tests/testthat/test-message-reader.R

In arrow: Integration to 'Apache' 'Arrow'

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#
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test_that("MessageReader can be created from raw vectors", {
  batch <- record_batch(x = 1:10)
  bytes <- batch$serialize()

  reader <- MessageReader$create(bytes)

  message <- reader$ReadNextMessage()
  expect_r6_class(message, "Message")
  expect_equal(message$type, MessageType$RECORD_BATCH)
  expect_r6_class(message$body, "Buffer")
  expect_r6_class(message$metadata, "Buffer")

  message <- reader$ReadNextMessage()
  expect_null(message)

  schema <- schema(x = int32())
  bytes <- schema$serialize()

  reader <- MessageReader$create(bytes)

  message <- reader$ReadNextMessage()
  expect_r6_class(message, "Message")
  expect_equal(message$type, MessageType$SCHEMA)
  expect_r6_class(message$body, "Buffer")
  expect_r6_class(message$metadata, "Buffer")

  message <- reader$ReadNextMessage()
  expect_null(message)
})

test_that("MessageReader can be created from input stream", {
  batch <- record_batch(x = 1:10)
  bytes <- batch$serialize()

  stream <- BufferReader$create(bytes)
  expect_r6_class(stream, "BufferReader")

  reader <- MessageReader$create(stream)
  expect_r6_class(reader, "MessageReader")

  message <- reader$ReadNextMessage()
  expect_r6_class(message, "Message")
  expect_equal(message$type, MessageType$RECORD_BATCH)
  expect_r6_class(message$body, "Buffer")
  expect_r6_class(message$metadata, "Buffer")

  message <- reader$ReadNextMessage()
  expect_null(message)

  schema <- schema(x = int32())
  bytes <- schema$serialize()

  stream <- BufferReader$create(bytes)
  expect_r6_class(stream, "BufferReader")

  reader <- MessageReader$create(stream)
  expect_r6_class(reader, "MessageReader")

  message <- reader$ReadNextMessage()
  expect_r6_class(message, "Message")
  expect_equal(message$type, MessageType$SCHEMA)
  expect_r6_class(message$body, "Buffer")
  expect_r6_class(message$metadata, "Buffer")

  message <- reader$ReadNextMessage()
  expect_null(message)
})