Cleanup loaded features and constants after dependency tests.
Explicit route test class

shows the class that the test must extend in order to have the assert_routing method available
FileHandler should not be called for files outside the root

FileHandler#matches? should return false for files that are outside the
"root" path.
Use include_blank value as option label

Update select_tag to reflect documentation and behave the same as form builder select. If the value of include_blank is not boolean true, use that value as the option label.
Fix Relation.rewhere to work with Range values
If Rails is not defined, check ENV["RAILS_ENV"] and ENV["RACK_ENV"].

This fixes a regression introduced by 6cc03675d30b58e28f585720dad14e947a57ff5b.

ActiveRecord, if used without Rails, always checks the "default_env" environment. This would be OK, except that Sinatra also supports environments,
and it runs with {RACK|RAILS}_ENV=production. This patch adds a fallback to RAILS_ENV and RACK_ENV (and ultimately default_env) if Rails.env doesn't exist.
copy reflection_scopes’s unscoped value when building scope for preloading, fixes #11036
Show the user’s application in the source window and select the correct trace list, closes #17312
Add AS::SecurityUtils.secure_compare for constant time string comparison
Use AS secure_compare in AS::MessageVerifier
Use AS secure_compare for CSRF token comparison
Reword documentation for `uncountable` [ci skip]
Merge branch 'mrgilman-reword-uncountable-documentation'
Raises ArgumentError when try to define a scope without a callable

This changes the actual exception `NoMethodError: undefined method `call'
for #<ActiveRecord::Relation []>` to a `ArgumentError` when try to define
a scope without a callable.
DRY up try/try!
Merge pull request #17369 from rails/secure_compare

Secure compare
Merge pull request #17377 from aripollak/dry-try-bang

DRY up try/try!
AR Migrations Guide#Foreign Keys: fix wrong table

[skip ci]
Merge pull request #17381 from jonatack/patch-8

AR Migrations Guide#Foreign Keys: fix wrong table
Improved try documentation [ci skip]

- better `if` example
- Added chaining example to the try method description
- Documented the `respond_to?` check to the try method description
- Clearer wording to explain that argument error is raised on argument mismatch to responding method, rather than to non-responding method (which is handled without exception by `try`)
- `.any?` is more precise than `! .blank?`
 - Don't need to use `try` on `children` as (for regular associations) they will always be a collection or array that responds to `first`
- Fix typos/grammar