Bootstrap 4: roadmap to first beta

Problem/Motivation

Bootstrap 5 is being implemented, but let's not forget Bootstrap 4 which was the first public ui_suite implementation, so it needs some love.

Tasks for 4.0.0-alpha2

Big cleanup.

General:

• Use CDN instead of asset composer (keep previous method in the doc)
  DONE: 357f23fe887e7c5170e15d56bf5f5db5760cb7bd
• Fix dependencies: ui_patterns:ui_patterns_library instead of ui_patterns:ui_patterns
  DONE: 551238a5493f2938389b3358c4032ef044fcd314
• Update to Bootstrap 4.6: https://blog.getbootstrap.com/2021/01/19/bootstrap-4.6.0/
  DONE: 315b8f91551ffcd566080b7c6d48a26e13ddc74c

Patterns:

• Add Figure from https://getbootstrap.com/docs/4.6/content/figures/
  DONE: 0e402acc1e0a7cd019767c967ab73ecca58e3d4e
• Alert: add heading level settings >> Cancelled because changing the heading level has an impact on the display
• ⚠ Compatibility breaker. list_group: remove non-compliant #active & #disabled properties by splitting list_group & list_group_item
  DONE: 542bde6db1f82f96c549f5c8f487f5f546ed88f3

Patterns, reduce problematic PHP usage:

• ⚠ Compatibility breaker. Carousel: remove _ui_suite_bootstrap_extract_carousel_image hook, split slides field between slides and captions, and don't forget to update the "carousel" example.
  DONE: 25c147c8a214c7ad0929332321728be0ab2816af
• ⚠ Remove deprecated function (drupal_get_path) by refactoring with generic callbacks like what has been done in ui_suite_protocol.theme
  DONE: a516a07662ef9f1d958280ca477ba2bf13b1bad9

Styles:

• Add p-* & m-* styles, because already used for previews and expected by users.
  DONE: 008a9f3feb698491eb576b2ffaaec61611c0d970
• Add text-right previewed_with for spacing_padding_right
  DONE: 552222e74e6249d1a8c819d4fe36474467d7d22e
• Compatiblity breaker Split border & border substractive
  DONE: df39ab32224e58a49961f1960f97d8717f870c6b

Examples:

• ⚠ Remove 0, 1, 2.. string and make explicit when fake keys are used to overpass html_tag limitations.
  DONE: d85262dc519287a24af55bb2e92f0604c4e55ac3
• Update carousel because grid_row component has changed
  DONE: 3dbb3f4e0945c8b9ebabbce82c19c611cceffd40

Tasks for 4.0.0-alpha3

Goal: from 70% to 80% of completion.

Patterns:

• Backport table component from Bootstrap 5 (and its presenter template)
  DONE: 3f521af5326345796ad0503f93a66f97a97c52e1
• Backport progress component from Bootstrap 5 (and its presenter template)
  DONE: 2ea5fb21c438991960dd446ad0f7bc0050b60075
• Backport dropdown component from Bootstrap 5 (and introduce a presenter template for dropbutton-wrapper)
  WIP
• Add spinner component
  DONE: 72d8153282b4953678bb502501a40bce56980afe
• Add toast component
  DONE: 6b2452423ad809ea7ec24684b6266128bcf2a7c6 (but a JS issue)

Styles (after the next release of ui_styles):

• Add option specific previewed_with in color style
  DONE: 07e571f1b6b3844ed4a3b45447881734d562fd70

Examples (after the next alpha release of u_example):

• Remove "Bootstrap" from labels
• Split ui_suite_bootstrap.ui_examples.yml between many files
  DONE: 85c9a7115415ed054d05b1f7ce98c6adf8dd58c0
• Attach libraries to example plugin definitions
  POSTPONED

Tasks for 4.0.0-beta1

Goal: from 80% to 90% of completion.

Styles:

• Add Clearfix, Float, Interactions, Overflow & Sizing

Goal: Big clean up, part 2.

Patterns:

• Move scalar props from fields to settings: button.url, badge.url, media.image_url, list_group_item.url, pagination.current
  >> DONE: 5784d9ccd63a8ddf1cf1e1acf818252672a7ad87
• Move other props from fields to settings, once #3345071: Add links setting type is ready: breadcrumb.items, dropdown.menu, navbar.items and pagination.items

Patterns, reduce problematic PHP usage:

• Move container to page.html.twig
• Pagination: Convert current variable directly in Twig, once #3345071: Add links setting type is ready