tests/testthat/test-vroom.R

In vroom: Read and Write Rectangular Text Data Quickly

test_that("vroom can read a tsv", {
  test_vroom("a\tb\tc\n1\t2\t3\n", delim = "\t",
    equals = tibble::tibble(a = 1, b = 2, c = 3)
  )
})

test_that("vroom can read a csv", {
  test_vroom("a,b,c\n1,2,3\n", delim = ",",
    equals = tibble::tibble(a = 1, b = 2, c = 3)
  )
})

test_that("vroom guesses columns with NAs", {
  test_vroom("a,b,c\nNA,2,3\n4,5,6\n", delim = ",",
    equals = tibble::tibble(a = c(NA, 4), b = c(2, 5), c = c(3, 6))
  )

  test_vroom("a,b,c\nfoo,2,3\n4,5,6\n", delim = ",", na = "foo",
    equals = tibble::tibble(a = c(NA, 4), b = c(2, 5), c = c(3, 6))
  )

  test_vroom("a,b,c\nfoo,2,3\n4.0,5,6\n", delim = ",", na = "foo",
    equals = tibble::tibble(a = c(NA, 4), b = c(2, 5), c = c(3, 6))
  )

  test_vroom("a,b,c\nfoo,2,3\nbar,5,6\n", delim = ",", na = "foo",
    equals = tibble::tibble(a = c(NA, "bar"), b = c(2, 5), c = c(3, 6))
  )
})

test_that("vroom can trim whitespace", {
  test_vroom('a,b,c\n foo ,  bar  ,baz\n', delim = ",",
    equals = tibble::tibble(a = "foo", b = "bar", c = "baz")
  )

  test_vroom('a,b,c\n\tfoo\t,\t\tbar\t\t,baz\n', delim = ",",
    equals = tibble::tibble(a = "foo", b = "bar", c = "baz")
  )

  # whitespace trimmed before quotes
  test_vroom('a,b,c\n "foo" ,  "bar"  ,"baz"\n', delim = ",",
    equals = tibble::tibble(a = "foo", b = "bar", c = "baz")
  )

  # whitespace trimmed inside quotes
  test_vroom('a,b,c\n"foo  ","  bar","\t\tbaz"\n', delim = ",",
    equals = tibble::tibble(a = "foo", b = "bar", c = "baz")
  )
})

test_that("vroom can read files with quotes", {
  test_vroom('"a","b","c"\n"foo","bar","baz"\n', delim = ",",
    equals = tibble::tibble(a = "foo", b = "bar", c = "baz")
  )

  test_vroom('"a","b","c"\n",foo","bar","baz"\n', delim = ",",
    equals = tibble::tibble(a = ",foo", b = "bar", c = "baz")
  )

  test_vroom("'a','b','c'\n',foo','bar','baz'\n", delim = ",", quote = "'",
    equals = tibble::tibble(a = ",foo", b = "bar", c = "baz")
  )
})

test_that("vroom escapes double quotes", {
  test_vroom('"a","b","c"\n"""fo""o","b""""ar","baz"""\n', delim = ",",
    equals = tibble::tibble(a = "\"fo\"o", b = "b\"\"ar", c = "baz\"")
  )
})

test_that("vroom escapes backslashes", {
  test_vroom('a,b,c\n\\,foo,\\"ba\\"r,baz\\"\n', delim = ",", escape_backslash = TRUE,
    equals = tibble::tibble(a = ",foo", b = "\"ba\"r", c = "baz\"")
  )
})

test_that("vroom ignores leading whitespace", {
  test_vroom('\n\n   \t \t\n  \n\na,b,c\n1,2,3\n', delim = ",",
    equals = tibble::tibble(a = 1, b = 2, c = 3)
  )
})

test_that("vroom ignores comments", {
  test_vroom('\n\n \t #a,b,c\na,b,c\n1,2,3\n', delim = ",", comment = "#",
    equals = tibble::tibble(a = 1, b = 2, c = 3)
  )
})

test_that("vroom respects skip", {
  test_vroom('#a,b,c\na,b,c\n1,2,3\n', delim = ",", skip = 1,
    equals = tibble::tibble(a = 1, b = 2, c = 3)
  )

  test_vroom('#a,b,c\na,b,c\n1,2,3\n', delim = ",", skip = 1, comment = "#",
    equals = tibble::tibble(a = 1, b = 2, c = 3)
  )

