Fix qcfilter.add_test index (#712)

* Fix erroneous flag for scalar qc and boolean index

* Add test for scalar variables

* Add one more check for default index=None

act/qc/qcfilter.py

@@ -553,7 +553,7 @@ def set_test(self, var_name, index=None, test_number=None, flag_value=False):
             if flag_value:
                 qc_variable[index] = test_number
             else:
-                if np.size(qc_variable) > 1:
+                if bool(np.shape(index)):
                     qc_variable[index] = set_bit(qc_variable[index], test_number)
                 elif index == 0:
                     qc_variable = set_bit(qc_variable, test_number)

act/tests/test_qc.py

@@ -201,6 +201,45 @@ def test_qcfilter():
         == 0
     )
 
+    # Test adding QC for length-1 variables
+    ds['west'] = ('west', ['W'])
+    ds['avg_wind_speed'] = ('west', [20])
+
+    # Should not fail the test
+    ds.qcfilter.add_test(
+        'avg_wind_speed',
+        index=ds.avg_wind_speed.data > 100,
+        test_meaning='testing bool flag: false',
+        test_assessment='Suspect',
+    )
+    assert ds.qc_avg_wind_speed.data == 0
+
+    # Should fail the test
+    ds.qcfilter.add_test(
+        'avg_wind_speed',
+        index=ds.avg_wind_speed.data < 100,
+        test_meaning='testing bool flag: true',
+        test_assessment='Suspect',
+    )
+    assert ds.qc_avg_wind_speed.data == 2
+
+    # Should fail the test
+    ds.qcfilter.add_test(
+        'avg_wind_speed',
+        index=[0],
+        test_meaning='testing idx flag: true',
+        test_assessment='Suspect',
+    )
+    assert ds.qc_avg_wind_speed.data == 6
+
+    # Should not fail the test
+    ds.qcfilter.add_test(
+        'avg_wind_speed',
+        test_meaning='testing idx flag: false',
+        test_assessment='Suspect',
+    )
+    assert ds.qc_avg_wind_speed.data == 6
+
     # Unset a test
     ds.qcfilter.unset_test(var_name, index=0, test_number=result['test_number'])
     # Remove the test