Check if an argument is a vector of type character

To check for scalar strings, see checkString.

checkCharacter(
  x,
  n.chars = NULL,
  min.chars = NULL,
  max.chars = NULL,
  pattern = NULL,
  fixed = NULL,
  ignore.case = FALSE,
  any.missing = TRUE,
  all.missing = TRUE,
  len = NULL,
  min.len = NULL,
  max.len = NULL,
  unique = FALSE,
  sorted = FALSE,
  names = NULL,
  typed.missing = FALSE,
  null.ok = FALSE
)

check_character(
  x,
  n.chars = NULL,
  min.chars = NULL,
  max.chars = NULL,
  pattern = NULL,
  fixed = NULL,
  ignore.case = FALSE,
  any.missing = TRUE,
  all.missing = TRUE,
  len = NULL,
  min.len = NULL,
  max.len = NULL,
  unique = FALSE,
  sorted = FALSE,
  names = NULL,
  typed.missing = FALSE,
  null.ok = FALSE
)

assertCharacter(
  x,
  n.chars = NULL,
  min.chars = NULL,
  max.chars = NULL,
  pattern = NULL,
  fixed = NULL,
  ignore.case = FALSE,
  any.missing = TRUE,
  all.missing = TRUE,
  len = NULL,
  min.len = NULL,
  max.len = NULL,
  unique = FALSE,
  sorted = FALSE,
  names = NULL,
  typed.missing = FALSE,
  null.ok = FALSE,
  .var.name = vname(x),
  add = NULL
)

assert_character(
  x,
  n.chars = NULL,
  min.chars = NULL,
  max.chars = NULL,
  pattern = NULL,
  fixed = NULL,
  ignore.case = FALSE,
  any.missing = TRUE,
  all.missing = TRUE,
  len = NULL,
  min.len = NULL,
  max.len = NULL,
  unique = FALSE,
  sorted = FALSE,
  names = NULL,
  typed.missing = FALSE,
  null.ok = FALSE,
  .var.name = vname(x),
  add = NULL
)

testCharacter(
  x,
  n.chars = NULL,
  min.chars = NULL,
  max.chars = NULL,
  pattern = NULL,
  fixed = NULL,
  ignore.case = FALSE,
  any.missing = TRUE,
  all.missing = TRUE,
  len = NULL,
  min.len = NULL,
  max.len = NULL,
  unique = FALSE,
  sorted = FALSE,
  names = NULL,
  typed.missing = FALSE,
  null.ok = FALSE
)

test_character(
  x,
  n.chars = NULL,
  min.chars = NULL,
  max.chars = NULL,
  pattern = NULL,
  fixed = NULL,
  ignore.case = FALSE,
  any.missing = TRUE,
  all.missing = TRUE,
  len = NULL,
  min.len = NULL,
  max.len = NULL,
  unique = FALSE,
  sorted = FALSE,
  names = NULL,
  typed.missing = FALSE,
  null.ok = FALSE
)

expect_character(
  x,
  n.chars = NULL,
  min.chars = NULL,
  max.chars = NULL,
  pattern = NULL,
  fixed = NULL,
  ignore.case = FALSE,
  any.missing = TRUE,
  all.missing = TRUE,
  len = NULL,
  min.len = NULL,
  max.len = NULL,
  unique = FALSE,
  sorted = FALSE,
  names = NULL,
  typed.missing = FALSE,
  null.ok = FALSE,
  info = NULL,
  label = vname(x)
)

Arguments

x

[any]
Object to check.

n.chars

[integer(1)]
Exact number of characters for each element of x.

min.chars

[integer(1)]
Minimum number of characters for each element of x.

max.chars

[integer(1)]
Maximum number of characters for each element of x.

pattern

[character(1L)]
Regular expression as used in grepl. All non-missing elements of x must comply to this pattern.

fixed

[character(1)]
Substring to detect in x. Will be used as pattern in grepl with option fixed set to TRUE. All non-missing elements of x must contain this substring.

ignore.case

[logical(1)]
See grepl. Default is FALSE.

any.missing

[logical(1)]
Are vectors with missing values allowed? Default is TRUE.

all.missing

[logical(1)]
Are vectors with no non-missing values allowed? Default is TRUE. Note that empty vectors do not have non-missing values.

len

[integer(1)]
Exact expected length of x.

min.len

[integer(1)]
Minimal length of x.

max.len

[integer(1)]
Maximal length of x.

unique

[logical(1)]
Must all values be unique? Default is FALSE.

sorted

[logical(1)]
Elements must be sorted in ascending order. Missing values are ignored.

names

[character(1)]
Check for names. See checkNamed for possible values. Default is “any” which performs no check at all. Note that you can use checkSubset to check for a specific set of names.

typed.missing

[logical(1)]
If set to FALSE (default), all types of missing values (NA, NA_integer_, NA_real_, NA_character_ or NA_character_) as well as empty vectors are allowed while type-checking atomic input. Set to TRUE to enable strict type checking.

null.ok

[logical(1)]
If set to TRUE, x may also be NULL. In this case only a type check of x is performed, all additional checks are disabled.

.var.name

[character(1)]
Name of the checked object to print in assertions. Defaults to the heuristic implemented in vname.

add

[AssertCollection]
Collection to store assertion messages. See AssertCollection.

info

[character(1)]
Extra information to be included in the message for the testthat reporter. See expect_that.

label

[character(1)]
Name of the checked object to print in messages. Defaults to the heuristic implemented in vname.

Value

Depending on the function prefix: If the check is successful, the functions

assertCharacter/assert_character return

x invisibly, whereas

checkCharacter/check_character and

testCharacter/test_character return

TRUE. If the check is not successful,

assertCharacter/assert_character

throws an error message,

testCharacter/test_character

returns FALSE, and checkCharacter/check_character

return a string with the error message. The function expect_character always returns an

expectation.

Details

This function does not distinguish between NA, NA_integer_, NA_real_, NA_complex_ NA_character_ and NaN.

See also

Other basetypes: checkArray(), checkAtomicVector(), checkAtomic(), checkComplex(), checkDataFrame(), checkDate(), checkDouble(), checkEnvironment(), checkFactor(), checkFormula(), checkFunction(), checkIntegerish(), checkInteger(), checkList(), checkLogical(), checkMatrix(), checkNull(), checkNumeric(), checkPOSIXct(), checkRaw(), checkVector()

Examples

testCharacter(letters, min.len = 1, any.missing = FALSE)
#> [1] TRUE
testCharacter(letters, min.chars = 2)
#> [1] FALSE
testCharacter("example", pattern = "xa")
#> [1] TRUE