Feature request: Add + for rulesets

DESCRIPTION

@@ -6,7 +6,12 @@ Authors@R: c(
       person(given = "David",
              family = "Zimmermann-Kollenda",
              role = c("aut","cre"),
-             email = "[email protected]"))
+             email = "[email protected]"),
+      person(given = "Beniamino",
+             family = "Green",
+             role = "ctb",
+             email = "[email protected]")
+      )
 Description: Allows you to define rules which can be used to verify a given
     dataset.
     The package acts as a thin wrapper around more powerful data packages such
@@ -15,9 +20,9 @@ License: MIT + file LICENSE
 URL: https://github.com/DavZim/dataverifyr,
     https://davzim.github.io/dataverifyr/
 BugReports: https://github.com/DavZim/dataverifyr/issues
-Imports: 
+Imports:
     yaml
-Suggests: 
+Suggests:
     arrow,
     data.table,
     DBI,

NAMESPACE

@@ -1,9 +1,9 @@
 # Generated by roxygen2: do not edit by hand
 
+S3method("+",rule)
 S3method("+",ruleset)
 S3method(print,rule)
 S3method(print,ruleset)
-export("%+%")
 export(check_data)
 export(detect_backend)
 export(filter_fails)

R/ruleset_construction.R

@@ -1,24 +1,54 @@
-#' Add Rulesets Together
+#' Add Rules and Rulesets Together
 #'
-#' `+` allows you to concatenate several rulesets into a larger rulesets. This
+#' `+` allows you to add rules and rulesets into larger rulesets. This
 #' can be useful if you want to create a ruleset for a dataset out of checks
 #' for other datasets.
 #'
 #' @param a the first ruleset you wish to add
 #' @param a the second ruleset you wish to add
 #' @rdname ruleset_add
-#' @export
-"+.ruleset" <- function(a,b) {
-	out <- c(a,b)
-	class(out) <- "ruleset"
+datavarifyr_plus  <- function(a,b) {
+    # This is the method to add *both* rules and rulesets together.
+    # Has to be done this way AFAIK to comply with R's
+    # [double dispatch](https://yutani.rbind.io/post/double-dispatch-of-s3-method/)
+    # semantics.
+
+    if (class(a) == "ruleset" & class(b)=="ruleset") {
+        out <- c(a,b)
+    } else if (class(a) == "ruleset" & class(b) == "rule"){
+        out <- c(a,list(b))
+    } else if (class(a) == "rule" & class(b) == "ruleset"){
+        out <- c(list(a),b)
+    } else{
+        out <- list(a,b)
+    }
 
     for (i in seq_along(out)){
         out[[i]]['index'] <- i
     }
 
-	out
+    class(out) <- "ruleset"
+    return(out)
 }
 
-#' @rdname ruleset_add
 #' @export
-"%+%" <- `+.ruleset`
+#' @rdname dataverifyr_add
+"+.ruleset" <- datavarifyr_plus
+
+#' @export
+#' @rdname dataverifyr_add
+"+.rule" <- datavarifyr_plus
+
+
+###############################################################################
+
+#' Programatically Combine a List of Rules and Rulesets into a Single Ruleset
+#'
+#' @param rule_ruleset_list a list of rules and rulesets you whish to combine
+#' into a single list
+#'
+#' @return a ruleset which consolidates all the inputs
+bind_rules <- function(rule_ruleset_list) {
+    Reduce(`+`, rule_ruleset_list)
+}
+

tests/testthat/test-ruleset_construction.R

@@ -0,0 +1,69 @@
+test_that("Rules can be added together", {
+  rule_1 <- rule(mpg >10)
+  rule_2 <- rule(hp >10)
+  expect_equal(
+               rule_1 + rule_2,
+               ruleset(rule_1, rule_2)
+               )
+
+})
+
+test_that("Rules can be added to rulesets", {
+  rule_1 <- rule(mpg >10)
+  rule_2 <- rule(hp >10)
+  rule_3 <- rule(name == "henry")
+
+  expect_equal(
+               rule_1 + ruleset(rule_2, rule_3),
+               ruleset(rule_1, rule_2, rule_3)
+               )
+
+})
+
+test_that("rulesets can be added to rules", {
+  rule_1 <- rule(mpg >10)
+  rule_2 <- rule(hp >10)
+  rule_3 <- rule(name == "henry")
+
+  expect_equal(
+               ruleset(rule_1, rule_2) + rule_3,
+               ruleset(rule_1, rule_2, rule_3)
+               )
+
+})
+
+test_that("rulesets can be added to rules", {
+  rule_1 <- rule(mpg >10)
+  rule_2 <- rule(hp >10)
+  rule_3 <- rule(name == "henry")
+  rule_4 <- rule(sex == "female")
+
+  expect_equal(
+               ruleset(rule_1, rule_2) + ruleset(rule_3, rule_4),
+               ruleset(rule_1, rule_2, rule_3, rule_4)
+               )
+
+})
+
+test_that("bind_rules works", {
+  rule_1 <- rule(mpg >10)
+  rule_2 <- rule(hp >10)
+  rule_3 <- rule(name == "henry")
+  rule_4 <- rule(sex == "female")
+
+  expect_equal(
+               bind_rules(list(rule_1, rule_2, ruleset(rule_3, rule_4))),
+               ruleset(rule_1, rule_2, rule_3, rule_4)
+               )
+
+  expect_equal(
+               bind_rules(list(ruleset(rule_1, rule_2), ruleset(rule_3, rule_4))),
+               ruleset(rule_1, rule_2, rule_3, rule_4)
+               )
+
+  expect_equal(
+               bind_rules(list(rule_1, ruleset(rule_2), ruleset(rule_3, rule_4))),
+               ruleset(rule_1, rule_2, rule_3, rule_4)
+               )
+
+})