From bc448a92e097a3dfc978a7d589c340a194a5e057 Mon Sep 17 00:00:00 2001
From: Lionel Henry <lionel.hry@proton.me>
Date: Mon, 28 Oct 2024 11:50:02 +0100
Subject: [PATCH] Set `LANGUAGE` to `"C"`

---
 NEWS.md   | 4 ++++
 R/local.R | 9 ++-------
 2 files changed, 6 insertions(+), 7 deletions(-)

diff --git a/NEWS.md b/NEWS.md
index 6eb90a984..164a3df9c 100644
--- a/NEWS.md
+++ b/NEWS.md
@@ -1,5 +1,9 @@
 # testthat (development version)
 
+* `LANGUAGE` is now set to `"C"` in reprocucible environments (i.e.
+  `test_that()` blocks) to disable translations. This fixes warnings
+  about being unable to set the language to `"en"` (#1925).
+
 # testthat 3.2.1
 
 * Fix incorrect format string detected by latest R-devel. Fix thanks to 
diff --git a/R/local.R b/R/local.R
index 2666822ae..b8693bab0 100644
--- a/R/local.R
+++ b/R/local.R
@@ -98,7 +98,7 @@ local_reproducible_output <- function(width = 80,
                                       unicode = FALSE,
                                       rstudio = FALSE,
                                       hyperlinks = FALSE,
-                                      lang = "en",
+                                      lang = "C",
                                       .env = parent.frame()) {
 
   if (unicode) {
@@ -133,12 +133,7 @@ local_reproducible_output <- function(width = 80,
     .local_envir = .env
   )
 
-  if (isTRUE(capabilities("NLS"))) {
-    suppressWarnings(
-      withr::local_language(lang, .local_envir = .env)
-    )
-  }
-
+  withr::local_language(lang, .local_envir = .env)
   withr::local_collate("C", .local_envir = .env)
 }