fix: Correctly determine holdsState in onlyTime mode to prevent result removal

[xxxinsxxx]

🧠 Problem Summary

In only="time" mode, the original logic of the holdsState() method was:

if (self.onlyTime && !isDefined(self.time)) return false;
return isDefined(self.month) || isDefined(self.year);

During the first time selecting a time:

• self.time is assigned;
• updateResult() triggers createPerObjectResult(), successfully creating the result.

However, during the second time modifying the time:

• self.time is assigned;
• updateResult() triggers self.result.area.setValue(self);
• It enters setValue(tag)；
• The tag.holdsState is evaluated to determine whether to keep the result；
• Since !isDefined(self.time) is false, it falls through to return isDefined(self.month) || isDefined(self.year)；
• In only="time" mode, month and year are always undefined, so holdsState returns false；
• As a result, setValue(tag) calls removeResult(result), removing the result, causing the bug where the input disappears after being set.

Changing the value again after that is just repeating this process.This behavior leads to an incorrect state evaluation that breaks expected functionality.

The involved files include: DateTime.jsx, ClassificationBase.js, AreaMixin.js

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Description:

In only="time" mode, the previous logic of holdsState() caused a regression where time updates would be discarded unexpectedly. The original condition:

if (self.onlyTime && !isDefined(self.time)) return false;
return isDefined(self.month) || isDefined(self.year);

would fall through to checking month and year, which are always undefined in only="time" mode, leading to an incorrect false return value. This resulted in the result being removed during subsequent time changes.

This change simplifies and corrects the logic:

if (self.onlyTime) return isDefined(self.time);
return isDefined(self.month) || isDefined(self.year);

Now, in only="time" mode, the state is solely determined by whether self.time is defined — aligning with the intended behavior and preventing unintended result removal.

---

🔍Problem Solved:

• fix Datetime Tag with only="time" Parameter Fails to Display Selected Value #7628

before:

after:

---

📁 Changed Files

Path: libs/editor/src/tags/control/DateTime.jsx

Code Changes:

 get holdsState() {
-  if (self.onlyTime && !isDefined(self.time)) return false;
-  return isDefined(self.month) || isDefined(self.year);
+  if (self.onlyTime) return isDefined(self.time);
+  return isDefined(self.month) || isDefined(self.year);
 },

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✅ Testing Recommendation:

• Test time input on odd/even updates.
• Ensure results persist in only="time" mode.
• Validate behavior in other modes.
• Verify mixed-mode behavior.

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