Fix behavior in removeObserver. #349
Merged
Conversation
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
The change I made to allow `None` to indicate "please remove everything that observer is watching in observable" had a logic flaw.
- In `addObserver`, `notification=None` means "send every notification to this observer for this observable".
- In `removeObserver`, `notification` means "remove every registered notification from this observable for this observer".
Those seem alike, but this example shows my mistake:
```python
er = This()
able = That()
able.addObserver(observer=er, notification=None, method="anyNotificationHappened")
able.addObserver(observer=er, notification="specific", method="specificNotificationHappened")
able.removeObserver(observer=er, notification=None)
```
The `notification=None` has two conflicting meanings:
1. Remove the notification that will call method `er.anyNotificationHappened`.
2. Remove all observations for er.
- `er.anyNotificationHappened`
- `er.specificNotificationHappened`
Being able to vigorously remove observations without knowing specific notifications is useful, but the previous behavior is more important. So, I'm introducing an "all" option for `notification` to provide the new functionality without changing the old.
|
Ugh. Failed a test. Working on it. |
…ometimes things (cough tests cough) remove things that haven't been registered.
|
Failing tests fixed. |
typemytype
approved these changes
Mar 11, 2021
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
The change I made to allow
Noneto indicate "please remove everything that observer is watching in observable" had a logic flaw.addObserver,notification=Nonemeans "send every notification to this observer for this observable".removeObserver,notificationmeans "remove every registered notification from this observable for this observer".Those seem alike, but this example shows my mistake:
The
notification=Nonehas two conflicting meanings:er.anyNotificationHappened.er.anyNotificationHappeneder.specificNotificationHappenedBeing able to vigorously remove observations without knowing specific notifications is useful, but the previous behavior is more important. So, I'm introducing an "all" option for
notificationto provide the new functionality without changing the old.