bug #1944 [Chart.js] Listen to Stimulus disconnect event to destroy the chart (Shadow-Devil)

This PR was squashed before being merged into the 2.x branch.

Discussion
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[Chart.js] Listen to Stimulus `disconnect` event to destroy the chart

| Q             | A
| ------------- | ---
| Bug fix?      | yes
| New feature?  | no
| Issues        | Fix #1408
| License       | MIT

Adds an extra check if the chart is already connected and short circuits, since otherwise creating the new Chart would throw an error.

Commits
-------

22d1cee [Chart.js] Listen to Stimulus `disconnect` event to destroy the chart

Author: Kocal

src/Chartjs/CHANGELOG.md

@@ -1,5 +1,9 @@
 # CHANGELOG
 
+## 2.23.0
+
+-   Listen to Stimulus `disconnect` event to destroy the chart #1944
+
 ## 2.18.0
 
 -   Replace `chartjs/auto` import with explicit `Chart.register()` call #1263

src/Chartjs/assets/dist/controller.d.ts

@@ -6,6 +6,7 @@ export default class extends Controller {
     };
     private chart;
     connect(): void;
+    disconnect(): void;
     viewValueChanged(): void;
     private dispatchEvent;
 }

src/Chartjs/assets/dist/controller.js

@@ -35,6 +35,13 @@ class default_1 extends Controller {
         this.chart = new Chart(canvasContext, payload);
         this.dispatchEvent('connect', { chart: this.chart });
     }
+    disconnect() {
+        this.dispatchEvent('disconnect', { chart: this.chart });
+        if (this.chart) {
+            this.chart.destroy();
+            this.chart = null;
+        }
+    }
     viewValueChanged() {
         if (this.chart) {
             const viewValue = { data: this.viewValue.data, options: this.viewValue.options };

src/Chartjs/assets/src/controller.ts

@@ -57,6 +57,15 @@ export default class extends Controller {
         this.dispatchEvent('connect', { chart: this.chart });
     }
 
+    disconnect() {
+        this.dispatchEvent('disconnect', { chart: this.chart });
+
+        if (this.chart) {
+            this.chart.destroy();
+            this.chart = null;
+        }
+    }
+
     /**
      * If the underlying data or options change, let's update the chart!
      */