Check if "weights" exists for vector-method (#485)

* Check if "weights" exists for vector-method

* wording

* fix check

* comment

* comment

* styler

* simplify nesting

* refactor

* comment to structure

* styler

DESCRIPTION

@@ -1,7 +1,7 @@
 Type: Package
 Package: datawizard
 Title: Easy Data Wrangling and Statistical Transformations
-Version: 0.9.1.5
+Version: 0.9.1.6
 Authors@R: c(
     person("Indrajeet", "Patil", , "[email protected]", role = "aut",
            comment = c(ORCID = "0000-0003-1995-6531", Twitter = "@patilindrajeets")),

R/data_tabulate.R

@@ -141,7 +141,7 @@ data_tabulate.default <- function(x,
   }
 
   # validate "weights"
-  weights <- .validate_table_weights(weights, x)
+  weights <- .validate_table_weights(weights, x, weights_expression = insight::safe_deparse(substitute(weights)))
 
   # we go into another function for crosstables here...
   if (!is.null(by)) {

R/data_xtabulate.R

@@ -312,8 +312,39 @@ print_html.dw_data_xtabulates <- function(x, big_mark = NULL, ...) {
 }
 
 
-.validate_table_weights <- function(weights, x) {
-  if (!is.null(weights)) {
+.validate_table_weights <- function(weights, x, weights_expression = NULL) {
+  # exception: for vectors, if weighting variable not found, "weights" is NULL.
+  # to check this, we further need to check whether a weights expression was
+  # provided, e.g. "weights = iris$not_found" - all this is only relevant when
+  # weights is NULL
+  if (is.null(weights)) {
+    # possibly misspelled weights-variables for default-method ----------------
+    # -------------------------------------------------------------------------
+
+    # do we have any value for weights_expression?
+    if (!is.null(weights_expression) &&
+      # due to deparse() and substitute, NULL becomes "NULL" - we need to check for this
+      !identical(weights_expression, "NULL") &&
+      # we should only run into this problem, when a variable from a data frame
+      # is used in the data_tabulate() method for vectors - thus, we need to check
+      # whether the weights_expression contains a "$" - `iris$not_found` is "NULL"
+      # we need this check, because the default-method of data_tabulate() is called
+      # from the data.frame method, where `weights = weights`, and then,
+      # deparse(substitute(weights)) is "weights" (not "NULL" or "iris$not_found"),
+      # leading to an error when actually all is OK (if "weights" is NULL)
+      # Example:
+      #> efc$weights <- abs(rnorm(n = nrow(efc), mean = 1, sd = 0.5))
+      # Here, efc$wweight is NULL
+      #> data_tabulate(efc$c172code, weights = efc$wweight)
+      # Here, wweight errors anyway, because object "wweight" is not found
+      #> data_tabulate(efc$c172code, weights = wweight)
+      grepl("$", weights_expression, fixed = TRUE)) {
+      insight::format_error("The variable specified in `weights` was not found. Possibly misspelled?")
+    }
+  } else {
+    # possibly misspecified weights-variables for data.frame-method -----------
+    # -------------------------------------------------------------------------
+
     if (is.character(weights)) {
       # If "weights" is a character string, must be of length 1
       if (length(weights) > 1) {

tests/testthat/test-data_tabulate.R

@@ -363,6 +363,7 @@ test_that("data_tabulate, cross tables, errors weights", {
   expect_error(data_tabulate(efc, "c172code", weights = efc$weights[-1]), regex = "Length of `weights`")
   expect_error(data_tabulate(efc, "c172code", weights = "weigths"), regex = "not found")
   expect_error(data_tabulate(efc, "c172code", weights = c("e16sex", "e42dep")), regex = "length 1")
+  expect_error(data_tabulate(efc$c172code, weights = efc$wweight), regex = "not found")
 })