tests/testthat/test-whitespace_linter.R

In lintr: A 'Linter' for R Code

test_that("whitespace_linter skips allowed usages", {
  linter <- whitespace_linter()

  expect_lint("blah", NULL, linter)
  expect_lint("  blah", NULL, linter)
  expect_lint("  blah", NULL, linter)
  expect_lint("#\tblah", NULL, linter)
})

test_that("whitespace_linter skips allowed tab usages inside strings", {
  linter <- whitespace_linter()

  expect_lint(
    'lint_msg <- "dont flag tabs if\tthey are inside a string."',
    NULL,
    linter
  )

  expect_lint(
    'lint_msg <- "dont flag tabs if\n\tthey are inside multiline strings."',
    NULL,
    linter
  )
})

test_that("whitespace_linter blocks disallowed usages", {
  linter <- whitespace_linter()
  lint_msg <- rex::rex("Use spaces to indent, not tabs.")

  expect_lint(
    "\tblah",
    list(message = lint_msg, line_number = 1L, column_number = 1L, ranges = list(c(1L, 1L))),
    linter
  )

  expect_lint(
    "\n\t\t\tblah",
    list(message = lint_msg, line_number = 2L, column_number = 1L),
    linter
  )
})

test_that("whitespace_linter blocks disallowed usages with a pipe", {
  skip_if_not_r_version("4.1.0")

  linter <- whitespace_linter()
  lint_msg <- rex::rex("Use spaces to indent, not tabs.")

  expect_lint(
    "a %>%\n\tb()",
    list(message = lint_msg, line_number = 2L, column_number = 1L, ranges = list(c(1L, 1L))),
    linter
  )

  expect_lint(
    "a |>\n\tb()",
    list(message = lint_msg, line_number = 2L, column_number = 1L, ranges = list(c(1L, 1L))),
    linter
  )
})

test_that("no_tab_linter id deprecated", {
  expect_warning(
    {
      old_linter <- no_tab_linter()
    },
    "Use whitespace_linter instead",
    fixed = TRUE
  )
  expect_lint("  f(a, b, c)", NULL, old_linter)
  expect_lint("\tf(a, b, c)", "not tabs", old_linter)
})