  test_vroom('#a,b,c\nasdfasdf\na,b,c\n1,2,3\n', delim = ",", skip = 2, comment = "#",
    equals = tibble::tibble(a = 1, b = 2, c = 3)
  )

  test_vroom('\n\n#a,b,c\nasdfasdf\na,b,c\n1,2,3\n', delim = ",", skip = 4, comment = "#",
    equals = tibble::tibble(a = 1, b = 2, c = 3)
  )
})

test_that("vroom respects col_types", {
  test_vroom('a,b,c\n1,2,3\n', delim = ",", col_types = "idc",
    equals = tibble::tibble(a = 1L, b = 2, c = "3")
  )

  test_vroom('a,b,c,d\nT,2,3,4\n', delim = ",", col_types = "lfc_",
    equals = tibble::tibble(a = TRUE, b = factor(2), c = "3")
  )
})

test_that("vroom handles UTF byte order marks", {
  # UTF-8
  expect_equal(
    vroom(as.raw(c(0xef, 0xbb, 0xbf, # BOM
                0x41, # A
                0x0A # newline
             )),
         delim = "\n",
         col_names = FALSE,
         col_types = list()
    )[[1]],
    "A")

  # UTF-16 Big Endian
  expect_equal(
    vroom(as.raw(c(0xfe, 0xff, # BOM
                0x41, # A
                0x0A # newline
             )),
         delim = "\n",
         col_names = FALSE,
         col_types = list()
    )[[1]],
    "A")

  # UTF-16 Little Endian
  expect_equal(
    vroom(as.raw(c(0xff, 0xfe, # BOM
                0x41, # A
                0x0A # newline
             )),
         delim = "\n",
         col_names = FALSE,
         col_types = list()
    )[[1]],
    "A")

  # UTF-32 Big Endian
  expect_equal(
    vroom(as.raw(c(0x00, 0x00, 0xfe, 0xff, # BOM
                0x41, # A
                0x0A # newline
             )),
         delim = "\n",
         col_names = FALSE,
         col_types = list()
    )[[1]],
    "A")

  # UTF-32 Little Endian
  expect_equal(
    vroom(as.raw(c(0xff, 0xfe, 0x00, 0x00, # BOM
                0x41, # A
                0x0A # newline
             )),
         delim = "\n",
         col_names = FALSE,
         col_types = list()
    )[[1]],
    "A")
})

test_that("vroom handles vectors shorter than the UTF byte order marks", {
  skip_on_os("solaris")

  expect_equal(
    charToRaw(vroom(as.raw(c(0xef, 0xbb, 0x0A)), delim = "\n", col_names = FALSE, col_types = list())[[1]]),
    as.raw(c(0xef, 0xbb))
  )

  expect_equal(
    charToRaw(vroom(as.raw(c(0xfe, 0x0A)), delim = "\n", col_names = FALSE, col_types = list())[[1]]),
    as.raw(c(0xfe))
  )

  expect_equal(
    charToRaw(vroom(as.raw(c(0xff, 0x0A)), delim = "\n", col_names = FALSE, col_types = list())[[1]]),
    as.raw(c(0xff))
  )
})

test_that("vroom handles windows newlines", {

  expect_equal(
    vroom(I("a\tb\r\n1\t2\r\n"), trim_ws = FALSE, col_types = list())[[1]],
    1
  )
})

test_that("vroom can read a file with only headers", {
  test_vroom("a\n",
    equals = tibble::tibble(a = character())
  )

  test_vroom("a,b,c\n", delim = ",",
    equals = tibble::tibble(a = character(), b = character(), c = character())
  )
})

test_that("vroom can read an empty file", {
  test_vroom("\n",
    equals = tibble::tibble()
  )

  f <- tempfile()
  file.create(f)
  on.exit(unlink(f))

  capture.output(type = "message",
    expect_equal(vroom(f, col_types = list()), tibble::tibble())
  )

  capture.output(type = "message",
    expect_equal(vroom(f, col_names = FALSE, col_types = list()), tibble::tibble())
  )

  expect_equal(vroom(character(), col_types = list()), tibble::tibble())
})

test_that("vroom_examples() returns the example files", {
  expect_equal(vroom_examples(), list.files(system.file("extdata", package = "vroom")))
})

test_that("vroom_example() returns a single example files", {
  expect_equal(vroom_example("mtcars.csv"), system.file("extdata", "mtcars.csv", package = "vroom"))
})

