Allow FormulaWidget column to be undefined when using COUNT

CHANGELOG.md

@@ -2,6 +2,8 @@
 
 ## Not released
 
+- Allow FormulaWidget column to be undefined when using COUNT [#434](https://github.com/CartoDB/carto-react/pull/434)
+
 ## 1.3
 
 ### 1.3.0-beta.1 (2022-06-14)

packages/react-widgets/src/widgets/FormulaWidget.js

@@ -3,7 +3,7 @@ import { PropTypes } from 'prop-types';
 import { WrapperWidgetUI, FormulaWidgetUI } from '@carto/react-ui';
 import { getFormula } from '../models';
 import { AggregationTypes } from '@carto/react-core';
-import { columnAggregationOn } from './utils/propTypesFns';
+import { checkFormulaColumn, columnAggregationOn } from './utils/propTypesFns';
 import useWidgetFetch from '../hooks/useWidgetFetch';
 import WidgetWithAlert from './utils/WidgetWithAlert';
 
@@ -76,8 +76,7 @@ FormulaWidget.propTypes = {
   id: PropTypes.string.isRequired,
   title: PropTypes.string.isRequired,
   dataSource: PropTypes.string.isRequired,
-  column: PropTypes.oneOfType([PropTypes.string, PropTypes.arrayOf(PropTypes.string)])
-    .isRequired,
+  column: checkFormulaColumn,
   joinOperation: columnAggregationOn('column'),
   operation: PropTypes.oneOf(Object.values(AggregationTypes)).isRequired,
   formatter: PropTypes.func,

packages/react-widgets/src/widgets/utils/propTypesFns.js

@@ -12,3 +12,27 @@ export const columnAggregationOn = (columnPropName) => (props, propName) => {
     }
   }
 };
+
+// FormulaWidget
+export const checkFormulaColumn = (props, propName) => {
+  const propValue = props[propName];
+
+  const isValidString = !!propValue && typeof propValue === 'string';
+  const isValidArray = Array.isArray(propValue) && propValue.length;
+
+  const validationError = new Error(`Prop ${propName} must be a string or an array`);
+
+  if (props.operation === AggregationTypes.COUNT) {
+    if (propValue && !(isValidString || isValidArray)) {
+      return validationError;
+    }
+  } else {
+    if (!propValue) {
+      return new Error(`Prop ${propName} must be defined`);
+    }
+
+    if (!isValidArray || !isValidString) {
+      return validationError;
+    }
+  }
+};

packages/react-workers/src/workers/features.worker.js

@@ -106,11 +106,17 @@ function getFormula({
   if (currentFeatures) {
     const targetOperation = aggregationFunctions[operation];
 
-    assertColumn(column);
+    const isCount = operation === AggregationTypes.COUNT;
+
+    // If the operation isn't count, we need to assert the column
+    // If the operation is count, the column can be undefined
+    if (!isCount || (isCount && column)) {
+      assertColumn(column);
+    }
 
     const filteredFeatures = getFilteredFeatures(filters, filtersLogicalOperator);
 
-    if (filteredFeatures.length === 0 && operation !== AggregationTypes.COUNT) {
+    if (filteredFeatures.length === 0 && !isCount) {
       result = { value: null };
     } else {
       result = { value: targetOperation(filteredFeatures, column, joinOperation) };