ui5-tabcontainer throws error when rendered without tabs

[MarcusNotheis]

Bug Description

The ui5-tabcontainer throws an error when being rendered without tabs. This can be the case when tabs are lazy loaded or generated during runtime.

Expected Behavior

Does not crash (like in 1.6.0).

Steps to Reproduce

1. Open CodeSandBox: https://codesandbox.io/s/keen-sunset-76d1cu?file=/src/App.js
2. Optional: If you downgrade to UI5 Web Components 1.6.0 it's working fine

Isolated Example

https://codesandbox.io/s/keen-sunset-76d1cu?file=/src/App.js

Context

• UI5 Web Components version: 1.7.0
• Affected component: ui5-tabcontainer

Log Output / Stack Trace / Screenshots

Priority

• Low
• Medium
• High
• Very High

Regression from 1.6.0

Stakeholder Info (if applicable)

• Organization: UI5 Web Components for React
• Business impact: Blocking update to 1.7.0

[nnaydenow]

Hello @SAP/ui5-webcomponents-topic-rd,

The default value of _selectedTab is empty object ( {} ) by default. When items slot is empty _getRootTab method is called with empty object as parameter and this leads to an error.

The in the provided example initially the ui5-tab-container is empty and its children elements still not added.

Could you please check this issue?

Regards,
Nayden

[TeodorTaushanov]

The issue is fixed in the main branch.