fix: properly delete field

src/super-tag/widgets/utils/formOnChange.ts

@@ -4,7 +4,7 @@ export function formOnChange(currentTiddlerTitle?: string, editor?: JSONEditor.J
   if (currentTiddlerTitle === undefined || editor === undefined) return;
   const latestFormValue = editor?.getValue() as Record<string, unknown>;
   if (latestFormValue === undefined || latestFormValue === null) {
-      return;
+    return;
   }
   // Get an array of errors from the validator
   const errors = editor.validate();
@@ -13,22 +13,22 @@ export function formOnChange(currentTiddlerTitle?: string, editor?: JSONEditor.J
       errorValidatorInfoElement.className = 'label label-warning';
       errorValidatorInfoElement.textContent = 'Form not valid';
     }
-    return
-  } else {
-    const tiddlerFields = $tw.wiki.getTiddler(currentTiddlerTitle)?.fields ?? ({} as Record<string, unknown>);
+  }
+  let tiddlerFields = $tw.wiki.getTiddler(currentTiddlerTitle)?.fields ?? ({} as Record<string, unknown>);
 
-    let hasChange = false;
-    Object.keys(latestFormValue).forEach((key) => {
-      if (tiddlerFields[key] !== latestFormValue[key]) {
-        hasChange = true;
-        // if user delete the value from the form, also delete the field.
-        if (tiddlerFields[key] && !latestFormValue[key]) {
-          delete tiddlerFields[key];
-        }
+  let hasChange = false;
+  Object.keys(latestFormValue).forEach((key) => {
+    if (tiddlerFields[key] !== latestFormValue[key]) {
+      hasChange = true;
+      // if user delete the value from the form, also delete the field.
+      if (tiddlerFields[key] !== undefined && !latestFormValue[key]) {
+        const { [key]: _, ...tiddlerFieldsWithoutKey } = tiddlerFields;
+        tiddlerFields = tiddlerFieldsWithoutKey;
+        delete latestFormValue[key];
       }
-    });
-    if (hasChange) {
-      $tw.wiki.addTiddler({ ...tiddlerFields, ...latestFormValue, title: currentTiddlerTitle });
     }
+  });
+  if (hasChange) {
+    $tw.wiki.addTiddler({ ...tiddlerFields, ...latestFormValue, title: currentTiddlerTitle });
   }
 }