diff --git a/test/test_unit_report_invalid_alts.py b/test/test_unit_report_invalid_alts.py
new file mode 100644
index 0000000..7aa93bb
--- /dev/null
+++ b/test/test_unit_report_invalid_alts.py
@@ -0,0 +1,39 @@
+"""Unit tests: report_invalid_alts"""
+import pytest
+
+
+@pytest.mark.parametrize(
+    'condition', [
+        'compat',
+        'previous-message',
+        'invalid-alts',
+        'no-invalid-alts',
+    ])
+def test_report_invalid_alts(runner, yadm, condition):
+    """Use report_invalid_alts"""
+
+    compat = ''
+    previous = ''
+    alts = 'INVALID_ALT=()'
+    if condition == 'compat':
+        compat = 'YADM_COMPATIBILITY=1'
+    if condition == 'previous-message':
+        previous = 'LEGACY_WARNING_ISSUED=1'
+    if condition == 'invalid-alts':
+        alts = 'INVALID_ALT=("file##invalid")'
+
+    script = f"""
+        YADM_TEST=1 source {yadm}
+        {compat}
+        {previous}
+        {alts}
+        report_invalid_alts
+    """
+    run = runner(command=['bash'], inp=script)
+    assert run.success
+    assert run.err == ''
+    if condition == 'invalid-alts':
+        assert 'WARNING' in run.out
+        assert 'file##invalid' in run.out
+    else:
+        assert run.out == ''
diff --git a/test/test_unit_score_file.py b/test/test_unit_score_file.py
index 5719fe4..679229f 100644
--- a/test/test_unit_score_file.py
+++ b/test/test_unit_score_file.py
@@ -260,3 +260,19 @@ def test_template_recording(runner, yadm, cmd_generated):
     assert run.success
     assert run.err == ''
     assert run.out.rstrip() == expected
+
+
+def test_invalid(runner, yadm):
+    """Verify invalid alternates are noted in INVALID_ALT"""
+
+    invalid_file = "file##invalid"
+
+    script = f"""
+        YADM_TEST=1 source {yadm}
+        score_file "{invalid_file}"
+        echo "INVALID:${{INVALID_ALT[@]}}"
+    """
+    run = runner(command=['bash'], inp=script)
+    assert run.success
+    assert run.err == ''
+    assert run.out.rstrip() == f'INVALID:{invalid_file}'