Add logic to enforce policy parameter 'validations'

RELEASES.md

@@ -13,7 +13,9 @@ Release 0.9.3 on 2017-??-??
 - None
 
 **New Features**
-- None
+- Add validation checking of policy parameters involved in a reform
+  [[#1502](https://github.com/open-source-economics/Tax-Calculator/pull/1502)
+  by Martin Holmer]
 
 **Bug Fixes**
 - None

taxcalc/current_law_policy.json

@@ -567,8 +567,7 @@
                   1000,
                   1050,
                   1050,
-                  1050],
-        "validations": {"min": "default"}
+                  1050]
     },
 
     "_STD_Aged": {
@@ -592,8 +591,7 @@
                   [1550, 1200, 1200, 1550, 1550],
                   [1550, 1250, 1250, 1550, 1550],
                   [1550, 1250, 1250, 1550, 1550],
-                  [1550, 1250, 1250, 1550, 1550]],
-        "validations": {"min": "default"}
+                  [1550, 1250, 1250, 1550, 1550]]
     },
 
     "_STD_allow_charity_ded_nonitemizers": {
@@ -757,7 +755,7 @@
         "col_var": "",
         "col_label": "",
         "value": [0.1],
-        "validations": {"min": "default"}
+        "validations": {"min": 0.1}
     },
 
     "_ID_Medical_frt_add4aged": {
@@ -959,7 +957,7 @@
         "col_var": "",
         "col_label": "",
         "value": [0.5],
-        "validations": {"max": "default"}
+        "validations": {"max": 0.5}
     },
 
     "_ID_Charity_crt_noncash": {
@@ -976,7 +974,7 @@
         "col_var": "",
         "col_label": "",
         "value": [0.3],
-        "validations": {"max": "default"}
+        "validations": {"max": 0.3}
     },
 
     "_ID_Charity_frt": {
@@ -993,7 +991,7 @@
         "col_var": "",
         "col_label": "",
         "value": [0.0],
-        "validations": {"min": "default"}
+        "validations": {"min": 0.0}
     },
 
 
@@ -1051,7 +1049,7 @@
         "col_var": "",
         "col_label": "",
         "value": [0.1],
-        "validations": {"min": "default"}
+        "validations": {"min": 0.1}
     },
 
     "_ID_Casualty_hc": {
@@ -1108,7 +1106,7 @@
         "col_var": "",
         "col_label": "",
         "value": [0.02],
-        "validations": {"min": "default"}
+        "validations": {"min": 0.02}
     },
 
     "_ID_Miscellaneous_hc": {

taxcalc/policy.py

@@ -5,6 +5,8 @@
 # pep8 --ignore=E402 policy.py
 # pylint --disable=locally-disabled policy.py
 
+import six
+import numpy as np
 from taxcalc.parameters import ParametersBase
 from taxcalc.growfactors import Growfactors
 
@@ -187,6 +189,7 @@ def implement_reform(self, reform):
             self.set_year(year)
             self._update({year: reform[year]})
         self.set_year(precall_current_year)
+        self._validate_parameter_values()
 
     def current_law_version(self):
         """
@@ -215,3 +218,65 @@ def translate_json_reform_suffixes(jsonstr):
         and return the consolidated JSON string
         """
         return jsonstr  # TODO temporary code
+
+    # ----- begin private methods of Policy class -----
+
+    VALIDATED_PARAMETERS = set([
+        '_II_credit_prt',
+        '_II_credit_nr_prt',
+        '_ID_Medical_frt_add4aged',
+        '_II_brk1',
+        '_II_brk2',
+        '_II_brk3',
+        '_II_brk4',
+        '_II_brk5',
+        '_II_brk6',
+        '_II_brk7',
+        '_PT_brk1',
+        '_PT_brk2',
+        '_PT_brk3',
+        '_PT_brk4',
+        '_PT_brk5',
+        '_PT_brk6',
+        '_PT_brk7',
+        '_CTC_new_refund_limit_payroll_rt',
+        '_FST_AGI_trt',
+        '_FST_AGI_thd_lo',
+        '_FST_AGI_thd_hi',
+        '_AGI_surtax_trt',
+        '_STD',
+        '_ID_Casualty_frt',
+        '_ID_Charity_crt_all',
+        '_ID_Charity_crt_noncash',
+        '_ID_Charity_frt',
+        '_ID_Medical_frt',
+        '_ID_Miscellaneous_frt'
+    ])
+
+    def _validate_parameter_values(self):
+        """
+        Check policy parameter values using validations information from
+        the current_law_policy.json file.
+        """
+        clp = self.current_law_version()
+        syr = Policy.JSON_START_YEAR
+        for pname in Policy.VALIDATED_PARAMETERS:
+            pvalue = getattr(self, pname)
+            for vop, vval in self._vals[pname]['validations'].items():
+                if isinstance(vval, six.string_types):
+                    if vval == 'default':
+                        vvalue = getattr(clp, pname)
+                    else:
+                        vvalue = getattr(self, vval)
+                else:
+                    vvalue = np.full(pvalue.shape, vval)
+                assert pvalue.shape == vvalue.shape
+                for idx in np.ndindex(pvalue.shape):
+                    if vop == 'min' and pvalue[idx] < vvalue[idx]:
+                        msg = '{} {} value {} < min value {}'
+                        raise ValueError(msg.format(idx[0] + syr, pname,
+                                                    pvalue[idx], vvalue[idx]))
+                    if vop == 'max' and pvalue[idx] > vvalue[idx]:
+                        msg = '{} {} value {} > max value {}'
+                        raise ValueError(msg.format(idx[0] + syr, pname,
+                                                    pvalue[idx], vvalue[idx]))

