Test changing boolean kernels to use new bit op function

Author: alamb

arrow-buffer/src/buffer/immutable.rs

@@ -1013,7 +1013,8 @@ mod tests {
 
         let assert_preserved = |offset: usize, len: usize| {
             let new_buf = buf.bit_slice(offset, len);
-            assert_eq!(new_buf.len(), bit_util::ceil(len, 8));
+            println!("assert_preserved: offset: {offset}, len: {len}, new_buf_len: {}", new_buf.len());
+            assert_eq!(new_buf.len(), bit_util::ceil(len, 8), "Expected len {} but got {}", bit_util::ceil(len, 8), new_buf.len());
 
             // if the offset is not byte-aligned, we have to create a deep copy to a new buffer
             // (since the `offset` value inside a Buffer is byte-granular, not bit-granular), so
@@ -1034,6 +1035,7 @@ mod tests {
             for l in (o..=64).map(|l| l - o) {
                 // and we just want to make sure every one of these keeps its offset and length
                 // when neeeded
+                println!("testing offset {o}, len {l}");
                 assert_preserved(o, l);
             }
         }

arrow-buffer/src/buffer/ops.rs

@@ -72,7 +72,8 @@ pub fn bitwise_bin_op_helper<F>(
 where
     F: FnMut(u64, u64) -> u64,
 {
-    let mut result = left.as_slice().to_vec();
+    let len_bytes = ceil(len_in_bits + left_offset_in_bits, 8);
+    let mut result = left[0..len_bytes].to_vec();
     bitwise_binary_op(
         &mut result,
         left_offset_in_bits,
@@ -96,7 +97,13 @@ pub fn bitwise_unary_op_helper<F>(
 where
     F: FnMut(u64) -> u64,
 {
-    let mut result = left.to_vec();
+    println!("------ bitwise_unary_op_helper ----");
+    println!("offset_in_bits: {}", offset_in_bits);
+    println!("len_in_bits: {}", len_in_bits);
+    let len_bytes = ceil(len_in_bits + offset_in_bits, 8);
+    println!("len_bytes: {}", len_bytes);
+
+    let mut result = left[0..len_bytes].to_vec();
 
     bitwise_unary_op(&mut result, offset_in_bits, len_in_bits, op);
     result.into()

arrow-buffer/src/util/bit_util.rs

@@ -503,7 +503,7 @@ impl<'a> U64UnalignedSlice<'a> {
         // 1. Prepare the buffers
         let left_buffer_mut: &mut [u8] = {
             let last_offset = self::ceil(offset_in_bits + len_in_bits, 8);
-            assert!(last_offset <= buffer.len());
+            assert!(last_offset <= buffer.len(), "last_offset {last_offset} exceeds buffer length {}", buffer.len());
 
             let byte_offset = offset_in_bits / 8;