test_that("subsets work", {
  res <- vroom(I("1\n2\n3\n4\n5\n6\n7\n8\n9\n10\n11\n12\n13\n14"), delim = "\t", col_names = FALSE, col_types = list())
  expect_equal(head(res[[1]]), c(1:6))
  expect_equal(tail(res[[1]]), c(9:14))

  expect_equal(tail(res[[1]][3:8]), c(3:8))
})

test_that("n_max works with normal files", {
    expect_equal(
      NROW(vroom(vroom_example("mtcars.csv"), n_max = 2, col_types = list())),
      2
    )

    # headers don't count
    expect_equal(
      NROW(vroom(vroom_example("mtcars.csv"), n_max = 2, col_names = FALSE, col_types = list())),
      2
    )

    # Zero rows with headers should just have the headers
    expect_equal(
      dim(vroom(vroom_example("mtcars.csv"), n_max = 0, col_types = list())),
      c(0, 12)
    )

    # If you don't read the header or any rows it must be empty
    expect_equal(
      dim(vroom(vroom_example("mtcars.csv"), n_max = 0, col_names = FALSE, col_types = list())),
      c(0, 0)
    )
})

test_that("n_max works with connections files", {
    expect_equal(
      NROW(vroom(vroom_example("mtcars.csv.gz"), n_max = 2, col_types = list())),
      2
    )

    # headers don't count
    expect_equal(
      NROW(vroom(vroom_example("mtcars.csv.gz"), n_max = 2, col_names = FALSE, col_types = list())),
      2
    )

    # Zero rows with headers should just have the headers
    expect_equal(
      dim(vroom(vroom_example("mtcars.csv.gz"), n_max = 0, col_types = list())),
      c(0, 12)
    )

    # If you don't read the header or any rows it must be empty
    expect_equal(
      dim(vroom(vroom_example("mtcars.csv.gz"), n_max = 0, col_names = FALSE, col_types = list())),
      c(0, 0)
    )
})

test_that("vroom truncates col_names if it is too long", {
  test_vroom("1\n2\n", col_names = c("a", "b"),
    equals = tibble::tibble(a = c(1, 2))
  )
})

test_that("vroom makes additional col_names if it is too short", {
  test_vroom("1,2,3\n4,5,6\n", col_names = c("a", "b"), delim = ",",
    equals = tibble::tibble(a = c(1, 4), b = c(2, 5), X3 = c(3, 6))
  )
})

test_that("vroom reads newlines in data", {
  test_vroom('a\n"1\n2"\n',
  equals = tibble::tibble(a = "1\n2"))
})

test_that("vroom reads headers with embedded newlines", {
  test_vroom("\"Header\nLine Two\"\nValue\n", delim = ",",
    equals = tibble::tibble("Header\nLine Two" = "Value")
  )

  test_vroom("\"Header\",\"Second header\nLine Two\"\nValue,Value2\n", delim = ",",
    equals = tibble::tibble("Header" = "Value", "Second header\nLine Two" = "Value2")
  )
})

test_that("vroom reads headers with embedded newlines 2", {
  test_vroom("\"Header\nLine Two\"\n\"Another line\nto\nskip\"\nValue,Value2\n", skip = 2, col_names = FALSE, delim = ",",
    equals = tibble::tibble("X1" = "Value", "X2" = "Value2")
  )
})

test_that("vroom uses the number of rows when guess_max = Inf", {
  tf <- tempfile()
  df <- tibble::tibble(x = c(1:1000, "foo", 1001))
  vroom_write(df, tf, delim = "\t")

  # The type should be guessed wrong, because the character comes at the end
  expect_warning(res <- vroom(tf, delim = "\t", col_types = list(), altrep = FALSE))
  expect_type(res[["x"]], "double")
  expect_true(is.na(res[["x"]][[NROW(res) - 1]]))

  # The value should exist with guess_max = Inf
  res <- vroom(tf, delim = "\t", guess_max = Inf, col_types = list())
  expect_type(res[["x"]], "character")
  expect_equal(res[["x"]][[NROW(res) - 1]], "foo")
})

test_that("vroom adds columns if a row is too short", {
  test_vroom("a,b,c,d\n1,2\n3,4,5,6\n", delim = ",",
    equals = tibble::tibble("a" = c(1,3), "b" = c(2,4), "c" = c(NA, 5), "d" = c(NA, 6))
  )
})

test_that("vroom removes columns if a row is too long", {
  test_vroom("a,b,c,d\n1,2,3,4,5,6,7\n8,9,10,11\n", delim = ",", col_types = c(d = "c"),
    equals = tibble::tibble("a" = c(1,8), "b" = c(2,9), "c" = c(3, 10), "d" = c("4,5,6,7", "11"))
  )
})

