Add additional checks and tests

src/nomad_measurements/utils.py

@@ -126,6 +126,12 @@ def to_pint_quantity(value: Any=None, unit: str=None) -> Any:
     Returns:
         Any: Processed quantity with datatype depending on the value.
     '''
-    if isinstance(value, str):
+    if isinstance(value, str) or value is None:
         return value
+    if unit is None:
+        if isinstance(value, ureg.Quantity):
+            return value
+        return value * ureg.dimensionless
+    if isinstance(value, ureg.Quantity):
+        return value.to(unit)
     return value * ureg(unit)

tests/test_utils.py

@@ -56,12 +56,20 @@ def test_merge_sections():
     assert system_3.components[0].name == 'Cu'
 
 def test_to_pint_quantity():
-    assert to_pint_quantity(1, 'mA') == 1 * ureg.mA
-    assert str(to_pint_quantity(np.asarray([1., 2.]), 'm')) \
-        == str(np.asarray([1., 2.]) * ureg.m)
-    assert str(to_pint_quantity(np.asarray([1., 2.]), '')) \
-        == str(np.asarray([1., 2.]))
+    assert to_pint_quantity(None, '') is None
+    assert to_pint_quantity(None, None) is None
+    assert to_pint_quantity(None, 'mA') is None
     assert to_pint_quantity('Copper', '') == 'Copper'
+    assert to_pint_quantity('Copper', 'mA') == 'Copper'
+    assert to_pint_quantity(3., None) == 3 * ureg.dimensionless
+    assert to_pint_quantity(3. * ureg.m, None) == 3 * ureg.m
+    assert to_pint_quantity(3. * ureg.m, 'cm') == 300 * ureg.cm
+    assert to_pint_quantity(1, None) == 1
+    assert (to_pint_quantity(np.asarray([1., 2.]), 'm') \
+        == np.asarray([1., 2.]) * ureg.m).all()
+    assert (to_pint_quantity(np.asarray([1., 2.]), '') \
+        == np.asarray([1., 2.]) * ureg.dimensionless).all()
+    assert to_pint_quantity(1, 'mA') == 1 * ureg.mA
 
 if __name__ == '__main__':
     test_merge_sections()