Method finish

datafusion/functions/src/strings.rs:136–161

Finalize the builder into a concrete [`StringArray`]. # Errors Returns an error when: - the provided `null_buffer` is not the same length as the `offsets_buffer`.

(self, null_buffer: Option<NullBuffer>)

    ///
    /// - the provided `null_buffer` is not the same length as the `offsets_buffer`.
    pub fn finish(self, null_buffer: Option<NullBuffer>) -> Result<StringArray> {
        let row_count = self.offsets_buffer.len() / size_of::<i32>() - 1;
        if let Some(ref null_buffer) = null_buffer
            && null_buffer.len() != row_count
        {
            return internal_err!(
                "Null buffer and offsets buffer must be the same length"
            );
        }
        let array_builder = ArrayDataBuilder::new(DataType::Utf8)
            .len(row_count)
            .add_buffer(self.offsets_buffer.into())
            .add_buffer(self.value_buffer.into())
            .nulls(null_buffer);
        if self.tainted {
            // Raw binary arrays with possible invalid utf-8 were used,
            // so let ArrayDataBuilder perform validation
            let array_data = array_builder.build()?;
            Ok(StringArray::from(array_data))
        } else {
            // SAFETY: all data that was appended was valid UTF8 and the values
            // and offsets were created correctly
            let array_data = unsafe { array_builder.build_unchecked() };
            Ok(StringArray::from(array_data))
        }
    }
}

/// Builder used by `concat`/`concat_ws` to assemble a [`StringViewArray`] one