# Figure out a better way to test progress bars...
#test_that("progress bars work", {
  #withr::with_options(c("vroom.show_after" = 0), {
    #expect_output_file(vroom(vroom_example("mtcars.csv"), progress = TRUE), "mtcars-progress")
  #})
#})

test_that("guess_type works with long strings (#74)", {
  expect_s3_class(
    guess_type("https://www.bing.com/search?q=mr+popper%27s+penguins+worksheets+free&FORM=QSRE1"),
    "collector_character"
  )
})

test_that("vroom guesses types if unnamed column types do not match the number of columns", {
  test_vroom(I("a,b\n1,2\n"), delim = ",", col_types = "i",
    equals = tibble::tibble(a = 1L, b = 2L))
})

test_that("column names are properly encoded", {
  skip_on_os("solaris")

  nms <- vroom(I("f\U00F6\U00F6\nbar\n"), delim = "\n", col_types = list())
  expect_equal(Encoding(colnames(nms)), "UTF-8")
})

test_that("Files with windows newlines and missing fields work", {
  test_vroom("a,b,c,d\r\nm,\r\n\r\n", delim = ",", skip_empty_rows = FALSE,
    equals = tibble::tibble(a = c("m", NA), b = c(NA, NA), c = c(NA, NA), d = c(NA, NA))
  )
})

test_that("vroom can read files with no trailing newline", {
  f <- tempfile()
  on.exit(unlink(f))

  writeBin(charToRaw("foo\nbar"), f)
  expect_equal(vroom(f, col_names = FALSE, delim = ",", col_types = list())[[1]], c("foo", "bar"))

  f2 <- tempfile()
  on.exit(unlink(f2), add = TRUE)

  writeBin(charToRaw("foo,bar\n1,2"), f2)
  expect_equal(vroom(f2, delim = ",", col_types = list()), tibble::tibble(foo = 1, bar = 2))
})

test_that("Missing files error with a nice error message", {
  f <- tempfile()
  expect_error(vroom(f, col_types = list()), "does not exist")
  expect_error(vroom("foo", col_types = list()), "does not exist in current working directory")
})

test_that("Can return the spec object", {
  x <- vroom(I("foo,bar\n1,c\n"), col_types = list())
  obj <- spec(x)
  expect_s3_class(obj, "col_spec")
  exp <- as.col_spec(list(foo = "d", bar = "c"))
  exp$delim <- ","
  expect_equal(obj, exp)
})

test_that("vroom handles files with trailing commas, windows newlines, missing a final newline and not null terminated", {
  f <- tempfile()
  on.exit(unlink(f))

  writeChar(paste(collapse = "\r\n", c('foo,bar,', '1,2,')), con = f, eos = NULL)

  expect_message(regexp = "New names",
    expect_equal(
      vroom(f, col_types = list()),
      tibble::tibble(foo = 1, bar = 2, "...3" = NA)
    )
  )
})

test_that("vroom uses the delim if it is specified in the col_types", {
  # if we give a tab delim in the spec there should only be one column
  expect_equal(
    ncol(vroom(I("a,b,c\n1,2,3\n"), col_types = list(.delim = "\t"))),
    1
  )

  # But specifying an explicit delim overrides the spec
  expect_equal(
    ncol(vroom(I("a,b,c\n1,2,3\n"), col_types = list(.delim = "\t"), delim = ",")),
    3
  )

  expect_equal(
    ncol(vroom(I("a,b,c\n1,2,3\n"), col_types = list(.delim = ","), delim = "\t")),
    1
  )
})

test_that("vroom supports NA and NA_integer_ indices", {
  data <- vroom(vroom_example("mtcars.csv"), col_types = list())

  expect_equal(data[NA, 1, drop = TRUE], rep(NA_character_, nrow(data)))
  expect_equal(data[NA_integer_, 1, drop = TRUE], NA_character_)
})

