

  // Offset of the first digit in a string.
  let negative = if num.sign() == Sign::Minus { 1 } else { 0 };
  let mut num_str = num.to_string();
  let mut point = num_str.len() as i32 - decimal.scale() - negative;

  // Convert to string form without scientific notation.
  if point <= 0 {
    // Zeros need to be prepended to the unscaled value.
    while point < 0 {
      num_str.insert(negative as usize, '0');
      point += 1;
    }
    num_str.insert_str(negative as usize, "0.");
  } else {
    // No zeroes need to be prepended to the unscaled value, simply insert decimal point.
    num_str.insert((point + negative) as usize, '.');
  }

  num_str
}

#[cfg(test)]
mod tests {
  use std::rc::Rc;

  use super::*;
  use chrono;
  use schema::types::{ColumnDescriptor, ColumnPath, PrimitiveTypeBuilder};

  /// Creates test column descriptor based on provided type parameters.
  macro_rules! make_column_descr {
    ($physical_type:expr, $logical_type:expr) => {{
      let tpe = PrimitiveTypeBuilder::new("col", $physical_type)
        .with_logical_type($logical_type)
        .build()
        .unwrap();
      Rc::new(ColumnDescriptor::new(
        Rc::new(tpe),
        None,
        0,
        0,
        ColumnPath::from("col"),
      ))
    }};
    ($physical_type:expr, $logical_type:expr, $len:expr, $prec:expr, $scale:expr) => {{
      let tpe = PrimitiveTypeBuilder::new("col", $physical_type)
        .with_logical_type($logical_type)
        .with_length($len)
        .with_precision($prec)
        .with_scale($scale)
        .build()
        .unwrap();
      Rc::new(ColumnDescriptor::new(
        Rc::new(tpe),
        None,
        0,
        0,
        ColumnPath::from("col"),
      ))
    }};
  }

  #[test]
  fn test_row_convert_bool() {
    // BOOLEAN value does not depend on logical type
    let descr = make_column_descr![PhysicalType::BOOLEAN, LogicalType::NONE];

    let row = Field::convert_bool(&descr, true);
    assert_eq!(row, Field::Bool(true));

    let row = Field::convert_bool(&descr, false);
    assert_eq!(row, Field::Bool(false));
  }

  #[test]
  fn test_row_convert_int32() {
    let descr = make_column_descr![PhysicalType::INT32, LogicalType::INT_8];
    let row = Field::convert_int32(&descr, 111);
    assert_eq!(row, Field::Byte(111));

    let descr = make_column_descr![PhysicalType::INT32, LogicalType::INT_16];
    let row = Field::convert_int32(&descr, 222);
    assert_eq!(row, Field::Short(222));

    let descr = make_column_descr![PhysicalType::INT32, LogicalType::INT_32];
    let row = Field::convert_int32(&descr, 333);
    assert_eq!(row, Field::Int(333));

    let descr = make_column_descr![PhysicalType::INT32, LogicalType::UINT_8];
    let row = Field::convert_int32(&descr, -1);
    assert_eq!(row, Field::UByte(255));

    let descr = make_column_descr![PhysicalType::INT32, LogicalType::UINT_16];
    let row = Field::convert_int32(&descr, 256);
    assert_eq!(row, Field::UShort(256));

    let descr = make_column_descr![PhysicalType::INT32, LogicalType::UINT_32];
    let row = Field::convert_int32(&descr, 1234);
    assert_eq!(row, Field::UInt(1234));

    let descr = make_column_descr![PhysicalType::INT32, LogicalType::NONE];
    let row = Field::convert_int32(&descr, 444);
    assert_eq!(row, Field::Int(444));

    let descr = make_column_descr![PhysicalType::INT32, LogicalType::DATE];
    let row = Field::convert_int32(&descr, 14611);
    assert_eq!(row, Field::Date(14611));

    let descr = make_column_descr![PhysicalType::INT32, LogicalType::DECIMAL, 0, 8, 2];
    let row = Field::convert_int32(&descr, 444);
    assert_eq!(row, Field::Decimal(Decimal::from_i32(444, 8, 2)));
  }

