Add test for spawn when exe is missing. Ref pypa/distutils#3.

distutils/tests/test_spawn.py

@@ -126,6 +126,11 @@ class SpawnTestCase(support.TempdirManager,
                     rv = find_executable(program)
                     self.assertEqual(rv, filename)
 
+    def test_spawn_missing_exe(self):
+        with self.assertRaises(DistutilsExecError) as ctx:
+            spawn(['does-not-exist'])
+            assert 'command does-no-exist failed' in str(ctx)
+
 
 def test_suite():
     return unittest.makeSuite(SpawnTestCase)