Struct csv_diff::csv_diff::CsvByteDiff

pub struct CsvByteDiff<T: CsvHashTaskSpawner> { /* private fields */ }

Compare two CSVs lazily with each other (for the eager-/blocking-based variant, see CsvByteDiffLocal).

Use this instead of CsvByteDiffLocal, when:

• you own your CSV data and you want to use an Iterator for the differences, so you don’t have to read all differences into memory
• your CSV data structure does not support Seek.

By default, CsvByteDiff uses a rayon thread-pool to compare differences. If you already have an existing rayon thread-pool that you want to use for CsvByteDiff, you can construct it with a builder (see also rayon_thread_pool on CsvByteDiffBuilder). for using an existing rayon thread-pool when creating CsvByteDiff.

Example: create CsvByteDiff with default values and compare two CSVs byte-wise lazily

use csv_diff::{csv_diff::CsvByteDiff, csv::Csv};
use csv_diff::diff_row::{ByteRecordLineInfo, DiffByteRecord};
use std::collections::HashSet;
use std::iter::FromIterator;
// some csv data with a header, where the first column is a unique id
let csv_left = "\
header1,header2,header3\n\
a,b,c";
let csv_right = "\
header1,header2,header3\n\
a,b,d";

let csv_diff = CsvByteDiff::new()?;

let mut diff_iterator = csv_diff.diff(
    Csv::with_reader(csv_left.as_bytes()),
    Csv::with_reader(csv_right.as_bytes()),
);

let diff_row_actual = diff_iterator
    .next()
    .ok_or("Expected a difference between the two CSVs, but got none".to_string())??;

let diff_row_expected = DiffByteRecord::Modify {
    delete: ByteRecordLineInfo::new(csv::ByteRecord::from(vec!["a", "b", "c"]), 2),
    add: ByteRecordLineInfo::new(csv::ByteRecord::from(vec!["a", "b", "d"]), 2),
    field_indices: vec![2],
};

assert_eq!(diff_row_actual, diff_row_expected);

Ok(())

Implementations

impl CsvByteDiff<CsvHashTaskSpawnerRayon>

pub fn new() -> Result<Self, CsvDiffNewError>

impl<T> CsvByteDiff<T>where
    T: CsvHashTaskSpawner,

pub fn diff<R: Read + Send + 'static>(
    &self,
    csv_left: Csv<R>,
    csv_right: Csv<R>
) -> DiffByteRecordsIterator

Trait Implementations

impl<T: Debug + CsvHashTaskSpawner> Debug for CsvByteDiff<T>

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.