  #[test]
  fn test_row_convert_int64() {
    let descr = make_column_descr![PhysicalType::INT64, LogicalType::INT_64];
    let row = Field::convert_int64(&descr, 1111);
    assert_eq!(row, Field::Long(1111));

    let descr = make_column_descr![PhysicalType::INT64, LogicalType::UINT_64];
    let row = Field::convert_int64(&descr, 78239823);
    assert_eq!(row, Field::ULong(78239823));

    let descr = make_column_descr![PhysicalType::INT64, LogicalType::TIMESTAMP_MILLIS];
    let row = Field::convert_int64(&descr, 1541186529153);
    assert_eq!(row, Field::Timestamp(1541186529153));

    let descr = make_column_descr![PhysicalType::INT64, LogicalType::NONE];
    let row = Field::convert_int64(&descr, 2222);
    assert_eq!(row, Field::Long(2222));

    let descr = make_column_descr![PhysicalType::INT64, LogicalType::DECIMAL, 0, 8, 2];
    let row = Field::convert_int64(&descr, 3333);
    assert_eq!(row, Field::Decimal(Decimal::from_i64(3333, 8, 2)));
  }

  #[test]
  fn test_row_convert_int96() {
    // INT96 value does not depend on logical type
    let descr = make_column_descr![PhysicalType::INT96, LogicalType::NONE];

    let value = Int96::from(vec![0, 0, 2454923]);
    let row = Field::convert_int96(&descr, value);
    assert_eq!(row, Field::Timestamp(1238544000000));

    let value = Int96::from(vec![4165425152, 13, 2454923]);
    let row = Field::convert_int96(&descr, value);
    assert_eq!(row, Field::Timestamp(1238544060000));
  }

  #[test]
  #[should_panic(expected = "Expected non-negative milliseconds when converting Int96")]
  fn test_row_convert_int96_invalid() {
    // INT96 value does not depend on logical type
    let descr = make_column_descr![PhysicalType::INT96, LogicalType::NONE];

    let value = Int96::from(vec![0, 0, 0]);
    Field::convert_int96(&descr, value);
  }

  #[test]
  fn test_row_convert_float() {
    // FLOAT value does not depend on logical type
    let descr = make_column_descr![PhysicalType::FLOAT, LogicalType::NONE];
    let row = Field::convert_float(&descr, 2.31);
    assert_eq!(row, Field::Float(2.31));
  }

  #[test]
  fn test_row_convert_double() {
    // DOUBLE value does not depend on logical type
    let descr = make_column_descr![PhysicalType::DOUBLE, LogicalType::NONE];
    let row = Field::convert_double(&descr, 1.56);
    assert_eq!(row, Field::Double(1.56));
  }

  #[test]
  fn test_row_convert_byte_array() {
    // UTF8
    let descr = make_column_descr![PhysicalType::BYTE_ARRAY, LogicalType::UTF8];
    let value = ByteArray::from(vec![b'A', b'B', b'C', b'D']);
    let row = Field::convert_byte_array(&descr, value);
    assert_eq!(row, Field::Str("ABCD".to_string()));

    // ENUM
    let descr = make_column_descr![PhysicalType::BYTE_ARRAY, LogicalType::ENUM];
    let value = ByteArray::from(vec![b'1', b'2', b'3']);
    let row = Field::convert_byte_array(&descr, value);
    assert_eq!(row, Field::Str("123".to_string()));

    // JSON
    let descr = make_column_descr![PhysicalType::BYTE_ARRAY, LogicalType::JSON];
    let value = ByteArray::from(vec![b'{', b'"', b'a', b'"', b':', b'1', b'}']);
    let row = Field::convert_byte_array(&descr, value);
    assert_eq!(row, Field::Str("{\"a\":1}".to_string()));