test_that("vroom supports NA and NA_integer_ indices with factors and datetimes", {
  data <- vroom(I("x\ty\nfoo\t2020-01-01 12:00:01"), col_types = "fT")

  expect_equal(data[NA, 1, drop = TRUE], factor(NA, levels = "foo"))
  expect_equal(data[NA, 2, drop = TRUE], .POSIXct(NA_real_, tz = "UTC"))
  expect_equal(data[NA_integer_, 1, drop = TRUE], factor(NA, levels = "foo"))
  expect_equal(data[NA_integer_, 2, drop = TRUE], .POSIXct(NA_real_, tz = "UTC"))
})

test_that("vroom works with windows newlines and files without a trailing newline (#219)", {
  f <- tempfile()
  on.exit(unlink(f))
  writeBin(charToRaw("X,Y\r\n1,12/08/2016\r\n2,05/01/2018"), f)

  res <- vroom(f, col_types = cols(Y = "c"))
  expect_equal(res$Y[[2]], "05/01/2018")
})

test_that("vroom works with `id` and skipped columns", {
  data <- vroom(vroom_example("mtcars.csv"), col_types = c(mpg = "_"), id = "File")

  expect_true(ncol(data) == 12)
  expect_true(names(data)[[1]] == "File")
  expect_false("mpg" %in% names(data))
})

test_that("vroom works with n_max, windows newlines and files larger than the connection buffer", {
  f <- tempfile()
  on.exit(unlink(f))
  writeBin(charToRaw("X,Y\r\n1,2\r\n3342343242312312,442342432423432432\r\n432424324,532432324"), f)

  withr::with_envvar(c("VROOM_CONNECTION_SIZE" = 25),
    res <- vroom(f, delim = ",", n_max = 1, col_types = list())
  )

  expect_equal(res$X, 1)
  expect_equal(res$Y, 2)
})

test_that("subsetting works with both double and integer indexes", {
  x <- vroom(I("X1\nfoo"), delim = ",", col_types = list())
  expect_equal(x$X1[1L], "foo")
  expect_equal(x$X1[1], "foo")
  expect_equal(x$X1[NA_integer_], NA_character_)
  expect_equal(x$X1[NA_real_], NA_character_)
})

test_that("quotes inside fields are ignored", {
  x <- vroom(I("x\nfoo\"bar\nbaz\n"), delim = ",", quote = "\"", col_types = list())
  expect_equal(x$x[[1]], "foo\"bar")
  expect_equal(x$x[[2]], "baz")
})

test_that("quotes at the beginning and end of lines are used", {
  y <- vroom(I("x\n\"foo\"\"bar\"\nbaz\n"), delim = ",", quote = "\"", col_types = list())
  expect_equal(y$x[[1]], "foo\"bar")
  expect_equal(y$x[[2]], "baz")
})

test_that("quotes at delimiters are used", {
  z <- vroom(I("x,y,z\n1,\"foo\"\"bar\",2\n3,baz,4"), delim = ",", quote = "\"", col_types = list())
  expect_equal(z$y[[1]], "foo\"bar")
  expect_equal(z$y[[2]], "baz")
})

test_that("vroom reads files with embedded newlines even when num_threads > 1", {
  tf <- tempfile()
  con <- file(tf, "wb")
  on.exit({
    unlink(tf)
  })
  writeLines(c("x", rep("foo", 1000), '"bar\nbaz"', rep("qux", 1000)), con, sep = "\n")
  close(con)

  res <- vroom(tf, delim = ",", num_threads = 5, col_types = list())
  expect_equal(nrow(res), 1000 + 1 + 1000)
  expect_equal(res$x[[1001]], "bar\nbaz")
})

test_that("multi-character comments are supported", {
  res <- vroom(I("## this is a comment\n# this is not"), delim = "\t", comment = "##", col_names = FALSE, col_types = list())
  expect_equal(res[[1]], "# this is not")
})

test_that("vroom works with quoted fields at the end of a windows newline", {
  f <- tempfile()
  on.exit(unlink(f))
  con <- file(f, "wb")
  writeLines(c('"x"', 1), con, sep = "\r\n")
  close(con)
  res <- vroom(f, delim = ",", col_names = FALSE, col_types = list())
  expect_equal(res[[1]], c("x", 1))
})

test_that("vroom can handle NUL characters in strings", {
  test_vroom(test_path("raw.csv"), delim = ",", progress = FALSE,
    equals = tibble::tibble(abc = "ab", def = "def")
  )
})

