Possible Bug with Touching Parent Timestamps

[AdenFraser]

• Laravel Version: 5.3.x
• PHP Version: 7.1
• Database Driver & Version: MySql

Description:

'Touches' updates touched models updated_at timestamp when child model performs an update with no dirty data (thus no updated_at change on child model).

Steps To Reproduce:

Using the example from the docs:
https://laravel.com/docs/5.4/eloquent-relationships#touching-parent-timestamps

Performing an update with no dirty data on the 'comment' model would result in the 'post' model's updated_at timestamp being updated, while the 'comment' model does not (due to it not being dirty).

Is this expected behaviour or a bug? Happy to put in a PR to fix, it's in the snippet below where the $saved = isDirty... ternary sets $saved to true when the data on the model isn't dirty... and thus finishSave() gets called which updates parent timestamps.

        // If the model already exists in the database we can just update our record
        // that is already in this database using the current IDs in this "where"
        // clause to only update this model. Otherwise, we'll just insert them.
        if ($this->exists) {
            $saved = $this->isDirty() ?
                        $this->performUpdate($query) : true;
        }

        // If the model is brand new, we'll insert it into our database and set the
        // ID attribute on the model to the value of the newly inserted row's ID
        // which is typically an auto-increment value managed by the database.
        else {
            $saved = $this->performInsert($query);
        }

        if ($saved) {
            $this->finishSave($options);
        }

[alexsoft]

I remember in some version upgrade guide (5.3 or 5.4) there was a note that save() method on model will return false if nothing changed. That I think would fix this behaviour. But I'm afraid this change on save() method was reverted.

[adiachenko]

Alternatively, we could perform $this->isDirty() check in finishSave() if always returning true from a save() method is expected behavior. Any comments on this?

Anyway, I think this is a bug:

• directly saving model without changing anything doesn't update timestamps
• saving model's relationship without changing anything updates timestamps

There is a clear inconsistency here.

[baceto90]

Its there are any fix for that problem?

[themsaid]

A fix was submitted in: #20489