    // NONE
    let descr = make_column_descr![PhysicalType::BYTE_ARRAY, LogicalType::NONE];
    let value = ByteArray::from(vec![1, 2, 3, 4, 5]);
    let row = Field::convert_byte_array(&descr, value.clone());
    assert_eq!(row, Field::Bytes(value));

    // BSON
    let descr = make_column_descr![PhysicalType::BYTE_ARRAY, LogicalType::BSON];
    let value = ByteArray::from(vec![1, 2, 3, 4, 5]);
    let row = Field::convert_byte_array(&descr, value.clone());
    assert_eq!(row, Field::Bytes(value));

    // DECIMAL
    let descr =
      make_column_descr![PhysicalType::BYTE_ARRAY, LogicalType::DECIMAL, 0, 8, 2];
    let value = ByteArray::from(vec![207, 200]);
    let row = Field::convert_byte_array(&descr, value.clone());
    assert_eq!(row, Field::Decimal(Decimal::from_bytes(value, 8, 2)));

    // DECIMAL (FIXED_LEN_BYTE_ARRAY)
    let descr = make_column_descr![
      PhysicalType::FIXED_LEN_BYTE_ARRAY,
      LogicalType::DECIMAL,
      8,
      17,
      5
    ];
    let value = ByteArray::from(vec![0, 0, 0, 0, 0, 4, 147, 224]);
    let row = Field::convert_byte_array(&descr, value.clone());
    assert_eq!(row, Field::Decimal(Decimal::from_bytes(value, 17, 5)));

    // NONE (FIXED_LEN_BYTE_ARRAY)
    let descr = make_column_descr![
      PhysicalType::FIXED_LEN_BYTE_ARRAY,
      LogicalType::NONE,
      6,
      0,
      0
    ];
    let value = ByteArray::from(vec![1, 2, 3, 4, 5, 6]);
    let row = Field::convert_byte_array(&descr, value.clone());
    assert_eq!(row, Field::Bytes(value));
  }

  #[test]
  fn test_convert_date_to_string() {
    fn check_date_conversion(y: u32, m: u32, d: u32) {
      let datetime = chrono::NaiveDate::from_ymd(y as i32, m, d).and_hms(0, 0, 0);
      let dt = Local.from_utc_datetime(&datetime);
      let res = convert_date_to_string((dt.timestamp() / 60 / 60 / 24) as u32);
      let exp = format!("{}", dt.format("%Y-%m-%d %:z"));
      assert_eq!(res, exp);
    }

    check_date_conversion(2010, 01, 02);
    check_date_conversion(2014, 05, 01);
    check_date_conversion(2016, 02, 29);
    check_date_conversion(2017, 09, 12);
    check_date_conversion(2018, 03, 31);
  }

  #[test]
  fn test_convert_timestamp_to_string() {
    fn check_datetime_conversion(y: u32, m: u32, d: u32, h: u32, mi: u32, s: u32) {
      let datetime = chrono::NaiveDate::from_ymd(y as i32, m, d).and_hms(h, mi, s);
      let dt = Local.from_utc_datetime(&datetime);
      let res = convert_timestamp_to_string(dt.timestamp_millis() as u64);
      let exp = format!("{}", dt.format("%Y-%m-%d %H:%M:%S %:z"));
      assert_eq!(res, exp);
    }

    check_datetime_conversion(2010, 01, 02, 13, 12, 54);
    check_datetime_conversion(2011, 01, 03, 08, 23, 01);
    check_datetime_conversion(2012, 04, 05, 11, 06, 32);
    check_datetime_conversion(2013, 05, 12, 16, 38, 00);
    check_datetime_conversion(2014, 11, 28, 21, 15, 12);
  }

