feat(r): Add transmute() implementation

r/sedonadb/R/dataframe.R

@@ -193,6 +193,28 @@ sd_preview <- function(.data, n = NULL, ascii = NULL, width = NULL) {
   invisible(.data)
 }
 
+sd_transmute <- function(.data, ...) {
+  .data <- as_sedonadb_dataframe(.data)
+  expr_quos <- rlang::enquos(...)
+  env <- parent.frame()
+
+  expr_ctx <- sd_expr_ctx(infer_nanoarrow_schema(.data), env)
+  exprs <- lapply(expr_quos, rlang::quo_get_expr)
+  sd_exprs <- lapply(exprs, sd_eval_expr, expr_ctx = expr_ctx, env = env)
+  exprs_names <- names(exprs)
+  if (!is.null(exprs_names)) {
+    for (i in seq_along(sd_exprs)) {
+      name <- exprs_names[i]
+      if (!is.na(name) && name != "") {
+        sd_exprs[[i]] <- sd_expr_alias(sd_exprs[[i]], name, expr_ctx$factory)
+      }
+    }
+  }
+
+  df <- .data$df$transmute(.data$ctx, sd_exprs)
+  new_sedonadb_dataframe(.data$ctx, df)
+}
+
 #' Write DataFrame to (Geo)Parquet files
 #'
 #' Write this DataFrame to one or more (Geo)Parquet files. For input that contains

r/sedonadb/R/expression.R

@@ -158,6 +158,28 @@ sd_eval_expr <- function(expr, expr_ctx = sd_expr_ctx(env = env), env = parent.f
   )
 }
 
+sd_eval <- function(stream, exprs, env = parent.frame()) {
+  stream <- nanoarrow::as_nanoarrow_array_stream(
+    stream,
+    geometry_schema = geoarrow::geoarrow_wkb()
+  )
+  expr_ctx <- sd_expr_ctx(stream$get_schema(), env)
+  sd_exprs <- lapply(exprs, sd_eval_expr, expr_ctx = expr_ctx, env = env)
+  exprs_names <- names(exprs)
+  if (!is.null(exprs_names)) {
+    for (i in seq_along(sd_exprs)) {
+      name <- exprs_names[i]
+      if (!is.na(name) && name != "") {
+        sd_exprs[[i]] <- sd_expr_alias(sd_exprs[[i]], name, expr_ctx$factory)
+      }
+    }
+  }
+
+  stream_out <- nanoarrow::nanoarrow_allocate_array_stream()
+  expr_ctx$factory$evaluate_scalar(sd_exprs, stream, stream_out)
+  stream_out
+}
+
 sd_eval_expr_inner <- function(expr, expr_ctx) {
   if (rlang::is_call(expr)) {
     # Extract `pkg::fun` or `fun` if this is a usual call (e.g., not

r/sedonadb/src/rust/src/dataframe.rs

@@ -33,6 +33,7 @@ use std::{iter::zip, ptr::swap_nonoverlapping, sync::Arc};
 use tokio::runtime::Runtime;
 
 use crate::context::InternalContext;
+use crate::expression::SedonaDBExprFactory;
 use crate::ffi::{import_schema, FFITableProviderR};
 use crate::runtime::wait_for_future_captured_r;
 
@@ -311,4 +312,17 @@ impl InternalDataFrame {
         let inner = self.inner.clone().select(exprs)?;
         Ok(new_data_frame(inner, self.runtime.clone()))
     }
+
+    fn transmute(
+        &self,
+        ctx: &InternalContext,
+        exprs_sexp: savvy::Sexp,
+    ) -> savvy::Result<InternalDataFrame> {
+        let exprs = SedonaDBExprFactory::exprs(exprs_sexp)?;
+
+        let plan =
+            SedonaDBExprFactory::select(self.inner.clone().into_unoptimized_plan(), exprs, vec![])?;
+        let inner = DataFrame::new(ctx.inner.ctx.state(), plan);
+        Ok(new_data_frame(inner, self.runtime.clone()))
+    }
 }