Test whether variables in a data frame are labelled in a given way.

expect_labels(
  vars,
  val_labels = NULL,
  var_label = NULL,
  flt = TRUE,
  data = get_testdata()
)

Arguments

vars

<tidy-select> A set of columns to test.

val_labels

What value label check should be performed? One of:

  • A character vector of expected value labels.

  • A named vector of expected label-value pairs.

  • TRUE to test for the presence of value labels in general.

  • FALSE to test for the absence of value labels.

  • NULL to ignore value labels when checking.

var_label

What variable label check should be performed? One of:

  • A character vector of expected variable labels.

  • TRUE to test for the presence of a variable labels.

  • FALSE to test for the absence of a variable labels.

  • NULL to ignore the variable label when checking.

flt

<data-masking> A filter specifying a subset of the data frame to test.

data

A data frame to test. The global test data is used by default.

Value

expect_*() functions are mainly called for their side effects. The expectation signals its result (e.g. "success", "failure"), which is logged by the current test reporter. In a non-testing context the expectation will raise an error with class expectation_failure if it fails.

Examples


df <- data.frame(
  x = labelled::labelled(c("M", "M", "F"), c(Male = "M", Female = "F"), "Sex"),
  y = labelled::labelled(c("M", "M", "F"), c(Male = "M", Female = "F", Other = "X")),
  z = c("M", "M", "F")
)

# Check for a value-label pairing
try(expect_labels(x, c(Male = "M"), data = df))
#> Error : `df` has 1 records failing label check on variable `x`.
#> Filter: None
#> Arguments: `val_labels = <chr: Male = "M">, var_label = NULL`

# Check that two variables have the same values
expect_labels(x, labelled::val_labels(df$y), data = df) # N.B. This passes!

# Check for the presence of a particular label
try(expect_labels(x, "Male", data = df))
#> Error : `df` has 1 records failing label check on variable `x`.
#> Filter: None
#> Arguments: `val_labels = "Male", var_label = NULL`
expect_labels(x, var_label = "Sex", data = df)

# Check that a variable is labelled at all
try(expect_labels(z, val_labels = TRUE, data = df))
#> Error : `df` has 3 records failing label check on variable `z`.
#> Filter: None
#> Arguments: `val_labels = TRUE, var_label = NULL`
try(expect_labels(z, var_label = TRUE, data = df))
#> Error : `df` has 3 records failing label check on variable `z`.
#> Filter: None
#> Arguments: `val_labels = NULL, var_label = TRUE`

# Check that a variable isn't labelled
expect_labels(z, val_labels = FALSE, data = df)
expect_labels(z, var_label = FALSE, data = df)