taxcalc/tests/test_policy.py

@@ -1,5 +1,6 @@
 import os
 import sys
+import six
 import json
 import tempfile
 import numpy as np
@@ -52,7 +53,7 @@ def test_correct_Policy_instantiation():
 def test_policy_json_content():
     ppo = Policy()
     policy = getattr(ppo, '_vals')
-    for name, data in policy.items():
+    for _, data in policy.items():
         start_year = data.get('start_year')
         assert isinstance(start_year, int)
         assert start_year == Policy.JSON_START_YEAR
@@ -364,10 +365,10 @@ def test_implement_reform_Policy_raises_on_no_year():
 
 def test_Policy_reform_in_start_year():
     ppo = Policy(start_year=2013)
-    reform = {2013: {'_STD_Aged': [[1400, 1100, 1100, 1400, 1400]]}}
+    reform = {2013: {'_STD': [[16000, 13000, 13000, 16000, 16000]]}}
     ppo.implement_reform(reform)
-    assert_allclose(ppo.STD_Aged,
-                    np.array([1400, 1100, 1100, 1400, 1400]),
+    assert_allclose(ppo.STD,
+                    np.array([16000, 13000, 13000, 16000, 16000]),
                     atol=0.01, rtol=0.0)
 
 
@@ -747,3 +748,56 @@ def test_json_reform_suffixes(tests_path):
     unmatched = suffixes ^ Policy.JSON_REFORM_SUFFIXES
     if len(unmatched) != 0:
         assert unmatched == 'UNMATCHED SUFFIXES'
+
+
+def test_validated_parameters_set(tests_path):
+    """
+    Check Policy.VALIDATED_PARAMETERS against current_law_policy.json info.
+    """
+    # read current_law_policy.json file into a dictionary
+    path = os.path.join(tests_path, '..', 'current_law_policy.json')
+    clpfile = open(path, 'r')
+    clpdict = json.load(clpfile)
+    clpfile.close()
+    # construct set of parameter names with "validations" field in clpdict
+    json_validated_params = set()
+    for pname in clpdict:
+        param = clpdict[pname]
+        assert isinstance(param, dict)
+        valid = param.get('validations', None)
+        if valid:
+            json_validated_params.add(pname)
+            for vop, vval in valid.items():
+                assert vop in ['min', 'max']
+                if isinstance(vval, six.string_types):
+                    if vval == 'default':
+                        continue
+                    elif vval in clpdict:
+                        continue
+                    else:
+                        assert vval == 'ILLEGAL VALIDATION STRING VALUE'
+                else:
+                    if isinstance(vval, int):
+                        continue
+                    elif isinstance(vval, float):
+                        continue
+                    else:
+                        assert vval == 'ILLEGAL VALIDATION NUMERIC VALUE'
+    # compare contents of Policy.VALIDATED_PARAMETERS and json_validated_params
+    unmatched = Policy.VALIDATED_PARAMETERS ^ json_validated_params
+    if len(unmatched) != 0:
+        assert unmatched == 'UNMATCHED VALIDATED PARAMETERS'
+
+
+def test_validate_param_values_errors():
+    """
+    Check detection of failures of min and max validations.
+    """
+    pol1 = Policy()
+    ref1 = {2020: {'_ID_Medical_frt': [0.05]}}
+    with pytest.raises(ValueError):
+        pol1.implement_reform(ref1)
+    pol2 = Policy()
+    ref2 = {2021: {'_ID_Charity_crt_all': [0.60]}}
+    with pytest.raises(ValueError):
+        pol2.implement_reform(ref2)

taxcalc/tests/test_reforms.py

@@ -612,15 +612,15 @@ def test_r25(puf_subsample):
     reform_json = """
     {
         "start_year": 2015,
-        "value": {"_ID_Miscellaneous_frt": [0.01]},
-        "name": "Lower AGI floor for miscellaneous itemded by 1 pts",
+        "value": {"_ID_Miscellaneous_frt": [0.03]},
+        "name": "Increase AGI floor for miscellaneous itemded by 1 pts",
         "output_type": "iitax",
         "compare_with": {}
     }
     """
-    expected_res = ('Lower AGI floor for miscellaneous itemded by 1 pts'
+    expected_res = ('Increase AGI floor for miscellaneous itemded by 1 pts'
                     '\n'
-                    'Tax-Calculator,-2.9,-3.0,-3.1,-3.3')
+                    'Tax-Calculator,2.1,2.2,2.3,2.4')
     actual_res = reform_results(json.loads(reform_json), puf_subsample)
     assert actual_res == expected_res