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Validation - Expression vectors

test_expression.Rd

Test if an object is an expression vector or expression object.

test_expression() is the predicate test, while assert_expression() validates its input, aborting if it fails the test.

Usage

test_expression(
  x,
  len = NULL,
  n_null = NULL,
  n_call = NULL,
  n_sym = NULL,
  n_literal = NULL,
  n_invalid = NULL,
  sentinels = NULL,
  custom = NULL,
  custom_map = NULL
)

assert_expression(
  x,
  len = NULL,
  n_null = NULL,
  n_call = NULL,
  n_sym = NULL,
  n_literal = NULL,
  n_invalid = NULL,
  sentinels = NULL,
  custom = NULL,
  custom_map = NULL,
  action = "abort",
  env = caller_env(),
  x_name = NULL,
  short_circuit = TRUE,
  report_untested = TRUE,
  args_cnd = list()
)

Arguments

x

[any] An object to test.

len, n_null, n_call, n_sym, n_literal, n_invalid

[numeric() | \(){} | NULL] Possible values for the length, number of NULL elements, number of 'language' elements, number of 'symbol' elements, number of syntactic literal elements, number of non-syntactic elements. The options of each argument 'arg' are:

  • NULL to not test.

  • A single non-negative number to test for . == arg. If Inf, . == length(x).

  • A single negative number to test for . == length(x) + arg.

  • A vector of two non-negative numbers to test for arg[1] <= . <= arg[2] (Inf is allowed).

  • A vector of three or more non-negative numbers to test for . %in% arg.

  • A function that receives the value to test and the length of x, and returns a single TRUE or FALSE.

sentinels

[character() | NULL] Each entry in this character vector allows x to also be some scalar sentinel below. Set to NULL to disconsider sentinels.

  • "null" for NULL.

  • "empty" for any zero-length object.

  • "na" for any NA type, or "na_logical" for NA, "na_integer" for NA_integer_, "na_real" for NA_real_, "na_complex" for NA_complex_, and "na_character" for NA_character_.

  • "nan" for NaN.

  • "+inf" for +Inf, "-inf" for -Inf, and "inf" for both.

  • "true"/"t" for TRUE, and "false"/"f" for FALSE.

custom

[function(x) | NULL] A custom function that takes x as first argument and returns a single TRUE or FALSE. Set to NULL to not test.

custom_map

[function(x) | NULL] A custom function that is applied to each element of x. Must return a single TRUE or FALSE for each element. Set to NULL to not test.

action

["abort" | "warn" | "inform"] Action to take when the test fails:

  • "abort" to stop execution and throw an error.

  • "warning" to issue a warning and return invisible(x).

  • "message" to issue a message and return invisible(x).

env

[environment() | call() | NULL | missing_arg()] The call to inform as the origin of the error, passed to rlang::abort():

  • An environment in the call stack or a hard-coded defused call.

  • NULL for no information.

  • missing_arg() to use the assert function itself.

  • The default is caller_env(), to display the function where the assertion was called.

x_name

[character(1) | NULL] The name of the object to use in the error message. If NULL, the name is inferred from the expression passed to x.

short_circuit

[TRUE | FALSE] If TRUE, the tests results will be reported up to the first failure. Else, all tests results are reported. The former is more efficient, while the latter is more informative.

report_untested

[TRUE | FALSE] If TRUE, the tests that were not run due to short- circuiting will be reported as untested, else, ignored.

args_cnd

[list()] Additional arguments passed to cli::cli_abort(), cli::cli_warn(), or cli::cli_inform(), based on the chosen action.

Value

  • [TRUE | FALSE] for test_expression().

  • [=x] invisible(x) for assert_expression(), or aborts if the test fails.