Merge pull request #44 from calogica/fix/issue-41

Adds better support for integer division issue in equal_expression macro
calogica · Apr 19, 2021 · fd8985f · fd8985f
2 parents 1a9f0fb + 3478249
commit fd8985f
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Showing 4 changed files with 31 additions and 11 deletions.
diff --git a/integration_tests/models/schema_tests/schema.yml b/integration_tests/models/schema_tests/schema.yml
@@ -136,6 +136,12 @@ models:
             expression: sum(col_numeric_a)
             compare_model: ref("data_test")
             group_by: [idx]
+        - dbt_expectations.equal_expression:
+            expression: sum(col_numeric_a)
+            compare_expression: sum(col_numeric_a * .5)
+            compare_model: ref("data_test")
+            group_by: [idx]
+            tolerance_percent: .5
         - dbt_expectations.expect_column_pair_values_to_be_in_set:
             column_A: col_numeric_a
             column_B: col_numeric_b

diff --git a/macros/schema_tests/_generalized/equal_expression.sql b/macros/schema_tests/_generalized/equal_expression.sql
@@ -29,27 +29,34 @@
                                 row_condition=None,
                                 compare_row_condition=None,
                                 tolerance=0.0,
-                                tolerance_percent=None) -%}
-    {{ adapter.dispatch('test_equal_expression', packages = dbt_expectations._get_namespaces()) (model, expression,
+                                tolerance_percent=None,
+                                return_difference=False
+                                ) -%}
+
+    {{ adapter.dispatch('test_equal_expression', packages = dbt_expectations._get_namespaces()) (
+                                model, expression,
                                 compare_model,
                                 compare_expression,
                                 group_by,
                                 compare_group_by,
                                 row_condition,
                                 compare_row_condition,
                                 tolerance,
-                                tolerance_percent) }}
+                                tolerance_percent,
+                                return_difference) }}
 {%- endmacro %}
 
-{%- macro default__test_equal_expression(model, expression,
+{%- macro default__test_equal_expression(
+                                model, expression,
                                 compare_model,
                                 compare_expression,
                                 group_by,
                                 compare_group_by,
                                 row_condition,
                                 compare_row_condition,
                                 tolerance,
-                                tolerance_percent) -%}
+                                tolerance_percent,
+                                return_difference) -%}
 
     {%- set compare_model = model if not compare_model else compare_model -%}
     {%- set compare_expression = expression if not compare_expression else compare_expression -%}
@@ -73,7 +80,7 @@
             b.expression as compare_expression,
             abs(coalesce(a.expression, 0) - coalesce(b.expression, 0)) as expression_difference,
             abs(coalesce(a.expression, 0) - coalesce(b.expression, 0))/
-                nullif(a.expression, 0) as expression_difference_percent
+                nullif(a.expression * 1.0, 0) as expression_difference_percent
         from
             a
             full outer join
@@ -84,10 +91,17 @@
     )
     -- DEBUG:
     -- select * from final
-    select count(*) from final
+    select
+        {% if return_difference %}
+        coalesce(sum(expression_difference), 0)
+        {% else %}
+        count(*)
+        {% endif %}
+    from final
     where
-        expression_difference > {{ tolerance }}
         {% if tolerance_percent %}
-        and expression_difference_percent > {{ tolerance_percent }}
+        expression_difference_percent > {{ tolerance_percent }}
+        {% else %}
+        expression_difference > {{ tolerance }}
         {% endif %}
 {%- endmacro -%}
diff --git a/...os/schema_tests/table_shape/expect_table_row_count_to_equal_other_table _times_factor.sql b/...os/schema_tests/table_shape/expect_table_row_count_to_equal_other_table _times_factor.sql
@@ -1,3 +1,3 @@
 {%- macro test_expect_table_row_count_to_equal_other_table_times_factor(model, compare_model, factor) -%}
-{{ dbt_expectations.test_equal_expression(model, "count(*)", compare_model=compare_model, compare_expression="count(*) * " + factor|string) }}
+{{ dbt_expectations.test_equal_expression(model, "count(*)", compare_model=compare_model, compare_expression="count(*) * " + factor|string, return_difference=True) }}
 {%- endmacro -%}
diff --git a/macros/schema_tests/table_shape/expect_table_row_count_to_equal_other_table.sql b/macros/schema_tests/table_shape/expect_table_row_count_to_equal_other_table.sql
@@ -1,3 +1,3 @@
 {%- macro test_expect_table_row_count_to_equal_other_table(model, compare_model) -%}
-{{ dbt_expectations.test_equal_expression(model, "count(*)", compare_model=compare_model) }}
+{{ dbt_expectations.test_equal_expression(model, "count(*)", compare_model=compare_model, return_difference=True) }}
 {%- endmacro -%}