tests/testthat/test-cloneEnv-cycle.R

In nlmixr2est: Nonlinear Mixed Effects Models in Population PK/PD, Estimation Routines

nmTest({
  test_that(".cloneEnv() handles circular environment references without infinite recursion", {
    # Regression test: .cloneEnv() used to recurse forever on circular environment graphs.

    # a -> b -> a  (two-node cycle)
    .a <- new.env(parent = emptyenv())
    .b <- new.env(parent = emptyenv())
    .a$child <- .b
    .b$parent <- .a
    .a$val <- 42L
    .b$val <- 7L

    .cl <- nlmixr2est:::.cloneEnv(.a)

    expect_true(is.environment(.cl))
    expect_false(identical(.cl, .a))          # a real clone, not the original
    expect_equal(.cl$val, 42L)
    expect_true(is.environment(.cl$child))
    expect_false(identical(.cl$child, .b))    # the nested env is cloned too
    expect_equal(.cl$child$val, 7L)
    # cycle is rebuilt pointing at the clone, not duplicated
    expect_identical(.cl$child$parent, .cl)

    # a direct self-reference must also terminate
    .s <- new.env(parent = emptyenv())
    .s$self <- .s
    .s$y <- "z"
    .cs <- nlmixr2est:::.cloneEnv(.s)
    expect_equal(.cs$y, "z")
    expect_identical(.cs$self, .cs)
  })
})