  #[test]
  fn test_convert_float_to_string() {
    assert_eq!(format!("{}", Field::Float(1.0)), "1.0");
    assert_eq!(format!("{}", Field::Float(9.63)), "9.63");
    assert_eq!(format!("{}", Field::Float(1e-15)), "0.000000000000001");
    assert_eq!(format!("{}", Field::Float(1e-16)), "1E-16");
    assert_eq!(format!("{}", Field::Float(1e19)), "10000000000000000000.0");
    assert_eq!(format!("{}", Field::Float(1e20)), "1E20");
    assert_eq!(format!("{}", Field::Float(1.7976931E30)), "1.7976931E30");
    assert_eq!(format!("{}", Field::Float(-1.7976931E30)), "-1.7976931E30");
  }

  #[test]
  fn test_convert_double_to_string() {
    assert_eq!(format!("{}", Field::Double(1.0)), "1.0");
    assert_eq!(format!("{}", Field::Double(9.63)), "9.63");
    assert_eq!(format!("{}", Field::Double(1e-15)), "0.000000000000001");
    assert_eq!(format!("{}", Field::Double(1e-16)), "1E-16");
    assert_eq!(format!("{}", Field::Double(1e19)), "10000000000000000000.0");
    assert_eq!(format!("{}", Field::Double(1e20)), "1E20");
    assert_eq!(
      format!("{}", Field::Double(1.79769313486E308)),
      "1.79769313486E308"
    );
    assert_eq!(
      format!("{}", Field::Double(-1.79769313486E308)),
      "-1.79769313486E308"
    );
  }

  #[test]
  fn test_convert_decimal_to_string() {
    // Helper method to compare decimal
    fn check_decimal(bytes: Vec<u8>, precision: i32, scale: i32, res: &str) {
      let decimal = Decimal::from_bytes(ByteArray::from(bytes), precision, scale);
      assert_eq!(convert_decimal_to_string(&decimal), res);
    }

    // This example previously used to fail in some engines
    check_decimal(
      vec![0, 0, 0, 0, 0, 0, 0, 0, 13, 224, 182, 179, 167, 100, 0, 0],
      38,
      18,
      "1.000000000000000000",
    );
    check_decimal(
      vec![
        249, 233, 247, 16, 185, 192, 202, 223, 215, 165, 192, 166, 67, 72,
      ],
      36,
      28,
      "-12344.0242342304923409234234293432",
    );
    check_decimal(vec![0, 0, 0, 0, 0, 4, 147, 224], 17, 5, "3.00000");
    check_decimal(vec![0, 0, 0, 0, 1, 201, 195, 140], 18, 2, "300000.12");
    check_decimal(vec![207, 200], 10, 2, "-123.44");
    check_decimal(vec![207, 200], 10, 8, "-0.00012344");
  }

  #[test]
  fn test_row_display() {
    // Primitive types
    assert_eq!(format!("{}", Field::Null), "null");
    assert_eq!(format!("{}", Field::Bool(true)), "true");
    assert_eq!(format!("{}", Field::Bool(false)), "false");
    assert_eq!(format!("{}", Field::Byte(1)), "1");
    assert_eq!(format!("{}", Field::Short(2)), "2");
    assert_eq!(format!("{}", Field::Int(3)), "3");
    assert_eq!(format!("{}", Field::Long(4)), "4");
    assert_eq!(format!("{}", Field::UByte(1)), "1");
    assert_eq!(format!("{}", Field::UShort(2)), "2");
    assert_eq!(format!("{}", Field::UInt(3)), "3");
    assert_eq!(format!("{}", Field::ULong(4)), "4");
    assert_eq!(format!("{}", Field::Float(5.0)), "5.0");
    assert_eq!(format!("{}", Field::Float(5.1234)), "5.1234");
    assert_eq!(format!("{}", Field::Double(6.0)), "6.0");
    assert_eq!(format!("{}", Field::Double(6.1234)), "6.1234");
    assert_eq!(format!("{}", Field::Str("abc".to_string())), "\"abc\"");
    assert_eq!(
      format!("{}", Field::Bytes(ByteArray::from(vec![1, 2, 3]))),
      "[1, 2, 3]"
    );
    assert_eq!(
      format!("{}", Field::Date(14611)),
      convert_date_to_string(14611)
    );
    assert_eq!(
      format!("{}", Field::Timestamp(1262391174000)),
      convert_timestamp_to_string(1262391174000)
    );
    assert_eq!(
      format!("{}", Field::Decimal(Decimal::from_i32(4, 8, 2))),
      convert_decimal_to_string(&Decimal::from_i32(4, 8, 2))
    );

