From 014f09907bfc1c9b2fa1837c647845d55f5daf0d Mon Sep 17 00:00:00 2001
From: AdamK-A <103337795+AdamK-A@users.noreply.github.com>
Date: Tue, 10 Dec 2024 12:27:27 -0800
Subject: [PATCH] Fixed factor cross ordering

---
 DESCRIPTION                 |  2 +-
 R/cross.R                   |  3 ++-
 tests/testthat/test-cross.R | 20 ++++++++++++++++++++
 3 files changed, 23 insertions(+), 2 deletions(-)

diff --git a/DESCRIPTION b/DESCRIPTION
index ce124d87..2a131a62 100644
--- a/DESCRIPTION
+++ b/DESCRIPTION
@@ -38,4 +38,4 @@ Config/testthat/edition: 3
 Encoding: UTF-8
 LazyData: true
 Roxygen: list(markdown = TRUE)
-RoxygenNote: 7.2.3
+RoxygenNote: 7.3.2
diff --git a/R/cross.R b/R/cross.R
index 6901aa10..f37761a8 100644
--- a/R/cross.R
+++ b/R/cross.R
@@ -32,7 +32,8 @@ fct_cross <- function(..., sep = ":", keep_empty = FALSE) {
   newf <- exec(paste, !!!.data, sep = sep)
 
   old_levels <- lapply(.data, levels)
-  grid <- exec(expand.grid, old_levels)
+  grid_unsorted <- exec(expand.grid, old_levels)
+  grid <- grid_unsorted[do.call(order, grid_unsorted), ]
   new_levels <- exec(paste, !!!grid, sep = sep)
 
   if (!keep_empty) {
diff --git a/tests/testthat/test-cross.R b/tests/testthat/test-cross.R
index 3f6d827e..2d354fe3 100644
--- a/tests/testthat/test-cross.R
+++ b/tests/testthat/test-cross.R
@@ -71,3 +71,23 @@ test_that("validates its inputs", {
     fct_cross("x", keep_empty = 1)
   })
 })
+
+test_that("Cross factoring 2 levels in order", {
+  f1 <- fct_inorder(c("a4", "a3", "a2", "a1"))
+  f2 <- factor(c("b4", "b3", "b2", "b1"))
+
+  fcross <- fct_cross(f1, f2)
+
+  expect_equal(levels(fcross), c("a4:b4", "a3:b3", "a2:b2", "a1:b1"))
+})
+
+
+test_that("Cross factoring 3 levels in order by first level", {
+  f1 <- fct_inorder(c("a4", "a3", "a2", "a1"))
+  f2 <- factor(c("b4", "b3", "b2", "b1"))
+  f3 <- factor(c("c4", "c3", "c2", "c1"))
+
+  fcross <- fct_cross(f1, f2, f3)
+
+  expect_equal(levels(fcross), c("a4:b4:c4", "a3:b3:c3", "a2:b2:c2", "a1:b1:c1"))
+})