test_that("n_max is respected in all cases", {
  expect_equal(dim(vroom(I("x\ty\tz\n1\t2\t3\n4\t5\t6\n"), n_max = 1, col_types = list())), c(1, 3))
})

test_that("comments are ignored regardless of where they appear", {

  out1 <- vroom(I('x\n1#comment'), comment = "#", col_types = "d", delim = ",")
  out2 <- vroom(I('x\n1#comment\n#comment'), comment = "#", col_types = "d", delim = ",")
  out3 <- vroom(I('x\n"1"#comment'), comment = "#", col_types = "d", delim = ",")

  expect_equal(out1$x, 1)
  expect_equal(out2$x, 1)
  expect_equal(out3$x, 1)

  out4 <- vroom(I('x,y\n1,#comment'), comment = "#", delim = ",", col_types = "cc", progress = FALSE, altrep = FALSE)
  expect_equal(out4$y, NA_character_)

  expect_warning(out5 <- vroom(I("x1,x2,x3\nA2,B2,C2\nA3#,B2,C2\nA4,A5,A6"), comment = "#", delim = ",", col_types = "ccc", altrep = FALSE, progress = FALSE))
  expect_warning(out6 <- vroom(I("x1,x2,x3\nA2,B2,C2\nA3,#B2,C2\nA4,A5,A6"), comment = "#", delim = ",", col_types = "ccc", altrep = FALSE, progress = FALSE))
  expect_warning(out7 <- vroom(I("x1,x2,x3\nA2,B2,C2\nA3,#B2,C2\n#comment\nA4,A5,A6"), comment = "#", delim = ",", col_types = "ccc", altrep = FALSE, progress = FALSE))

  chk <- tibble::tibble(
    x1 = c("A2", "A3", "A4"),
    x2 = c("B2", NA_character_, "A5"),
    x3 = c("C2", NA_character_, "A6"))

  expect_true(all.equal(chk, out5, check.attributes = FALSE))
  expect_true(all.equal(chk, out6, check.attributes = FALSE))
  expect_true(all.equal(chk, out7, check.attributes = FALSE))
})

test_that("escaped/quoted comments are ignored", {
  out1 <- vroom(I('x\n\\#'), comment = "#", delim = ",",
    escape_backslash = TRUE, escape_double = FALSE, progress = FALSE, col_types = "c")
  out2 <- vroom(I('x\n"#"'), comment = "#", progress = FALSE, delim = ",", col_types = "c")

  expect_equal(out1$x, "#")
  expect_equal(out2$x, "#")
})

test_that("name repair with custom functions works", {
  add_y <- function(x) {
    paste(x, "y", sep = "_")
  }
  out <- vroom(I("x,y,z\n1,2,3"), col_types = "iii", .name_repair = add_y)
  expect_equal(colnames(out), c("x_y", "y_y", "z_y"))
})

test_that("col_types are based on the final (possibly repaired) column names (#311)", {
  suppressMessages(
    out <- vroom(I("x,\n1,2\n3,4"), delim = ",", col_types = list(x = col_double(), "...2" = col_double()))
  )
  expect_equal(out[["...2"]], c(2, 4))
})

test_that("mismatched column names throw a classed warning", {
  expect_warning(
    vroom(
      I("x,y\n1,2\n3,4\n"),
      col_types = list(
        x = col_double(),
        y = col_double(),
        z = col_double()
      )
    ),
    class = "vroom_mismatched_column_name"
  )
})

test_that("empty files still generate the correct column width and types", {
  out <- vroom(I(""), col_names = c("foo", "bar"), col_types = list())
  expect_equal(nrow(out), 0)
  expect_equal(ncol(out), 2)
  expect_equal(names(out), c("foo", "bar"))
  expect_type(out[[1]], "character")
  expect_type(out[[2]], "character")

  out <- vroom(I(""), col_types = "ii")
  expect_equal(nrow(out), 0)
  expect_equal(ncol(out), 2)
  expect_equal(names(out), c("X1", "X2"))
  expect_type(out[[1]], "integer")
  expect_type(out[[2]], "integer")
})

test_that("leading whitespace effects guessing", {
  out <- vroom(I('a,b,c\n 1,2,3\n'), delim = ",", trim_ws = FALSE, progress = FALSE, col_types = list())
  expect_type(out[[1]], "character")

  out <- vroom(I('a,b,c\n 1,2,3\n'), delim = ",", trim_ws = TRUE, progress = FALSE, col_types = list())
  expect_type(out[[1]], "double")
})

test_that("UTF-16LE encodings can be read", {
  bom <- as.raw(c(255, 254))
  # This is the text.
  text <- "x,y\n\U104371,2\n" # This is a 4 byte UTF-16 character from https://en.wikipedia.org/wiki/UTF-16

