diff --git a/tests/test_run.py b/tests/test_run.py
index 47d3a6a535aa8a962ab97993f2586cd76be28413..be9e443ca5d6b6da98b3bbf6187eff339d5c11b8 100644
--- a/tests/test_run.py
+++ b/tests/test_run.py
@@ -233,6 +233,10 @@ def test_runfsl():
             fslplatform.fsldir = fsldir
             assert run.runfsl('fslhd').strip() == 'fsldir'
 
+            # non-FSL command - should error
+            with pytest.raises(FileNotFoundError):
+                run.runfsl('ls')
+
             # FSLDEVDIR should take precedence
             fsldevdir = './fsldev'
             fslhd  = op.join(fsldevdir, 'bin', 'fslhd')