Fix nav links of synonymous sub-headings under Associations

[louy2]

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Description of change

Added new transform fix-ids.js to fix sub-heading ids and links under Association.

Closes #12197

[louy2]

Not sure how to add test for this one.

[codecov]

Codecov Report

Merging #12201 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master   #12201   +/-   ##
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  Coverage   96.33%   96.33%           
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  Files          95       95           
  Lines        9120     9120           
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  Hits         8786     8786           
  Misses        334      334           

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[papb]

Hello! I see you are a first-time contributor, thank you for taking the time to help Sequelize! I hope to see more PRs from you in the future!

Thanks for catching the fact that cheerio was missing from devDependencies! 🚀 I either deleted it by accident at some point, or never added it 😅

As for your PR, although it does work, I was hoping for something less specific, that would automatically adapt to further documentation changes.

Would you be willing to improve your PR? I suggest something on the lines of:

• Detect every heading with an ID: $('h1,h2,h3,h4,h5').filter('[id]')
• Find duplicate IDs among them
• Replace their IDs with the following rule:

  #original-header --> #original-header
  #original-header --> #original-header-2
  #original-header --> #original-header-3
  

• Also fix nav links (nice catch, I didn't think of that!) - you can assume that the links appear in nav in the same order they do in the page itself. To find the links you might use something like

  $('li[data-ice="manualNav"] a').filter(function() {
    return $(this).prop('href').endsWith(`${fileName}#${headerBeingFixed}`);
  });

Not sure how to add test for this one.

Don't worry about a test, I think it's not necessary in this case, provided we manually check that it works.

[louy2]

Got confused by the mechanics of _.chain but got it working

[louy2]

Also apparently id can only be set with attr.

[sushantdhiman]

LGTM, waiting for @papb

[papb]

Great work @louy2, thank you very much!!