    // Complex types
    let fields = vec![
      ("x".to_string(), Field::Null),
      ("Y".to_string(), Field::Int(2)),
      ("z".to_string(), Field::Float(3.1)),
      ("a".to_string(), Field::Str("abc".to_string())),
    ];
    let row = Field::Group(make_row(fields));
    assert_eq!(format!("{}", row), "{x: null, Y: 2, z: 3.1, a: \"abc\"}");

    let row = Field::ListInternal(make_list(vec![
      Field::Int(2),
      Field::Int(1),
      Field::Null,
      Field::Int(12),
    ]));
    assert_eq!(format!("{}", row), "[2, 1, null, 12]");

    let row = Field::MapInternal(make_map(vec![
      (Field::Int(1), Field::Float(1.2)),
      (Field::Int(2), Field::Float(4.5)),
      (Field::Int(3), Field::Float(2.3)),
    ]));
    assert_eq!(format!("{}", row), "{1 -> 1.2, 2 -> 4.5, 3 -> 2.3}");
  }

  #[test]
  fn test_is_primitive() {
    // primitives
    assert!(Field::Null.is_primitive());
    assert!(Field::Bool(true).is_primitive());
    assert!(Field::Bool(false).is_primitive());
    assert!(Field::Byte(1).is_primitive());
    assert!(Field::Short(2).is_primitive());
    assert!(Field::Int(3).is_primitive());
    assert!(Field::Long(4).is_primitive());
    assert!(Field::UByte(1).is_primitive());
    assert!(Field::UShort(2).is_primitive());
    assert!(Field::UInt(3).is_primitive());
    assert!(Field::ULong(4).is_primitive());
    assert!(Field::Float(5.0).is_primitive());
    assert!(Field::Float(5.1234).is_primitive());
    assert!(Field::Double(6.0).is_primitive());
    assert!(Field::Double(6.1234).is_primitive());
    assert!(Field::Str("abc".to_string()).is_primitive());
    assert!(Field::Bytes(ByteArray::from(vec![1, 2, 3])).is_primitive());
    assert!(Field::Timestamp(12345678).is_primitive());
    assert!(Field::Decimal(Decimal::from_i32(4, 8, 2)).is_primitive());

    // complex types
    assert_eq!(
      false,
      Field::Group(make_row(vec![
        ("x".to_string(), Field::Null),
        ("Y".to_string(), Field::Int(2)),
        ("z".to_string(), Field::Float(3.1)),
        ("a".to_string(), Field::Str("abc".to_string()))
      ]))
      .is_primitive()
    );

    assert_eq!(
      false,
      Field::ListInternal(make_list(vec![
        Field::Int(2),
        Field::Int(1),
        Field::Null,
        Field::Int(12)
      ]))
      .is_primitive()
    );

    assert_eq!(
      false,
      Field::MapInternal(make_map(vec![
        (Field::Int(1), Field::Float(1.2)),
        (Field::Int(2), Field::Float(4.5)),
        (Field::Int(3), Field::Float(2.3))
      ]))
      .is_primitive()
    );
  }

