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The following commit(s) were added to refs/heads/main by this push:
new 8dad535a4a feat: add `append_buffer` for `NullBufferBuilder` (#7308)
8dad535a4a is described below
commit 8dad535a4a7481c5f74f98cd571798fa7e87d233
Author: Raz Luvaton <[email protected]>
AuthorDate: Wed Mar 19 19:59:11 2025 +0200
feat: add `append_buffer` for `NullBufferBuilder` (#7308)
* feat: add `append_buffer` for `NullBufferBuilder`
* test: added test
---
arrow-buffer/src/builder/null.rs | 63 ++++++++++++++++++++++++++++++++++++++++
1 file changed, 63 insertions(+)
diff --git a/arrow-buffer/src/builder/null.rs b/arrow-buffer/src/builder/null.rs
index 3c762bdebc..e6f426615b 100644
--- a/arrow-buffer/src/builder/null.rs
+++ b/arrow-buffer/src/builder/null.rs
@@ -179,6 +179,20 @@ impl NullBufferBuilder {
}
}
+ /// Append [`NullBuffer`] to this [`NullBufferBuilder`]
+ ///
+ /// This is useful when you want to concatenate two null buffers.
+ pub fn append_buffer(&mut self, buffer: &NullBuffer) {
+ if buffer.null_count() > 0 {
+ self.materialize_if_needed();
+ }
+ if let Some(buf) = self.bitmap_builder.as_mut() {
+ buf.append_buffer(buffer.inner())
+ } else {
+ self.len += buffer.len();
+ }
+ }
+
/// Builds the null buffer and resets the builder.
/// Returns `None` if the builder only contains `true`s.
pub fn finish(&mut self) -> Option<NullBuffer> {
@@ -339,4 +353,53 @@ mod tests {
builder.truncate(1);
assert_eq!(builder.len(), 1);
}
+
+ #[test]
+ fn test_append_buffers() {
+ let mut builder = NullBufferBuilder::new(0);
+ let buffer1 = NullBuffer::from(&[true, true]);
+ let buffer2 = NullBuffer::from(&[true, true, false]);
+
+ builder.append_buffer(&buffer1);
+ builder.append_buffer(&buffer2);
+
+ assert_eq!(builder.as_slice().unwrap(), &[0b01111_u8]);
+ }
+
+ #[test]
+ fn test_append_buffers_with_unaligned_length() {
+ let mut builder = NullBufferBuilder::new(0);
+ let buffer = NullBuffer::from(&[true, true, false, true, false]);
+ builder.append_buffer(&buffer);
+ assert_eq!(builder.as_slice().unwrap(), &[0b01011_u8]);
+
+ let buffer = NullBuffer::from(&[false, false, true, true, true, false,
false]);
+ builder.append_buffer(&buffer);
+ assert_eq!(builder.as_slice().unwrap(), &[0b10001011_u8, 0b0011_u8]);
+ }
+
+ #[test]
+ fn test_append_empty_buffer() {
+ let mut builder = NullBufferBuilder::new(0);
+ let buffer = NullBuffer::from(&[true, true, false, true]);
+ builder.append_buffer(&buffer);
+ assert_eq!(builder.as_slice().unwrap(), &[0b1011_u8]);
+
+ let buffer = NullBuffer::from(&[]);
+ builder.append_buffer(&buffer);
+
+ assert_eq!(builder.as_slice().unwrap(), &[0b1011_u8]);
+ }
+
+ #[test]
+ fn test_should_not_materialize_when_appending_all_valid_buffers() {
+ let mut builder = NullBufferBuilder::new(0);
+ let buffer = NullBuffer::from(&[true; 10]);
+ builder.append_buffer(&buffer);
+
+ let buffer = NullBuffer::from(&[true; 2]);
+ builder.append_buffer(&buffer);
+
+ assert_eq!(builder.finish(), None);
+ }
}
