Nodoc validate_index_length! method

 Added documentation for PostGreSQL database_statements [ci skip]

 - This method is used only by adapters to validate length of new index names.

 - Added documentation for index_name_exists? and rename_index.
 - Also changed rails to \Rails in documentation of
   allowed_index_name_length.

Fix style/grammar/typos in Caching guide.

* avoid using unnecessary commas
* fix some typos

Document :tld_length option for cookies.

Add missing error messages for sucker_punch, sneakers and qu

fix error message

change raise to use rails conventions

fix misspells

CHANGELOG punctuation fix

This reverts commit 00aa1afa, reversing
changes made to b584cc68.

Reason:

As far as we can tell, this should not be the case. Both localhost, 127.0.0.1
and ::1 is "supposed to work", so this is probably a bug somewhere.

Reopening #19815 instead.

Punctuation fix

[ci skip] Correct grammar, add docs to ActiveRecord migration generator

Make ActionMailer #cache helper a no-op, not an exception

Remove use of mocha in the named base tests

Rewording

Rewording in accordance with the documentation guidelines (‘Prefer
wordings that avoid "you"s and "your”s.’) and to remove in particular
“if you'd call”.

Previews when `mail` wasn't called (NullMail instances).

While this was true before when every `dd` had a value,
this patch makes sure that everything keeps lining up even
when the `dd` node is blank.

Make sure you execute rake rdoc from rails root directory [ci skip]

1. Make clear where rake rdoc is executed
2. Make clear where the generated HTML files for the guides are stored
3. Use bundler 1.3.5 or later

Clarify test_order default configuration behaviour [ci skip]

Fixed typo in documentation

 Added note about non-GET links getting converted to GET links in mailer  Added note about non-GET links getting converted to GET links in mailer templates [ci skip]

AUTH PLAIN is Base64 encoded [ci skip]

Explain config.active_support.test_order defaults
to :random in newly-generated applications thanks
to generated config/environments/test.rb, otherwise
default is :sorted (until Rails 5.0).

Rails has different naming conventions for the inverse assertion
methods. While minitest uses `refute` we use `_not`. We should have a
table listing the common assertions that you want to use in the Rails
context.

Refs #18305.

Unlock sneakers adapter version