tests/testthat/test-expect_true_false_linter.R

In lintr: A 'Linter' for R Code

test_that("expect_true_false_linter skips allowed usages", {
  linter <- expect_true_false_linter()
  # expect_true is a scalar test; testing logical vectors with expect_equal is OK
  expect_no_lint("expect_equal(x, c(TRUE, FALSE))", linter)

  expect_no_lint("expect_equal(x, y, ignore_attr = TRUE)")

  expect_no_lint("42 %>% expect_identical(42, ignore_attr = TRUE)", linter)
  expect_no_lint("42 %>% expect_identical(42, TRUE)", linter)

  skip_if_not_r_version("4.1.0")
  expect_no_lint("42 |> expect_identical(42, ignore_attr = TRUE)", linter)
})

test_that("expect_true_false_linter blocks simple disallowed usages", {
  linter <- expect_true_false_linter()
  lint_msg <- rex::rex("expect_true(x) is better than expect_equal(x, TRUE)")

  expect_lint("expect_equal(foo(x), TRUE)", lint_msg, linter)

  # expect_identical is treated the same as expect_equal
  expect_lint(
    "testthat::expect_identical(x, FALSE)",
    rex::rex("expect_false(x) is better than expect_identical(x, FALSE)"),
    linter
  )

  # also caught when TRUE/FALSE is the first argument
  expect_lint("expect_equal(TRUE, foo(x))", lint_msg, linter)

  expect_lint("42 %T>% expect_equal(TRUE)", lint_msg, linter)

  skip_if_not_r_version("4.1.0")
  expect_lint("42 |> expect_equal(TRUE)", lint_msg, linter)
})

test_that("lints vectorize", {
  expect_lint(
    trim_some("{
      expect_equal(x, TRUE)
      expect_equal(x, FALSE)
    }"),
    list(
      list("expect_true", line_number = 2L),
      list("expect_false", line_number = 3L)
    ),
    expect_true_false_linter()
  )
})