Merge pull request #38 from rbrtmrtn/constant-attribute-fn

Add constant attribute function and tests

openaddr/conform.py

@@ -803,6 +803,8 @@ def row_function(sc, row, key, fxn):
         row = row_fxn_chain(sc, row, key, fxn)
     elif function == "first_non_empty":
         row = row_fxn_first_non_empty(sc, row, key, fxn)
+    elif function == "constant":
+        row = row_fxn_constant(sc, row, key, key, fxn)
 
     return row
 
@@ -1031,6 +1033,14 @@ def row_fxn_first_non_empty(sc, row, key, fxn):
 
     return row
 
+def row_fxn_constant(sc, row, key, fxn):
+    "Set an attribute to a constant value"
+    value  = fxn['value']
+
+    row['oa:{}'.format(key)] = value
+
+    return row
+
 def row_canonicalize_unit_and_number(sc, row):
     "Canonicalize address unit and number"
     row["UNIT"] = (row["UNIT"] or '').strip()

openaddr/tests/conform.py

@@ -22,7 +22,7 @@
     row_fxn_prefixed_number, row_fxn_postfixed_street,
     row_fxn_postfixed_unit,
     row_fxn_remove_prefix, row_fxn_remove_postfix, row_fxn_chain,
-    row_fxn_first_non_empty,
+    row_fxn_first_non_empty, row_fxn_constant,
     row_canonicalize_unit_and_number, conform_smash_case, conform_cli,
     convert_regexp_replace, normalize_ogr_filename_case,
     is_in, geojson_source_to_csv, check_source_tests
@@ -1621,6 +1621,35 @@ def test_row_first_non_empty(self):
         d = row_fxn_first_non_empty(c, d, "street", c["conform"]["street"])
         self.assertEqual(e, d)
 
+    def test_row_fxn_constant(self):
+        "constant - replacing empty string"
+        c = { "conform": {
+            "region": {
+                "function": "constant",
+                "value": "PA"
+            }
+        } }
+        d = { "STATE": "" }
+        e = copy.deepcopy(d)
+        e.update({ "oa:region": "PA" })
+
+        d = row_fxn_constant(c, d, "region", c["conform"]["region"])
+        self.assertEqual(e, d)
+
+        "constant - replacing non-empty, non-standard string"
+        c = { "conform": {
+            "region": {
+                "function": "constant",
+                "value": "PA"
+            }
+        } }
+        d = { "STATE": "Penna" }
+        e = copy.deepcopy(d)
+        e.update({ "oa:region": "PA" })
+
+        d = row_fxn_constant(c, d, "region", c["conform"]["region"])
+        self.assertEqual(e, d)
+
 class TestConformCli (unittest.TestCase):
     "Test the command line interface creates valid output files from test input"
     def setUp(self):