Validation - Symbol

Usage

test_symbol(
  x,
  n_char = NULL,
  valid = NULL,
  empty = NULL,
  env_has = NULL,
  env_seen = NULL,
  sentinels = NULL,
  custom = NULL
)

assert_symbol(
  x,
  n_char = NULL,
  valid = NULL,
  empty = NULL,
  env_has = NULL,
  env_seen = NULL,
  sentinels = NULL,
  custom = 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.

n_char

[numeric() | \(){} | NULL] Possible values for the number of characters (vectorized). 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.

valid

[TRUE | FALSE | NULL] Test if the symbol name is a valid syntactic R name (i.e. unchanged when processed by make.names()). Set to NULL to not test.

empty

[TRUE | FALSE | NULL] Test if the symbol is empty (i.e. ""). Set to NULL to not test.

env_has, env_seen

[environment | NULL] Environment in which the symbol exists directly, or inherited from one of its parents, respectively (see rlang::env_has()). Set to NULL to not test.

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.

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_symbol().

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

Examples

x <- quote(my_var)

args <- list(
  n_char = c(1, 10),      # Symbol string length must be between 1 and 10 (will pass)
  valid = TRUE,           # Must be a valid syntactic R name (will pass)
  empty = FALSE,          # Symbol must not be the empty symbol (will pass)
  env_has = rlang::global_env(),
  # Symbol must exist directly in global environment (will fail)
  env_seen = NULL,        # Don't test environment inheritance
  sentinels = c("null"),  # Allow NULL symbol (not the case of x)
  custom = NULL           # No custom test predicate
)

rlang::exec(test_symbol, !!!c(list(x), args)) #> FALSE (not all tests passed)
#> [1] FALSE

try(rlang::exec(assert_symbol, !!!c(list(x), args, short_circuit = FALSE))) #> Error
#> Error in eval(expr, envir) : 
#>   `.Primitive("quote")(my_var)` failed `assert_symbol()`:
#> ✔ (pass) sentinels: no sentinel values allowed.
#> ✔ (pass) type  : must be of type "symbol".
#> ✔ (pass) n_char: #of characters must be in range 1 to 10.
#> ✔ (pass) valid : must be a syntactically valid R name.
#> ✖ (fail) env_has: must contain "my_var". Is missing "my_var".
#> 
#> ℹ See `predicater::assert_symbol()` and this condition's `rs_assert_error`
#>   attribute for details.