add utils for fns that we can reuse at various places

Author: nevi-me

src/dataframe.rs

@@ -1,4 +1,5 @@
 use crate::table::Column;
+use crate::utils;
 use arrow::array;
 use arrow::array::{Array, ArrayRef};
 use arrow::array_data::ArrayDataBuilder;
@@ -13,28 +14,6 @@ use std::sync::Arc;
 
 use crate::error::DataFrameError;
 
-fn make_array(data: ArrayDataRef) -> ArrayRef {
-    // TODO: here data_type() needs to clone the type - maybe add a type tag enum to
-    // avoid the cloning.
-    match data.data_type().clone() {
-        DataType::Boolean => Arc::new(array::BooleanArray::from(data)) as ArrayRef,
-        DataType::Int8 => Arc::new(array::Int8Array::from(data)) as ArrayRef,
-        DataType::Int16 => Arc::new(array::Int16Array::from(data)) as ArrayRef,
-        DataType::Int32 => Arc::new(array::Int32Array::from(data)) as ArrayRef,
-        DataType::Int64 => Arc::new(array::Int64Array::from(data)) as ArrayRef,
-        DataType::UInt8 => Arc::new(array::UInt8Array::from(data)) as ArrayRef,
-        DataType::UInt16 => Arc::new(array::UInt16Array::from(data)) as ArrayRef,
-        DataType::UInt32 => Arc::new(array::UInt32Array::from(data)) as ArrayRef,
-        DataType::UInt64 => Arc::new(array::UInt64Array::from(data)) as ArrayRef,
-        DataType::Float32 => Arc::new(array::Float32Array::from(data)) as ArrayRef,
-        DataType::Float64 => Arc::new(array::Float64Array::from(data)) as ArrayRef,
-        DataType::Utf8 => Arc::new(array::BinaryArray::from(data)) as ArrayRef,
-        DataType::List(_) => Arc::new(array::ListArray::from(data)) as ArrayRef,
-        DataType::Struct(_) => Arc::new(array::StructArray::from(data)) as ArrayRef,
-        dt => panic!("Unexpected data type {:?}", dt),
-    }
-}
-
 //impl From<&ArrayRef> for &PrimitiveArray<BooleanType> {
 //    fn from(array: &ArrayRef) -> Self {
 //        array.as_any().downcast_ref::<BooleanArray>().unwrap()
@@ -219,7 +198,7 @@ impl DataFrame {
     //                     )
     //                     .build()
     //             })
-    //             .map(|col| make_array(col))
+    //             .map(|col| utils::make_array(col))
     //             .collect(),
     //     )
     // }

src/lib.rs

@@ -4,8 +4,9 @@
 #![allow(dead_code)]
 #![feature(test)]
 
-mod dataframe;
-mod error;
-mod functions;
-mod io;
-mod table;
+pub mod dataframe;
+pub mod error;
+pub mod functions;
+pub mod io;
+pub mod table;
+pub mod utils;

src/utils.rs

@@ -0,0 +1,29 @@
+use crate::table::Column;
+use arrow::array;
+use arrow::array::{Array, ArrayRef};
+// use arrow::array_data::ArrayDataBuilder;
+use arrow::array_data::ArrayDataRef;
+use arrow::datatypes::*;
+use std::sync::Arc;
+
+pub fn make_array(data: ArrayDataRef) -> ArrayRef {
+    // TODO: here data_type() needs to clone the type - maybe add a type tag enum to
+    // avoid the cloning.
+    match data.data_type().clone() {
+        DataType::Boolean => Arc::new(array::BooleanArray::from(data)) as ArrayRef,
+        DataType::Int8 => Arc::new(array::Int8Array::from(data)) as ArrayRef,
+        DataType::Int16 => Arc::new(array::Int16Array::from(data)) as ArrayRef,
+        DataType::Int32 => Arc::new(array::Int32Array::from(data)) as ArrayRef,
+        DataType::Int64 => Arc::new(array::Int64Array::from(data)) as ArrayRef,
+        DataType::UInt8 => Arc::new(array::UInt8Array::from(data)) as ArrayRef,
+        DataType::UInt16 => Arc::new(array::UInt16Array::from(data)) as ArrayRef,
+        DataType::UInt32 => Arc::new(array::UInt32Array::from(data)) as ArrayRef,
+        DataType::UInt64 => Arc::new(array::UInt64Array::from(data)) as ArrayRef,
+        DataType::Float32 => Arc::new(array::Float32Array::from(data)) as ArrayRef,
+        DataType::Float64 => Arc::new(array::Float64Array::from(data)) as ArrayRef,
+        DataType::Utf8 => Arc::new(array::BinaryArray::from(data)) as ArrayRef,
+        DataType::List(_) => Arc::new(array::ListArray::from(data)) as ArrayRef,
+        DataType::Struct(_) => Arc::new(array::StructArray::from(data)) as ArrayRef,
+        dt => panic!("Unexpected data type {:?}", dt),
+    }
+}