Add cypress tests for alphabetical index Vue component

[UnniKohonen]

Reasons for creating this PR

Alphabetical index has no cypress tests, this PR adds them.

Link to relevant issue(s), if any

• Part of Implement alphabetical view in sidebar using Vue #1563

Description of the changes in this PR

• Added cypress tests for tab-alpha Vue component
• Added a new test vocab for testing loading on scroll

Addresses requirement 6 in #1563

Known problems or uncertainties in this PR

Checklist

• phpUnit tests pass locally with my changes
• I have added tests that show that the new code works, or tests are not relevant for this PR (e.g. only HTML/CSS changes)
• The PR doesn't reduce accessibility of the front-end code (e.g. tab focus, scaling to different resolutions, use of .sr-only class, color contrast)
• The PR doesn't introduce unintended code changes (e.g. empty lines or useless reindentation)

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 70.66%. Comparing base (12af8f3) to head (ade6442).
Report is 9 commits behind head on main.

Additional details and impacted files

@@             Coverage Diff              @@
##               main    #1688      +/-   ##
============================================
- Coverage     70.70%   70.66%   -0.05%     
  Complexity     1651     1651              
============================================
  Files            33       33              
  Lines          4332     4332              
============================================
- Hits           3063     3061       -2     
- Misses         1269     1271       +2     

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[osma]

The existing tests look good. A few thoughts below.

I think there could also be a test that checks for altLabels that should appear in the index. For example in the YSO Archaeology test vocabulary, there is this altLabel entry: artefacts → articles (inanimate objects)

Also, would it be a good idea to check the links to concepts as well? For example verify that the target URL is correct and/or simulate a click and verify that the concept is loaded. OTOH, there are tests like this already in vocab-home.cy.js so maybe there is no need to duplicate those. Maybe the vocab-home.cy.js tests could be moved alongside these, since they exercise the hierarchy sidebar?

All the new sidebar-related tests are now in sidebar.cy.js. This file may grow quite big since the sidebar has several components and more will be added later. Would it make sense to split it already now into e.g. sidebar-alpha.cy.js, sidebar-hierarchy.cs.js etc?

[osma]

LGTM!

[sonarcloud]

Quality Gate failed

Failed conditions
3 Security Hotspots

See analysis details on SonarCloud