[r] Support SparseNDArray writes case (#2755)

* [r] Support sparse nd array writes via libtiledbsoma

* Additional test tweak

* Another test tweak with as-needed datatype recovery

* Micro-cleanup of test file

There was another change here that we were able to revert so also reverting
this one remaining changed line

apis/r/R/SOMASparseNDArray.R

@@ -177,9 +177,6 @@ SOMASparseNDArray <- R6::R6Class(
       self$set_metadata(bbox_flat)
       private$.write_coo_dataframe(coo)
 
-      # tiledb-r always closes the array after a write operation so we need to
-      # manually reopen it until close-on-write is optional
-      self$open("WRITE", internal_use_only = "allowed_use")
       invisible(self)
     },
 
@@ -227,14 +224,26 @@ SOMASparseNDArray <- R6::R6Class(
       if (!is.null(private$tiledb_timestamp)) {
           arr@timestamp <- private$tiledb_timestamp
       }
-      ## spdl::debug("[SOMASparseNDArray] '.write_coo_dataframe' layout '{}' is_sparse '{}' ",
-      ##             tiledb::query_layout(arr), private$.is_sparse)
-      ## if (!private$.is_sparse && tiledb::query_layout(arr) == "UNORDERED") {
-      ##     tiledb::query_layout(arr) <- "GLOBAL_ORDER"
-      ##     cat("*********", tiledb::query_layout(arr), "*****\n")
-      ##     print(arr)
-      ## }
-      arr[] <- values
+      nms <- colnames(values)
+
+      ## the 'soma_data' data type may not have been cached, and if so we need to fetch it
+      if (is.null(private$.type)) {
+          ## TODO: replace with a libtiledbsoma accessor as discussed
+          tpstr <- tiledb::datatype(tiledb::attrs(tiledb::schema(self$uri))[["soma_data"]])
+          arstr <- arrow_type_from_tiledb_type(tpstr)
+          private$.type <- arstr
+      }
+
+      arrsch <- arrow::schema(arrow::field(nms[1], arrow::int64()),
+                              arrow::field(nms[2], arrow::int64()),
+                              arrow::field(nms[3], private$.type))
+
+      tbl <- arrow::arrow_table(values, schema = arrsch)
+      spdl::debug("[SOMASparseNDArray::write] array created, writing to {}", self$uri)
+      naap <- nanoarrow::nanoarrow_allocate_array()
+      nasp <- nanoarrow::nanoarrow_allocate_schema()
+      arrow::as_record_batch(tbl)$export_to_c(naap, nasp)
+      writeArrayFromArrow(self$uri, naap, nasp, "SOMASparseNDArray")
     },
 
     # Internal marking of one or zero based matrices for iterated reads

apis/r/src/arrow.cpp

@@ -152,10 +152,13 @@ void writeArrayFromArrow(const std::string& uri, naxpArray naap, naxpSchema nasp
     } else if (arraytype == "SOMADenseNDArray") {
         arrup = tdbs::SOMADenseNDArray::open(OpenMode::write, uri, somactx,
                                              "unnamed", {}, "auto", ResultOrder::colmajor);
+    } else if (arraytype == "SOMASparseNDArray") {
+        arrup = tdbs::SOMASparseNDArray::open(OpenMode::write, uri, somactx);
+    } else {  // not reached
+        Rcpp::stop(tfm::format("Unexpected array type '%s'", arraytype));
     }
 
     arrup.get()->set_array_data(std::move(schema), std::move(array));
     arrup.get()->write();
     arrup.get()->close();
-
 }