library(testthat)

describe("promise_all", {
  it("preserves element ordering", {
    a <- resolve_later(1, 0.5)
    b <- resolve_later(2, 0.3)
    c <- resolve_later(3, 0.1)

    x <- promise_all(.list = list(a = a, b = b, c = c))
    expect_identical(extract(x), list(a = 1, b = 2, c = 3))
  })

  it("Handles NULLs correctly", {
    x <- promise_all(
      promise_resolve(NULL),
      promise_resolve(NULL),
      promise_resolve(NULL)
    )
    expect_identical(extract(x), list(NULL, NULL, NULL))

    x <- promise_all(
      a = promise_resolve(NULL),
      b = promise_resolve(NULL),
      c = promise_resolve(NULL)
    )
    expect_identical(extract(x), list(a = NULL, b = NULL, c = NULL))
  })

  it("handles duplicate names correctly", {
    x <- resolve_later(1, 0.5)
    y <- resolve_later(2, 0.3)
    z <- resolve_later(3, 0.1)

    x <- promise_all(.list = list(a = x, a = y, a = z))
    expect_identical(extract(x), list(a = 1, a = 2, a = 3))
  })
})