fix: should not change preventUpdatingModelValue when jsonEditor.value is empty

Author: cloydlau

src/Component.ts

@@ -125,16 +125,17 @@ export default defineComponent({
           preventUpdatingContent.value = false
           return
         }
-        preventUpdatingModelValue.value = true
-        // `jsonEditor.value` could be `undefined` in Vue 2.6 (dev environment)
-        jsonEditor.value?.set(
-          [undefined, ''].includes(newModelValue)
-            // `undefined` is not accepted by vanilla-jsoneditor
-            // The default value is `{ text: '' }`
-            // Only default value can clear the editor
-            ? { text: '' }
-            : { json: newModelValue },
-        )
+        if (jsonEditor.value) {
+          preventUpdatingModelValue.value = true
+          jsonEditor.value.set(
+            [undefined, ''].includes(newModelValue)
+              // `undefined` is not accepted by vanilla-jsoneditor
+              // The default value is `{ text: '' }`
+              // Only default value can clear the editor
+              ? { text: '' }
+              : { json: newModelValue },
+          )
+        }
       },
       {
         deep: true,