Failing test for reading DataSource$schema

r/R/dataset.R

@@ -98,12 +98,8 @@ Dataset <- R6Class("Dataset", inherit = Object,
     schema = function() shared_ptr(Schema, dataset___Dataset__schema(self))
   )
 )
-Dataset$create <- function(sources, schema = NULL) {
+Dataset$create <- function(sources, schema) {
   assert_is_list_of(sources, "DataSource")
-  if (is.null(schema)) {
-    # TODO: this should somehow align the schema of multiple sources
-    schema <- sources[[1]]$schema
-  }
   assert_is(schema, "Schema")
   shared_ptr(Dataset, dataset___Dataset__create(sources, schema))
 }
@@ -153,7 +149,10 @@ DataSource <- R6Class("DataSource", inherit = Object,
   active = list(
     #' @description
     #' Return the DataSource's `Schema`
-    schema = function() shared_ptr(Schema, dataset___Dataset__schema(self))
+    schema = function() {
+      print("hello")
+      shared_ptr(Schema, dataset___DataSource__schema(self))
+    }
   )
 )
 

r/src/dataset.cpp

@@ -16,6 +16,7 @@
 // under the License.
 
 #include "./arrow_types.h"
+#include <iostream>
 
 #if defined(ARROW_R_WITH_ARROW)
 
@@ -83,6 +84,7 @@ std::shared_ptr<ds::DataSource> dataset___DSDiscovery__Finish2(
 // [[arrow::export]]
 std::shared_ptr<arrow::Schema> dataset___DataSource__schema(
     const std::shared_ptr<ds::DataSource>& source) {
+  std::cout<<source->schema()->ToString()<<std::endl;
   return source->schema();
 }
 

r/tests/testthat/test-dataset.R

@@ -270,6 +270,9 @@ test_that("Assembling a Dataset manually and getting a Table", {
 
   datasource <- dsd$Finish(schm)
   expect_is(datasource, "DataSource")
+  expect_is(datasource$schema, "Schema")
+  print(str(datasource$schema))
+  expect_equal(names(schm), names(datasource$schema))
 
   ds <- Dataset$create(list(datasource), schm)
   expect_is(ds, "Dataset")