Revert removal of test_get_flag

test/framework/toolchain.py

@@ -3237,6 +3237,21 @@ def test_env_vars_external_module(self):
         expected = {}
         self.assertEqual(res, expected)
 
+    def test_get_flag(self):
+        """Test get_flag function"""
+        tc = self.get_toolchain('gompi', version='2018a')
+
+        checks = {
+            '-a': '-a',
+            '-openmp': '-openmp',
+            '-foo': ['-foo'],
+            '-foo -bar': ['-foo', '-bar'],
+        }
+
+        for flagstring, flags in checks.items():
+            tc.options.options_map['openmp'] = flags
+            self.assertEqual(tc.get_flag('openmp'), flagstring)
+
 
 def suite():
     """ return all the tests"""