Bundle Bootstrap Icons (Sass + web fonts)

CHANGELOG.md

@@ -6,6 +6,13 @@ The changelog only includes changes specific to the RubyGem.
 The Bootstrap framework changes can be found in [the Releases section of twbs/bootstrap](https://github.com/twbs/bootstrap/releases).
 Release announcement posts on [the official Bootstrap blog](http://blog.getbootstrap.com) contain summaries of the most noteworthy changes made in each release of Bootstrap.
 
+# Unreleased
+
+* Bundle [Bootstrap Icons](https://icons.getbootstrap.com/) v1.13.1 (Sass + web fonts), opt-in via
+  `@import "bootstrap-icons-sprockets"` (Sprockets), `@import "bootstrap-icons-propshaft"`
+  (Propshaft), or `@import "bootstrap-icons"`.
+  [#276](https://github.com/twbs/bootstrap-rubygem/issues/276)
+
 # 5.3.4
 
 * Autoprefixer is now optional.

README.md

@@ -105,6 +105,38 @@ the concatenated `bootstrap` for faster compilation:
 //= require bootstrap
 ```
 
+#### Bootstrap Icons
+
+The gem also bundles [Bootstrap Icons](https://icons.getbootstrap.com/) (Sass and the icon web fonts),
+so icons can be served from your own app through the asset pipeline instead of a CDN.
+Their use is entirely optional — nothing is included unless you import them.
+
+With Sprockets (`dartsass-sprockets` or `sassc-rails`), import the Sprockets variant,
+which resolves the fonts through the asset pipeline:
+
+```scss
+@import "bootstrap-icons-sprockets";
+```
+
+With Propshaft (`dartsass-rails`), import the Propshaft variant, which emits
+root-relative font URLs that Propshaft rewrites to the digested paths
+(without upstream's `?hash` query string, so the URLs also match
+`preload_link_tag "bootstrap-icons.woff2"` if you preload the font):
+
+```scss
+@import "bootstrap-icons-propshaft";
+```
+
+Otherwise, import `bootstrap-icons` and override
+[`$bootstrap-icons-font-dir` or `$bootstrap-icons-font-src`](assets/stylesheets/_bootstrap-icons.scss)
+to wherever the fonts (in [assets/fonts](assets/fonts)) are served from.
+
+Then use icons as usual:
+
+```html
+<i class="bi bi-alarm"></i>
+```
+
 ### b. Other Ruby frameworks
 
 If your framework uses Sprockets or Hanami,

Rakefile

@@ -77,6 +77,12 @@ task :update, :branch do |t, args|
   Updater.new(branch: args[:branch]).update_bootstrap
 end
 
+desc 'Update Bootstrap Icons from the bootstrap-icons npm package'
+task :update_icons, :version do |t, args|
+  require './tasks/updater/icons'
+  IconsUpdater.new(version: args[:version]).update_icons
+end
+
 desc 'Start a dummy Rails app server'
 task :rails_server do
   require 'rack'

assets/stylesheets/_bootstrap-icons-propshaft.scss

@@ -0,0 +1,12 @@
+// Bootstrap Icons for Propshaft: resolves the icon fonts through the asset pipeline.
+// Import this instead of "bootstrap-icons" when using Propshaft (e.g. with dartsass-rails):
+//
+//     @import "bootstrap-icons-propshaft";
+//
+// The root-relative URLs are logical asset paths that Propshaft rewrites to digested
+// paths. Upstream's "?hash" cache-buster is dropped: Propshaft already fingerprints
+// the filename, and the query string would make the CSS font URL differ from
+// preload_link_tag's URL, causing browsers to download the font twice.
+$bootstrap-icons-font-src: url("/bootstrap-icons.woff2") format("woff2"), url("/bootstrap-icons.woff") format("woff") !default;
+
+@import "bootstrap-icons";

assets/stylesheets/_bootstrap-icons-sprockets.scss

@@ -0,0 +1,7 @@
+// Bootstrap Icons for Sprockets: resolves the icon fonts through the asset pipeline.
+// Import this instead of "bootstrap-icons" when using Sprockets:
+//
+//     @import "bootstrap-icons-sprockets";
+$bootstrap-icons-font-src: font-url("bootstrap-icons.woff2") format("woff2"), font-url("bootstrap-icons.woff") format("woff") !default;
+
+@import "bootstrap-icons";