  # Converted to UTF-16LE
  text_utf16 <- iconv(text,from="UTF-8", to="UTF-16LE", toRaw = TRUE)[[1]]

  # Write the BOM and the text to a file
  tmp_file_name <- tempfile()
  fd <- file(tmp_file_name, "wb")
  writeBin(bom, fd)
  writeBin(text_utf16, fd)
  close(fd)

  # Whether LE or BE is determined automatically by the BOM
  out <- vroom(tmp_file_name, locale = locale(encoding = "UTF-16"), col_types = "ci")
  expect_equal(out$x, "\U104371")
  expect_equal(out$y, 2)
})

test_that("supports unicode grouping and decimal marks (https://github.com/tidyverse/readr/issues/796)", {
  test_vroom(I("1\u00A0234\u02D95"),
    locale = locale(grouping_mark = "\u00A0", decimal_mark = "\u02D9"),
    col_types = "n", col_names = FALSE, delim = ",",
    equals = tibble::tibble(X1 = 1234.5)
  )
})

test_that("handles quotes within skips", {

  data <- I(paste0(collapse = "\n",
    c("a\tb\tc",
      "1a\t1b\t1c",
      "2a\t2b\t2c\"",
      "3a\t3b\t3c\"",
      "4a\t4b\t4c"
  )))

  test_vroom(data, col_names = c("a", "b", "c"), skip = 2, quote = "", delim = "\t",
    equals = tibble::tibble(
      a = c("2a", "3a", "4a"),
      b = c("2b", "3b", "4b"),
      c = c("2c\"", "3c\"", "4c")
    )
  )

  test_vroom(data, col_names = c("a", "b", "c"), skip = 3, quote = "", delim = "\t",
    equals = tibble::tibble(
      a = c("3a", "4a"),
      b = c("3b", "4b"),
      c = c("3c\"", "4c")
    )
  )

  test_vroom(data, col_names = c("a", "b", "c"), skip = 4, quote = "", delim = "\t",
    equals = tibble::tibble(
      a = c("4a"),
      b = c("4b"),
      c = c("4c")
    )
  )
})

test_that("skipped columns retain their name", {
  test_vroom(I("1,2,3\n4,5,6"), col_names = "x", col_types = "i__",
    equals = tibble::tibble(
      x = c(1L, 4L)
    ))

  test_vroom(I("1,2,3\n4,5,6"), col_names = "y", col_types = "_i_",
    equals = tibble::tibble(
      y = c(2L, 5L)
    ))

  test_vroom(I("1,2,3\n4,5,6"), col_names = "z", col_types = "__i",
    equals = tibble::tibble(
      z = c(3L, 6L)
    ))

  test_vroom(I("1,2,3\n4,5,6"), col_names = c("x", "z"), col_types = "i_i",
    equals = tibble::tibble(
      x = c(1L, 4L),
      z = c(3L, 6L)
    ))
})

test_that("skipped columns retain their name", {
  test_vroom(I("1,2,3\n4,5,6"), col_names = "x", col_types = "i__",
    equals = tibble::tibble(
      x = c(1L, 4L)
    ))

  test_vroom(I("1,2,3\n4,5,6"), col_names = "y", col_types = "_i_",
    equals = tibble::tibble(
      y = c(2L, 5L)
    ))

  test_vroom(I("1,2,3\n4,5,6"), col_names = "z", col_types = "__i",
    equals = tibble::tibble(
      z = c(3L, 6L)
    ))

  test_vroom(I("1,2,3\n4,5,6"), col_names = c("x", "z"), col_types = "i_i",
    equals = tibble::tibble(
      x = c(1L, 4L),
      z = c(3L, 6L)
    ))
})

test_that("unnamed column types can be less than the number of columns", {
  test_vroom("x,y\n1,2\n", col_types = "i",
    equals = tibble::tibble(
      x = 1L,
      y = 2L
    ))
})

