diff --git a/equinox/internal/_loop/checkpointed.py b/equinox/internal/_loop/checkpointed.py
index 51e3c4ef..d3a54455 100644
--- a/equinox/internal/_loop/checkpointed.py
+++ b/equinox/internal/_loop/checkpointed.py
@@ -311,7 +311,8 @@ def _stumm_walther_i(step, save_state):
         "`equinox.internal.checkpointed_while_loop`. "
         "Please raise an issue at https://github.com/patrick-kidger/equinox"
     )
-    out = error_if(out, pred & (o == -1), msg)
+    if getattr(typing, "TESTING", False):
+        out = error_if(out, pred & (o == -1), msg)
     out = nonbatchable(out)
     return out
 
@@ -800,7 +801,8 @@ def _body_fun(carry):
             "`equinox.internal.checkpointed_while_loop`. "
             "Please raise an issue at https://github.com/patrick-kidger/equinox"
         )
-        step_val = error_if(step_val, step_val >= step_grad_val, msg)
+        if getattr(typing, "TESTING", False):
+            step_val = error_if(step_val, step_val >= step_grad_val, msg)
 
         #
         # First either propagate our primal state forward, or make a U-turn if the