Add set_bit to BooleanBufferBuilder to allow mutating bit in index (#383)
* Add set_bit to BooleanBufferBuilder to allow mutating bits in the builder
* Fix tests
* Update builder.rs
* Update builder.rs
* Fix clippy failures
Co-authored-by: Boaz Berman <boaz@codota.com>
diff --git a/arrow/src/array/builder.rs b/arrow/src/array/builder.rs
index a9e7fe2..71fd9a9 100644
--- a/arrow/src/array/builder.rs
+++ b/arrow/src/array/builder.rs
@@ -303,6 +303,15 @@
}
#[inline]
+ pub fn set_bit(&mut self, index: usize, v: bool) {
+ if v {
+ bit_util::set_bit(self.buffer.as_mut(), index);
+ } else {
+ bit_util::unset_bit(self.buffer.as_mut(), index);
+ }
+ }
+
+ #[inline]
pub fn is_empty(&self) -> bool {
self.len == 0
}
@@ -2266,7 +2275,7 @@
}
#[test]
- fn test_write_bytes() {
+ fn test_boolean_buffer_builder_write_bytes() {
let mut b = BooleanBufferBuilder::new(4);
b.append(false);
b.append(true);
@@ -2286,6 +2295,83 @@
}
#[test]
+ fn test_boolean_buffer_builder_unset_first_bit() {
+ let mut buffer = BooleanBufferBuilder::new(4);
+ buffer.append(true);
+ buffer.append(true);
+ buffer.append(false);
+ buffer.append(true);
+ buffer.set_bit(0, false);
+ assert_eq!(buffer.len(), 4);
+ assert_eq!(buffer.finish().as_slice(), &[0b1010_u8]);
+ }
+
+ #[test]
+ fn test_boolean_buffer_builder_unset_last_bit() {
+ let mut buffer = BooleanBufferBuilder::new(4);
+ buffer.append(true);
+ buffer.append(true);
+ buffer.append(false);
+ buffer.append(true);
+ buffer.set_bit(3, false);
+ assert_eq!(buffer.len(), 4);
+ assert_eq!(buffer.finish().as_slice(), &[0b0011_u8]);
+ }
+
+ #[test]
+ fn test_boolean_buffer_builder_unset_an_inner_bit() {
+ let mut buffer = BooleanBufferBuilder::new(5);
+ buffer.append(true);
+ buffer.append(true);
+ buffer.append(false);
+ buffer.append(true);
+ buffer.set_bit(1, false);
+ assert_eq!(buffer.len(), 4);
+ assert_eq!(buffer.finish().as_slice(), &[0b1001_u8]);
+ }
+
+ #[test]
+ fn test_boolean_buffer_builder_unset_several_bits() {
+ let mut buffer = BooleanBufferBuilder::new(5);
+ buffer.append(true);
+ buffer.append(true);
+ buffer.append(true);
+ buffer.append(false);
+ buffer.append(true);
+ buffer.set_bit(1, false);
+ buffer.set_bit(2, false);
+ assert_eq!(buffer.len(), 5);
+ assert_eq!(buffer.finish().as_slice(), &[0b10001_u8]);
+ }
+
+ #[test]
+ fn test_boolean_buffer_builder_unset_several_bits_bigger_than_one_byte() {
+ let mut buffer = BooleanBufferBuilder::new(16);
+ buffer.append_n(10, true);
+ buffer.set_bit(0, false);
+ buffer.set_bit(3, false);
+ buffer.set_bit(9, false);
+ assert_eq!(buffer.len(), 10);
+ assert_eq!(buffer.finish().as_slice(), &[0b11110110_u8, 0b01_u8]);
+ }
+
+ #[test]
+ fn test_boolean_buffer_builder_flip_several_bits_bigger_than_one_byte() {
+ let mut buffer = BooleanBufferBuilder::new(16);
+ buffer.append_n(5, true);
+ buffer.append_n(5, false);
+ buffer.append_n(5, true);
+ buffer.set_bit(0, false);
+ buffer.set_bit(3, false);
+ buffer.set_bit(9, false);
+ buffer.set_bit(6, true);
+ buffer.set_bit(14, true);
+ buffer.set_bit(13, false);
+ assert_eq!(buffer.len(), 15);
+ assert_eq!(buffer.finish().as_slice(), &[0b01010110_u8, 0b1011100_u8]);
+ }
+
+ #[test]
fn test_boolean_array_builder_append_slice() {
let arr1 =
BooleanArray::from(vec![Some(true), Some(false), None, None, Some(false)]);
diff --git a/arrow/src/util/bit_util.rs b/arrow/src/util/bit_util.rs
index 4cfa816..7298eb3 100644
--- a/arrow/src/util/bit_util.rs
+++ b/arrow/src/util/bit_util.rs
@@ -62,7 +62,7 @@
(*data.add(i >> 3) & BIT_MASK[i & 7]) != 0
}
-/// Sets bit at position `i` for `data`
+/// Sets bit at position `i` for `data` to 1
#[inline]
pub fn set_bit(data: &mut [u8], i: usize) {
data[i >> 3] |= BIT_MASK[i & 7];
