Combobox - filter search is inconsistent between single and multi-select versions

[yashgarg17]

Title line template: [Title]: Brief description

For the Combobox component, there is an inconsistency observed while searching for options between single and multi-select versions.

Detailed description

Describe in detail the issue you're having.
There are primarily 2 versions of the Combobox component are available -
single-selection - https://angular.carbondesignsystem.com/?path=/story/components-combobox--basic
multi-selection - https://angular.carbondesignsystem.com/?path=/story/components-combobox--multi-select

We have observed inconsistent behaviour while applying same filter in both the versions.
In case of single-select, if the search value is not present, then all the options are displayed -

But in case of multi-select, if the searched value is not present, then no options are listed -

Filtering should be consistent across the versions.

Is this a feature request (new component, new icon), a bug, or a general issue?
BUG

Is this issue related to a specific component?
It is specific to Combobox component

What did you expect to happen? What happened instead? What would you like to see changed?

Expected behaviour -
If the searched value is not matching with any of the options available, then it should show nothing as in case of multi-select version of Combobox component

Actual behaviour -
In case of single-select, if the search value is not present, then all the options are displayed

What browser are you working in?
Chrome

What version of the Carbon Design System are you using?
4.36.1

What offering/product do you work on? Any pressing ship or release dates we should be aware of?
IBM Cloud Brokerage - Cost and Asset Management

Steps to reproduce the issue

1. Go to https://angular.carbondesignsystem.com/?path=/story/components-combobox--basic
2. Search for any text which is not matching with any of the options. For example - test
3. Observe that all the available options are displayed, even though test is not matching with any of the options

4. Now go to https://angular.carbondesignsystem.com/?path=/story/components-combobox--multi-select
5. Search for any text which is not matching with any of the options. For example - test
6. Observe that no option is displayed, because test is not matching with any of the options

[zvonimirfras]

Hi @yashgarg17, thank you for noticing.

The same behavior is observable in the reference implementation (single, multi), so that's by design.

If you think this should be changed, open an issue in https://github.com/carbon-design-system/carbon and reopen this issue with a link to the issue you opened there. :)

[yashgarg17]

As per your suggestion , I have opened an issue in https://github.com/carbon-design-system/carbon which can be found at -
carbon-design-system/carbon#7589

Since the behavior is inconsistent, therefore reopening the defect