  #[test]
  fn test_row_primitive_accessors() {
    // primitives
    let row = make_row(vec![
      ("a".to_string(), Field::Null),
      ("b".to_string(), Field::Bool(false)),
      ("c".to_string(), Field::Byte(3)),
      ("d".to_string(), Field::Short(4)),
      ("e".to_string(), Field::Int(5)),
      ("f".to_string(), Field::Long(6)),
      ("g".to_string(), Field::UByte(3)),
      ("h".to_string(), Field::UShort(4)),
      ("i".to_string(), Field::UInt(5)),
      ("j".to_string(), Field::ULong(6)),
      ("k".to_string(), Field::Float(7.1)),
      ("l".to_string(), Field::Double(8.1)),
      ("m".to_string(), Field::Str("abc".to_string())),
      (
        "n".to_string(),
        Field::Bytes(ByteArray::from(vec![1, 2, 3, 4, 5])),
      ),
      ("o".to_string(), Field::Decimal(Decimal::from_i32(4, 7, 2))),
    ]);

    assert_eq!(false, row.get_bool(1).unwrap());
    assert_eq!(3, row.get_byte(2).unwrap());
    assert_eq!(4, row.get_short(3).unwrap());
    assert_eq!(5, row.get_int(4).unwrap());
    assert_eq!(6, row.get_long(5).unwrap());
    assert_eq!(3, row.get_ubyte(6).unwrap());
    assert_eq!(4, row.get_ushort(7).unwrap());
    assert_eq!(5, row.get_uint(8).unwrap());
    assert_eq!(6, row.get_ulong(9).unwrap());
    assert_eq!(7.1, row.get_float(10).unwrap());
    assert_eq!(8.1, row.get_double(11).unwrap());
    assert_eq!("abc", row.get_string(12).unwrap());
    assert_eq!(5, row.get_bytes(13).unwrap().len());
    assert_eq!(7, row.get_decimal(14).unwrap().precision());
  }

  #[test]
  fn test_row_primitive_invalid_accessors() {
    // primitives
    let row = make_row(vec![
      ("a".to_string(), Field::Null),
      ("b".to_string(), Field::Bool(false)),
      ("c".to_string(), Field::Byte(3)),
      ("d".to_string(), Field::Short(4)),
      ("e".to_string(), Field::Int(5)),
      ("f".to_string(), Field::Long(6)),
      ("g".to_string(), Field::UByte(3)),
      ("h".to_string(), Field::UShort(4)),
      ("i".to_string(), Field::UInt(5)),
      ("j".to_string(), Field::ULong(6)),
      ("k".to_string(), Field::Float(7.1)),
      ("l".to_string(), Field::Double(8.1)),
      ("m".to_string(), Field::Str("abc".to_string())),
      (
        "n".to_string(),
        Field::Bytes(ByteArray::from(vec![1, 2, 3, 4, 5])),
      ),
      ("o".to_string(), Field::Decimal(Decimal::from_i32(4, 7, 2))),
    ]);

    for i in 0..row.len() {
      assert!(row.get_group(i).is_err());
    }
  }

  #[test]
  fn test_row_complex_accessors() {
    let row = make_row(vec![
      (
        "a".to_string(),
        Field::Group(make_row(vec![
          ("x".to_string(), Field::Null),
          ("Y".to_string(), Field::Int(2)),
        ])),
      ),
      (
        "b".to_string(),
        Field::ListInternal(make_list(vec![
          Field::Int(2),
          Field::Int(1),
          Field::Null,
          Field::Int(12),
        ])),
      ),
      (
        "c".to_string(),
        Field::MapInternal(make_map(vec![
          (Field::Int(1), Field::Float(1.2)),
          (Field::Int(2), Field::Float(4.5)),
          (Field::Int(3), Field::Float(2.3)),
        ])),
      ),
    ]);

    assert_eq!(2, row.get_group(0).unwrap().len());
    assert_eq!(4, row.get_list(1).unwrap().len());
    assert_eq!(3, row.get_map(2).unwrap().len());
  }

