Fix #13737: Voiceover does not repeat when user submits answer before voiceover has finished

[murraytay]

Overview

1. This PR fixes or fixes part of Audio mismatch after answering a question #13737.
2. This PR does the following: Makes sure that when a user submits and answer before the voiceover has finished, the voiceover does not repeat the audio it was playing. This includes two parts: 1) making sure the voiceover moves on to the secondary audio or 2) making sure the voiceover outputs nothing when there is no audio for the secondary text.

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Proof that changes are correct

No voiceover for secondary text (make sure first text does not repeat)

no_secondary_audio.mov

Voiceover for secondary text

secondary_audio.mov

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[oppiabot]

Hi @kevintab95, @DubeySandeep -- could one of you please add the appropriate changelog label to this pull request? Thanks!

[murraytay]

Important context:

In this PR I make a fundamental change to the stop audio functionality: instead of simply stopping the track, I mimic the behavior of the on audio track ended callback function and set the currentTrack, filename, and position in file to null and call clearSecondaryAudioTranslations. I think having Stop be similar to 'on end' makes sense but it also may make the distinction between the Stop and Cancel functions irrelevant. Currently, the cancel function calls the stop function and then sets currentTrackFilename and currentTrack to be null, so in the new implementation it never makes sense to call cancel.

Please look to these changes: https://github.com/oppia/oppia/pull/3818/files to see the old implementation of the stop, clear, and on ended functions, which used to look a lot like what my new edits are (stop didn't actually Stop the file, it just set it to null). I am not sure why this change was made, and have made one of my commits just so you can see where Stop is called and why. It is my opinion that none of the current uses of Stop actually require it to behave differently than cancel so it might actually just be a good idea to get rid of cancel.

[oppiabot]

Hi @murraytay, the build of this PR is stale and this could result in tests failing in develop. Please update this pull request with the latest changes from develop. Thanks!

[DubeySandeep]

@kevintab95 Can you please review this PR as a primary reviewer?

[oppiabot]

Hi @murraytay, there is a new change in develop which needs to be in your PR. Please update your branch with the latest changes in develop. For instructions, refer to this link. Thanks!

[murraytay]

@kevintab95 would you mind reviewing this PR?

[oppiabot]

Hi @murraytay, the build of this PR is stale and this could result in tests failing in develop. Please update this pull request with the latest changes from develop. Thanks!

[murraytay]

@DubeySandeep please see my comments to your message!

[oppiabot]

Hi @murraytay, I'm going to mark this PR as stale because it hasn't had any updates for 7 days. If no further activity occurs within 4 days, it will be automatically closed so that others can take up the issue.
If you are still working on this PR, please make a follow-up commit within 4 days (and submit it for review, if applicable). Please also let us know if you are stuck so we can help you!

[murraytay]

PTAL @DubeySandeep

[murraytay]

done

[murraytay]

Ok, so on further inspection it seems to just need the currentTrack.stop() function which I think makes sense without a comment. Let me know what you think!

[murraytay]

done

[oppiabot]

Unassigning @DubeySandeep since they have already approved the PR.

[oppiabot]

Hi @aks681, this PR is ready to be merged. Author of this PR does not have permissions to merge this PR. Before you merge it, please make sure that there are no pending comments that require action from the author's end. Thanks!