allow variant error messages

Author: teunbrand

tests/testthat/_snaps/4.0/theme.md

@@ -0,0 +1,8 @@
+# modifying theme element properties with + operator works
+
+    Code
+      theme_grey() + "asdf"
+    Condition
+      Error in `method(+, list(ggplot2::theme, class_any))`:
+      ! Can't add `"asdf"` to a theme object.
+

tests/testthat/_snaps/4.4/theme.md

@@ -0,0 +1,8 @@
+# modifying theme element properties with + operator works
+
+    Code
+      theme_grey() + "asdf"
+    Condition
+      Error:
+      ! Can't add `"asdf"` to a theme object.
+

tests/testthat/_snaps/error.md

@@ -1,19 +1,3 @@
-# modifying theme element properties with + operator works
-
-    Code
-      theme_grey() + "asdf"
-    Condition
-      Error:
-      ! Can't add `"asdf"` to a theme object.
-
-# replacing theme elements with %+replace% operator works
-
-    Code
-      theme_grey() + "asdf"
-    Condition
-      Error:
-      ! Can't add `"asdf"` to a theme object.
-
 # theme validation happens at build stage
 
     The `text` theme element must be a <element_text> object.

tests/testthat/_snaps/theme.md

@@ -5,6 +5,7 @@ test_that("ggplot() throws informative errors", {
 })
 
 test_that("construction have user friendly errors", {
+  skip_if(getRversion() < "4.3.0")
   expect_snapshot_error(+ geom_point())
   expect_snapshot_error(geom_point() + geom_bar())
   expect_snapshot_error(ggplot() + 1)

tests/testthat/test-error.R

@@ -49,7 +49,11 @@ test_that("modifying theme element properties with + operator works", {
   t <- theme_grey() + theme()
   expect_identical(t, theme_grey())
 
-  expect_snapshot(theme_grey() + "asdf", error = TRUE)
+  expect_snapshot(
+    theme_grey() + "asdf",
+    error = TRUE,
+    variant = substr(as.character(getRversion()), start = 1, stop = 3)
+  )
 })
 
 test_that("adding theme object to ggplot object with + operator works", {
@@ -114,8 +118,6 @@ test_that("replacing theme elements with %+replace% operator works", {
   # Adding empty theme() has no effect
   t <- theme_grey() %+replace% theme()
   expect_identical(t, theme_grey())
-
-  expect_snapshot(theme_grey() + "asdf", error = TRUE)
 })
 
 test_that("calculating theme element inheritance works", {