ARROW-3815 [R]: refine record batch factory

.travis.yml

@@ -362,6 +362,7 @@ matrix:
     - $TRAVIS_BUILD_DIR/ci/travis_before_script_cpp.sh --only-library
     - export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:$TRAVIS_BUILD_DIR/cpp-install/lib
     - export PKG_CONFIG_PATH=$PKG_CONFIG_PATH:$TRAVIS_BUILD_DIR/cpp-install/lib/pkgconfig
+    - export CXX11FLAGS=-Wall
     - pushd ${TRAVIS_BUILD_DIR}/r
     after_success:
     - Rscript ../ci/travis_upload_r_coverage.R

r/src/array_from_vector.cpp

@@ -763,6 +763,13 @@ std::shared_ptr<arrow::DataType> GetFactorType(SEXP factor) {
 
 std::shared_ptr<arrow::DataType> InferType(SEXP x) {
   switch (TYPEOF(x)) {
+    case ENVSXP:
+      if (Rf_inherits(x, "arrow::Array")) {
+        Rcpp::ConstReferenceSmartPtrInputParameter<std::shared_ptr<arrow::Array>> array(
+            x);
+        return static_cast<std::shared_ptr<arrow::Array>>(array)->type();
+      }
+      break;
     case LGLSXP:
       return boolean();
     case INTSXP:
@@ -915,6 +922,11 @@ bool CheckCompatibleFactor(SEXP obj, const std::shared_ptr<arrow::DataType>& typ
 
 std::shared_ptr<arrow::Array> Array__from_vector(
     SEXP x, const std::shared_ptr<arrow::DataType>& type, bool type_infered) {
+  // short circuit if `x` is already an Array
+  if (Rf_inherits(x, "arrow::Array")) {
+    return Rcpp::ConstReferenceSmartPtrInputParameter<std::shared_ptr<arrow::Array>>(x);
+  }
+
   // special case when we can just use the data from the R vector
   // directly. This still needs to handle the null bitmap
   if (arrow::r::can_reuse_memory(x, type)) {

r/tests/testthat/test-Array.R

@@ -410,3 +410,8 @@ test_that("Array<int8>$as_vector() converts to integer (ARROW-3794)", {
   expect_equal(a$type, uint8())
   expect_equal(a$as_vector(), 0:255)
 })
+
+test_that("array() recognise arrow::Array (ARROW-3815)", {
+  a <- array(1:10)
+  expect_equal(a, array(a))
+})

r/tests/testthat/test-RecordBatch.R

@@ -145,3 +145,8 @@ test_that("RecordBatch dim() and nrow() (ARROW-3816)", {
   expect_equal(dim(batch), c(10L, 2L))
   expect_equal(nrow(batch), 10L)
 })
+
+test_that("record_batch() handles arrow::Array", {
+  batch <- record_batch(x = 1:10, y = arrow::array(1:10))
+  expect_equal(batch$schema, schema(x = int32(), y = int32()))
+})

r/tests/testthat/test-chunkedarray.R

@@ -265,3 +265,10 @@ test_that("chunked_array() handles 0 chunks if given a type", {
     expect_equal(a$length(), 0L)
   }
 })
+
+test_that("chunked_array() can ingest arrays (ARROW-3815)", {
+  expect_equal(
+    chunked_array(1:5, array(6:10))$as_vector(),
+    1:10
+  )
+})