Builtin Validation Rules • RV

library(RV)

RV has 30 validation rules and 10 cross rules.

Validation rules

Registry()@rule_names
#>  [1] "required"       "default"        "coerce"         "apply"         
#>  [5] "type"           "inherits"       "allowed"        "forbidden"     
#>  [9] "unique"         "positive"       "negative"       "finite"        
#> [13] "allow_na"       "min_val"        "max_val"        "min_length"    
#> [17] "max_length"     "min_nrow"       "max_nrow"       "min_nchar"     
#> [21] "max_nchar"      "nzchar"         "regex"          "labelled"      
#> [25] "levels"         "ordered_levels" "dependency"     "dependencies"  
#> [29] "predicate"      "apply_last"

The builtin rules are categorised by their type: ‘control’, ‘transform’ and ‘validate’. When the Validator is run, rules are applied in three passes according to these categories, with a special final pass for the ‘apply_last’ rule.

Rules within each category are applied in the order they appear in their respective Registry property.

r <- Registry()
r@control_rules
#> [1] "required" "default"
r@transform_rules
#> [1] "coerce" "apply"
r@validate_rules
#>  [1] "type"           "inherits"       "allowed"        "forbidden"     
#>  [5] "unique"         "positive"       "negative"       "finite"        
#>  [9] "allow_na"       "min_val"        "max_val"        "min_length"    
#> [13] "max_length"     "min_nrow"       "max_nrow"       "min_nchar"     
#> [17] "max_nchar"      "nzchar"         "regex"          "labelled"      
#> [21] "levels"         "ordered_levels" "dependency"     "dependencies"  
#> [25] "predicate"

Each validation rule has two functions associated with it:

A function that validates the given schema value.

Schema(list(type = 1L), error = TRUE)
#> Error:
#> ! <RV::Schema> object is invalid:
#> - Schema validation failed with the following errors:
#> └─ type: Must be a function or a string.

A function that uses the schema value to validate data.

Validator(
  data = 1L,
  schema = list(type = "character"),
  error = TRUE
)
#> Error:
#> ! <RV::Validator> object is invalid:
#> - Data validation failed with the following errors:
#> └─ type: Is not type `character`.

Cross rules

Cross rules operate within the Schema, checking that the values of two or more schema rules don’t clash. They are not exhaustive, but apply to a number of common scenarios.

Schema(
  list(
    min_length = 5,
    max_length = 1
  ),
  error = TRUE
)
#> Error:
#> ! <RV::Schema> object is invalid:
#> - Schema validation failed with the following errors:
#> ├─ min_length: `min_length` must be smaller than `max_length`.
#> └─ max_length: `min_length` must be smaller than `max_length`.

Rule information

Validation rules

Rule	Schema operation	Data operation	Control flow
	Checks schema value is:	Checks/transforms data element:	Stops other rules if:
`required`	boolean.	exists.	FALSE and element not present.
`default`	non-empty.	exists and inserts `default` if not.	default is used.
`apply`	function or a valid string.	applies function.
`coerce`	1 arg function or a valid string.	coerces.
`type`	1 arg function or a valid string.	type.
`inherits`	character vector.	inherits from specified classes.
`allowed`	non-empty vector.	only values in `allowed` set.
`forbidden`	non-empty vector.	no values in `forbidden` set.
`unique`	TRUE.	no duplicates.
`positive`	TRUE.	is positive (or zero).
`negative`	TRUE.	is negative (or zero).
`finite`	TRUE.	is finite.
`allow_na`	TRUE.	no `NA` values.
`min_val`	finite numeric value.	values at least `min_val`.
`max_val`	finite numeric value.	values at most `max_val`.
`min_length`	positive integerish value.	length at least `min_length`.
`max_length`	positive integerish value.	length at most `max_length`.
`min_nrow`	positive integerish value.	nrow at least `min_nrow`.
`max_nrow`	positive integerish value.	nrow at most `max_nrow`.
`min_nchar`	positive integerish value.	nchar at least `min_nchar`.
`max_nchar`	positive integerish value.	nchar at most `max_nchar`.
`nzchar`	boolean.	no empty strings.
`regex`	string.	matches `regex` pattern.
`labelled`	boolean.	is labelled (has `labels` attribute).
`levels`	character vector.	has levels matching `levels` in any order.
`ordered_levels`	character vector.	has levels matching `ordered_levels` in order.
`dependency`	character vector, or integerish vector, or list of string/integerish scalars.	dependency field present.
`dependencies`	list of character vectors, or integerish vectors, or lists of string/integerish scalars.	dependency fields present.
`predicate`	function or a valid string.	satisfies predicate function.
`apply_last`	function or a valid string.	applies function in no errors in node.

Cross rules

Cross rule	Schema operation
	Checks in a schema node that:
`dependency_and_dependencies`	`dependency` and `dependencies` rules aren’t both present.
`required_and_default`	if `required` is TRUE that a `default` value is not provided.
`positive_and_negative`	`positive` and `negative` rules aren’t both present.
`min_val_larger_than_max_val`	`min_val` is smaller than `max_val`.
`min_length_larger_than_max_length`	`min_length` is smaller than `max_length`.
`min_nrow_larger_than_max_nrow`	`min_nrow` is smaller than `max_nrow`.
`min_nchar_larger_than_max_nchar`	`min_nchar` is smaller than `max_nchar`.
`allowed_and_forbidden_overlap`	values in `allowed` and `forbidden` do not overlap.
`allowed_type_mismatch`	values in `allowed` are of the type specified in `type`.
`forbidden_type_mismatch`	values in `forbidden` are of the type specified in `type`.

Note

To quickly see the builtin rules at the terminal, use show_RV_builtins().