  #[test]
  fn test_row_complex_invalid_accessors() {
    let row = make_row(vec![
      (
        "a".to_string(),
        Field::Group(make_row(vec![
          ("x".to_string(), Field::Null),
          ("Y".to_string(), Field::Int(2)),
        ])),
      ),
      (
        "b".to_string(),
        Field::ListInternal(make_list(vec![
          Field::Int(2),
          Field::Int(1),
          Field::Null,
          Field::Int(12),
        ])),
      ),
      (
        "c".to_string(),
        Field::MapInternal(make_map(vec![
          (Field::Int(1), Field::Float(1.2)),
          (Field::Int(2), Field::Float(4.5)),
          (Field::Int(3), Field::Float(2.3)),
        ])),
      ),
    ]);

    assert_eq!(
      ParquetError::General("Cannot access Group as Float".to_string()),
      row.get_float(0).unwrap_err()
    );
    assert_eq!(
      ParquetError::General("Cannot access ListInternal as Float".to_string()),
      row.get_float(1).unwrap_err()
    );
    assert_eq!(
      ParquetError::General("Cannot access MapInternal as Float".to_string()),
      row.get_float(2).unwrap_err()
    );
  }

  #[test]
  fn test_list_primitive_accessors() {
    // primitives
    let list = make_list(vec![Field::Bool(false)]);
    assert_eq!(false, list.get_bool(0).unwrap());

    let list = make_list(vec![Field::Byte(3), Field::Byte(4)]);
    assert_eq!(4, list.get_byte(1).unwrap());

    let list = make_list(vec![Field::Short(4), Field::Short(5), Field::Short(6)]);
    assert_eq!(6, list.get_short(2).unwrap());

    let list = make_list(vec![Field::Int(5)]);
    assert_eq!(5, list.get_int(0).unwrap());

    let list = make_list(vec![Field::Long(6), Field::Long(7)]);
    assert_eq!(7, list.get_long(1).unwrap());

    let list = make_list(vec![Field::UByte(3), Field::UByte(4)]);
    assert_eq!(4, list.get_ubyte(1).unwrap());

    let list = make_list(vec![Field::UShort(4), Field::UShort(5), Field::UShort(6)]);
    assert_eq!(6, list.get_ushort(2).unwrap());

    let list = make_list(vec![Field::UInt(5)]);
    assert_eq!(5, list.get_uint(0).unwrap());

    let list = make_list(vec![Field::ULong(6), Field::ULong(7)]);
    assert_eq!(7, list.get_ulong(1).unwrap());

    let list = make_list(vec![
      Field::Float(8.1),
      Field::Float(9.2),
      Field::Float(10.3),
    ]);
    assert_eq!(10.3, list.get_float(2).unwrap());

    let list = make_list(vec![Field::Double(3.1415)]);
    assert_eq!(3.1415, list.get_double(0).unwrap());

    let list = make_list(vec![Field::Str("abc".to_string())]);
    assert_eq!(&"abc".to_string(), list.get_string(0).unwrap());

    let list = make_list(vec![Field::Bytes(ByteArray::from(vec![1, 2, 3, 4, 5]))]);
    assert_eq!(&[1, 2, 3, 4, 5], list.get_bytes(0).unwrap().data());

    let list = make_list(vec![Field::Decimal(Decimal::from_i32(4, 5, 2))]);
    assert_eq!(&[0, 0, 0, 4], list.get_decimal(0).unwrap().data());
  }

  #[test]
  fn test_list_primitive_invalid_accessors() {
    // primitives
    let list = make_list(vec![Field::Bool(false)]);
    assert!(list.get_byte(0).is_err());

    let list = make_list(vec![Field::Byte(3), Field::Byte(4)]);
    assert!(list.get_short(1).is_err());

    let list = make_list(vec![Field::Short(4), Field::Short(5), Field::Short(6)]);
    assert!(list.get_int(2).is_err());

    let list = make_list(vec![Field::Int(5)]);
    assert!(list.get_long(0).is_err());

    let list = make_list(vec![Field::Long(6), Field::Long(7)]);
    assert!(list.get_float(1).is_err());

