Add after_bundle to the release notes and upgrade guide

2 files changed, 35 insertions, 0 deletions

diff --git a/guides/source/4_2_release_notes.md b/guides/source/4_2_release_notes.md
index 12db528b91..a39dd9ace0 100644
--- a/guides/source/4_2_release_notes.md
+++ b/guides/source/4_2_release_notes.md
@@ -85,6 +85,9 @@ Please refer to the [Changelog][railties] for detailed changes.
 *   Introduced `Rails.gem_version` as a convenience method to return `Gem::Version.new(Rails.version)`.
     ([Pull Request](https://github.com/rails/rails/pull/14101))
 
+*   Introduced an `after_bundle` callback in the Rails templates.
+    ([Pull Request](https://github.com/rails/rails/pull/16359))
+
 
 Action Pack
 -----------
diff --git a/guides/source/upgrading_ruby_on_rails.md b/guides/source/upgrading_ruby_on_rails.md
index b3e4505fc0..62e4071935 100644
--- a/guides/source/upgrading_ruby_on_rails.md
+++ b/guides/source/upgrading_ruby_on_rails.md
@@ -58,6 +58,38 @@ When assigning `nil` to a serialized attribute, it will be saved to the database
 as `NULL` instead of passing the `nil` value through the coder (e.g. `"null"`
 when using the `JSON` coder).
 
+### `after_bundle` in Rails templates
+
+If you have a Rails template that adds all the files in version control, it
+fails to add the generated binstubs because it gets executed before Bundler:
+
+```ruby
+# template.rb
+generate(:scaffold, "person name:string")
+route "root to: 'people#index'"
+rake("db:migrate")
+
+git :init
+git add: "."
+git commit: %Q{ -m 'Initial commit' }
+```
+
+You can now wrap the `git` calls in an `after_bundle` block. It will be run
+after the binstubs have been generated.
+
+```ruby
+# template.rb
+generate(:scaffold, "person name:string")
+route "root to: 'people#index'"
+rake("db:migrate")
+
+after_bundle do
+  git :init
+  git add: "."
+  git commit: %Q{ -m 'Initial commit' }
+end
+```
+
 Upgrading from Rails 4.0 to Rails 4.1
 -------------------------------------