@electric-sql/d2mini/tests/operators/consolidate.test.ts

D2Mini is a minimal implementation of Differential Dataflow for performing in-memory incremental view maintenance.

import { describe, test, expect } from 'vitest'
import { D2 } from '../../src/d2.js'
import { MultiSet } from '../../src/multiset.js'
import { consolidate } from '../../src/operators/consolidate.js'
import { output } from '../../src/operators/output.js'

describe('Operators', () => {
  describe('Consolidate operation', () => {
    testConsolidate()
  })
})

function testConsolidate() {
  test('basic consolidate operation', () => {
    const graph = new D2()
    const input = graph.newInput<number>()
    const messages: MultiSet<number>[] = []

    input.pipe(
      consolidate(),
      output((message) => {
        messages.push(message)
      }),
    )

    graph.finalize()

    input.sendData(
      new MultiSet([
        [1, 1],
        [2, 1],
      ]),
    )
    input.sendData(
      new MultiSet([
        [3, 1],
        [4, 1],
      ]),
    )
    input.sendData(
      new MultiSet([
        [3, 2],
        [2, -1],
      ]),
    )
    graph.run()

    const data = messages.map((m) => m.getInner())

    expect(data).toEqual([
      [
        [1, 1],
        [3, 3],
        [4, 1],
      ],
    ])
  })

  test('consolidate with all removed', () => {
    const graph = new D2()
    const input = graph.newInput<number>()
    const messages: MultiSet<number>[] = []

    input.pipe(
      consolidate(),
      output((message) => {
        messages.push(message)
      }),
    )

    graph.finalize()

    input.sendData(
      new MultiSet([
        [1, 1],
        [2, 2],
      ]),
    )
    input.sendData(
      new MultiSet([
        [1, -1],
        [2, -2],
      ]),
    )
    graph.run()

    const data = messages.map((m) => m.getInner())

    expect(data).toEqual([])
  })

  test('consolidate with multiple batches', () => {
    const graph = new D2()
    const input = graph.newInput<number>()
    const messages: MultiSet<number>[] = []

    input.pipe(
      consolidate(),
      output((message) => {
        messages.push(message)
      }),
    )

    graph.finalize()

    input.sendData(
      new MultiSet([
        [1, 1],
        [2, 1],
      ]),
    )
    graph.run()

    input.sendData(
      new MultiSet([
        [2, 1],
        [3, 1],
      ]),
    )
    graph.run()

    const data = messages.map((m) => m.getInner())

    expect(data).toEqual([
      [
        [1, 1],
        [2, 1],
      ],
      [
        [2, 1],
        [3, 1],
      ],
    ])
  })
}