🐛 allow single-entity selection for charts split by metric

db/migration/1737580227406-RetainMultiEntitySelectionForChartsSplitByMetric.ts

@@ -0,0 +1,48 @@
+import { MigrationInterface, QueryRunner } from "typeorm"
+
+// As part of the migration, we'll update all charts that are split by metric
+// and have a 'change-country' setting to use the 'add-country' setting instead.
+// These charts should be excluded from the migration since the 'change-country'
+// is more appropriate for them.
+const slugs = [
+    "cancer-death-rates-by-age",
+    "neonatal-deaths-by-cause",
+    "dealing-with-anxiety-depression-approaches",
+    "mental-illness-estimated-cases",
+    "deaths-from-cardiovascular-disease-type",
+    "country-level-monthly-temperature-anomalies",
+    "summer-temperature-anomalies",
+    "winter-temperature-anomalies",
+    "autumn-temperature-anomalies",
+    "spring-temperature-anomalies",
+    "5-year-survival-rate-of-cancers-among-female-patients-in-england",
+]
+
+export class RetainMultiEntitySelectionForChartsSplitByMetric1737580227406
+    implements MigrationInterface
+{
+    public async up(queryRunner: QueryRunner): Promise<void> {
+        // Charts faceted by metric used to ignore the 'change-country' setting
+        // and offer multi-entity selection always. The code change that comes
+        // with this migration makes it so that the 'change-country' setting
+        // is respected. This migration updates all existing charts that relied
+        // on the old behavior to use the 'add-country' setting explicitly.
+        await queryRunner.query(
+            `
+            UPDATE chart_configs
+            SET
+                patch = JSON_SET(patch, '$.addCountryMode', 'add-country'),
+                full = JSON_SET(full, '$.addCountryMode', 'add-country')
+            WHERE
+                full ->> '$.addCountryMode' = 'change-country'
+                AND full ->> '$.selectedFacetStrategy' = 'metric'
+                AND slug NOT IN (?);
+        `,
+            [slugs]
+        )
+    }
+
+    public async down(): Promise<void> {
+        // no-op
+    }
+}

packages/@ourworldindata/grapher/src/core/Grapher.tsx

@@ -3689,19 +3689,15 @@ export class Grapher
 
     @computed get canSelectMultipleEntities(): boolean {
         if (this.numSelectableEntityNames < 2) return false
+        if (this.selection.numSelectedEntities > 1) return true
         if (this.addCountryMode === EntitySelectionMode.MultipleEntities)
             return true
 
+        // if the chart is currently faceted by entity, then use multi-entity
+        // selection, even if the author specified single-entity-selection
         if (
-            // we force multi-entity selection mode when the chart is faceted
             this.addCountryMode === EntitySelectionMode.SingleEntity &&
-            this.facetStrategy !== FacetStrategy.none &&
-            // unless the author explicitly configured the chart to be split
-            // by metric and hid the facet control
-            !(
-                this.facetStrategy === FacetStrategy.metric &&
-                this.hideFacetControl
-            )
+            this.facetStrategy === FacetStrategy.entity
         )
             return true