Add group_vars.grouped_epi_archive

Author: brookslogan

NAMESPACE

@@ -27,6 +27,7 @@ S3method(group_by,epi_df)
 S3method(group_by,grouped_epi_archive)
 S3method(group_by_drop_default,grouped_epi_archive)
 S3method(group_modify,epi_df)
+S3method(group_vars,grouped_epi_archive)
 S3method(groups,grouped_epi_archive)
 S3method(guess_period,Date)
 S3method(guess_period,POSIXt)

R/archive.R

@@ -585,8 +585,8 @@ print.epi_archive <- function(x, ..., class = TRUE, methods = TRUE) {
 #'   `...`.
 #' @param .drop As described in [`dplyr::group_by`]; determines treatment of
 #'   factor columns.
-#' @param x For `groups` or `ungroup`: a `grouped_epi_archive`; for
-#'   `is_grouped_epi_archive`: any object
+#' @param x For `groups`, `group_vars`, or `ungroup`: a `grouped_epi_archive`;
+#'   for `is_grouped_epi_archive`: any object
 #' @param .tbl (For `group_by_drop_default`:) an `epi_archive` or
 #'   `grouped_epi_archive` (`epi_archive` dispatches to the S3 default method;
 #'   `grouped_epi_archive` dispatches its own S3 method)
@@ -665,6 +665,11 @@ print.epi_archive <- function(x, ..., class = TRUE, methods = TRUE) {
 #'   group_by(geo_value, age_group) %>%
 #'   ungroup(age_group)
 #'
+#' # To get the grouping variable names as a character vector:
+#' toy_archive %>%
+#'   group_by(geo_value) %>%
+#'   group_vars()
+#'
 #' # To get the grouping variable names as a `list` of `name`s (a.k.a. symbols):
 #' toy_archive %>%
 #'   group_by(geo_value) %>%

R/grouped_epi_archive.R

@@ -55,7 +55,7 @@ new_grouped_epi_archive <- function(x, vars, drop) {
         or `ungroup` first.",
       class = "epiprocess__grouped_epi_archive__ungrouped_arg_is_already_grouped",
       epiprocess__ungrouped_class = class(x),
-      epiprocess__ungrouped_groups = groups(x)
+      epiprocess__ungrouped_group_vars = group_vars(x)
     )
   }
   assert_class(x, "epi_archive")
@@ -160,6 +160,14 @@ group_by_drop_default.grouped_epi_archive <- function(.tbl) {
   .tbl$private$drop
 }
 
+#' @include methods-epi_archive.R
+#' @rdname group_by.epi_archive
+#'
+#' @importFrom dplyr group_vars
+#' @export
+group_vars.grouped_epi_archive <- function(x) {
+  x$private$vars
+}
 
 #' @include methods-epi_archive.R
 #' @rdname group_by.epi_archive
@@ -170,7 +178,6 @@ groups.grouped_epi_archive <- function(x) {
   rlang::syms(x$private$vars)
 }
 
-
 #' @include methods-epi_archive.R
 #' @rdname group_by.epi_archive
 #'

man/group_by.epi_archive.Rd

@@ -110,7 +110,6 @@ test_that("epix_truncate_version_after returns the same grouping type as input e
   expect_true(is_grouped_epi_archive(ea_as_of))
 })
 
-
 test_that("epix_truncate_version_after returns the same groups as input grouped_epi_archive", {
   ea2 <- ea2_data %>%
     as_epi_archive()
@@ -122,3 +121,8 @@ test_that("epix_truncate_version_after returns the same groups as input grouped_
     epix_truncate_versions_after(max_version = as.Date("2020-06-04"))
   expect_equal(ea_as_of %>% groups(), ea_expected %>% groups())
 })
+
+test_that("group_vars works as expected", {
+  expect_equal(ea2_data %>% as_epi_archive() %>% group_by(geo_value) %>% group_vars(),
+               "geo_value")
+})