test_that("always include the last row when guessing (#352)", {

  f <- tempfile()
  on.exit(unlink(f))

  vroom_write(data.frame("x" = c(rep(NA, 10), 5)), delim = ",", file = f)

  x <- vroom(f, col_types = "?", guess_max = 5, delim = ",")

  expect_type(x[[1]], "double")
})

test_that("vroom works with quote even in the first two lines (#1262)", {

  text <-
c("1,'I
am
sam'
2,'sam
I
am'")

  test_vroom(text, col_names = FALSE, quote = "'", delim = ",",
    equals = tibble::tibble(X1 = c(1, 2), X2 = c("I\nam\nsam", "sam\nI\nam")))
})

test_that("vroom works when grouping_mark is empty (#1241)", {
  x <- vroom(I("foo\nbar"), locale = locale(grouping_mark = ""), delim = ",", col_names = FALSE, col_types = "c")
  expect_equal(x[[1]], c("foo", "bar"))
})

test_that("vroom works if given col_names and col_types less than the number of columns (https://github.com/tidyverse/readr/issues/1271)", {
  x <- vroom(
    I("a\tb\n"),
    delim = "\t",
    col_names = c("x"),
    col_types = list("x" = "c")
  )

  expect_equal(x[["x"]], "a")
  expect_equal(x[["X2"]], "b")
})

test_that("vroom works with CR line endings only", {
  test_vroom(I("a,b\r1,2\r3,4\r"), delim = ",",
    equals = tibble::tibble(a = c(1, 3), b = c(2, 4))
  )
})

test_that("vroom works with quotes in comments", {
  test_vroom(I("a,b\n#bar \" xyz\n1,2"), delim = ",", comment = "#",
    equals = tibble::tibble(a = 1, b = 2)
  )

  test_vroom(I("#foo \" \na,b\n#bar \" xyz\n1,2"), delim = ",", comment = "#",
    equals = tibble::tibble(a = 1, b = 2)
  )
})

test_that("vroom works with comments at end of lines (https://github.com/tidyverse/readr/issues/1309)", {
  test_vroom(I("foo,bar#\n1,#\n2#\n#\n3\n"), delim = ",", comment = "#",
    equals = tibble::tibble(foo = c(1,2,3), bar = c(NA, NA, NA))
  )
})

test_that("vroom does not erronously warn for problems when there are embedded newlines and parsing needs to be restarted (https://github.com/tidyverse/readr/issues/1313))", {

  withr::local_seed(1)

  sample_values <- function(n, p_safe) {
    sample(c("safe", "UNSAFE\n"), n, replace = TRUE, prob = c(p_safe, 1 - p_safe))
  }

  n <- 300

  df <- tibble::tibble(
    a = sample_values(n, p_safe = .99),
    b = sample_values(n, p_safe = .01),
    c = sample_values(n, p_safe = .01)
  )

  # write to temp file
  path <- tempfile(pattern = "quoted_newlines_", fileext = ".csv")
  withr::defer(unlink(path))

  vroom_write(df, path, delim = ",")

  x <- vroom(path, delim = ",", col_types = list())
  y <- utils::read.csv(path, stringsAsFactors = FALSE)

  expect_warning(expect_equal(as.data.frame(x), y), NA)
})

test_that("n_max works with files without a trailing newline for file connections (https://github.com/tidyverse/readr/issues/1321)", {

  f <- tempfile()
  on.exit(unlink(f))

writeBin(charToRaw("foo,bar
1,2
3,4
5,6"), f)

  x <- vroom(f, n_max = Inf, delim = ",", col_types = list())
  y <- vroom(f, n_max = 4, delim = ",", col_types = list())
  z <- vroom(f, n_max = 5, delim = ",", col_types = list())
  expect_equal(y, x)
  expect_equal(z, x)
})

# https://github.com/tidyverse/vroom/issues/453
test_that("vroom can read a date column with no data and skip 1", {
  test_vroom("date\n", delim = ",", col_names = 'date', col_types = 'D', skip = 1,
             equals = tibble::tibble(date = as.Date(character()))
  )
})

# https://github.com/tidyverse/vroom/issues/453
test_that("vroom can read a datetime column with no data and skip 1", {
  test_vroom("dt\n", delim = ",", col_names = 'dt', col_types = 'T', skip = 1,
             equals = tibble::tibble(dt = as.POSIXct(character()))
  )
})