    let list = make_list(vec![Field::UByte(3), Field::UByte(4)]);
    assert!(list.get_short(1).is_err());

    let list = make_list(vec![Field::UShort(4), Field::UShort(5), Field::UShort(6)]);
    assert!(list.get_int(2).is_err());

    let list = make_list(vec![Field::UInt(5)]);
    assert!(list.get_long(0).is_err());

    let list = make_list(vec![Field::ULong(6), Field::ULong(7)]);
    assert!(list.get_float(1).is_err());

    let list = make_list(vec![
      Field::Float(8.1),
      Field::Float(9.2),
      Field::Float(10.3),
    ]);
    assert!(list.get_double(2).is_err());

    let list = make_list(vec![Field::Double(3.1415)]);
    assert!(list.get_string(0).is_err());

    let list = make_list(vec![Field::Str("abc".to_string())]);
    assert!(list.get_bytes(0).is_err());

    let list = make_list(vec![Field::Bytes(ByteArray::from(vec![1, 2, 3, 4, 5]))]);
    assert!(list.get_bool(0).is_err());

    let list = make_list(vec![Field::Decimal(Decimal::from_i32(4, 5, 2))]);
    assert!(list.get_bool(0).is_err());
  }

  #[test]
  fn test_list_complex_accessors() {
    let list = make_list(vec![Field::Group(make_row(vec![
      ("x".to_string(), Field::Null),
      ("Y".to_string(), Field::Int(2)),
    ]))]);
    assert_eq!(2, list.get_group(0).unwrap().len());

    let list = make_list(vec![Field::ListInternal(make_list(vec![
      Field::Int(2),
      Field::Int(1),
      Field::Null,
      Field::Int(12),
    ]))]);
    assert_eq!(4, list.get_list(0).unwrap().len());

    let list = make_list(vec![Field::MapInternal(make_map(vec![
      (Field::Int(1), Field::Float(1.2)),
      (Field::Int(2), Field::Float(4.5)),
      (Field::Int(3), Field::Float(2.3)),
    ]))]);
    assert_eq!(3, list.get_map(0).unwrap().len());
  }

  #[test]
  fn test_list_complex_invalid_accessors() {
    let list = make_list(vec![Field::Group(make_row(vec![
      ("x".to_string(), Field::Null),
      ("Y".to_string(), Field::Int(2)),
    ]))]);
    assert_eq!(
      general_err!("Cannot access Group as Float".to_string()),
      list.get_float(0).unwrap_err()
    );

    let list = make_list(vec![Field::ListInternal(make_list(vec![
      Field::Int(2),
      Field::Int(1),
      Field::Null,
      Field::Int(12),
    ]))]);
    assert_eq!(
      general_err!("Cannot access ListInternal as Float".to_string()),
      list.get_float(0).unwrap_err()
    );

    let list = make_list(vec![Field::MapInternal(make_map(vec![
      (Field::Int(1), Field::Float(1.2)),
      (Field::Int(2), Field::Float(4.5)),
      (Field::Int(3), Field::Float(2.3)),
    ]))]);
    assert_eq!(
      general_err!("Cannot access MapInternal as Float".to_string()),
      list.get_float(0).unwrap_err()
    );
  }

  #[test]
  fn test_map_accessors() {
    // a map from int to string
    let map = make_map(vec![
      (Field::Int(1), Field::Str("a".to_string())),
      (Field::Int(2), Field::Str("b".to_string())),
      (Field::Int(3), Field::Str("c".to_string())),
      (Field::Int(4), Field::Str("d".to_string())),
      (Field::Int(5), Field::Str("e".to_string())),
    ]);

    assert_eq!(5, map.len());
    for i in 0..5 {
      assert_eq!((i + 1) as i32, map.get_keys().get_int(i).unwrap());
      assert_eq!(
        &((i as u8 + 'a' as u8) as char).to_string(),
        map.get_values().get_string(i).unwrap()
      );
    }
  }
}