This commit fixes reported issue #7630 in which counter
caches were not being updated properly when replacing
has_many_through relationships

This reverts commit abf8de85.
We should take a deeper look to those cases flat_map doesn't do deep
flattening.

irb(main):002:0> [[[1,3], [1,2]]].map{|i| i}.flatten
=> [1, 3, 1, 2]
irb(main):003:0> [[[1,3], [1,2]]].flat_map{|i| i}
=> [[1, 3], [1, 2]]

Patches `CollectionAssociation#count` to return 0 without querying
if the parent record is new. Consider the following code:

    class Account
      has_many :dossiers
    end

    class Dossier
      belongs_to :account
    end

    a = Account.new
    a.dossiers.build

    # before patch
    a.dossiers.count
    # SELECT COUNT(*) FROM "dossiers" WHERE "dossiers"."account_id" IS NULL
    # => 0

    # after
    a.dosiers.count # fires without sql query
    # => 0

Fixes #1856.

If assigning to a has_many :through collection against an unsaved
object using the collection=[<array_of_items>] syntax, the join models
were not properly created, previously.

Previously it returned an Array.

If you want an array, call e.g. `Post.to_a` rather than `Post.all`. This
is more explicit.

In most cases this should not break existing code, since
Relations use method_missing to delegate unknown methods to #to_a
anyway.

Closes #1190

interpolation is no longer a thing separate from "normal" assoc
conditions.

Add tests to test that through associations are not readonly, and we can update the records we retrive from the association

:strict

another value has been specified).

See the CHANGELOG for details.

Fixes #950.

This reverts commit c99d507f.

when fetching ids for a collection, bypass preloading
to avoid the unnecessary performance overhead

If a record is removed from a has_many :through, all of the join records
relating to that record should also be removed from the through
association's target.

(Previously the records were removed in the database, but only one was
removed from the in-memory target array.)

Fixes #3425.

Fixes creating records in a through association with a polymorphic source
type.

The join_nodes must be passed to the JoinDependency initializer and therefore counted by the alias tracker. This is because the association_joins are aliased on initialization and then the tables are cached, so it is no use to alias the join_nodes later. Fixes #2556.

when condtions references tables from includes.
Test fail because of invalid sql:
ActiveRecord::StatementInvalid: SQLite3::SQLException: no such column: comments.id:
SELECT "posts".id FROM "posts" INNER JOIN "readers" ON "posts"."id" = "readers"."post_id"
WHERE "readers"."person_id" = 1 AND (comments.id is null)

Bug described in github#925

This commit will revert fix from https://github.com/rails/rails/commit/3436fdfc12d58925e3d981e0afa61084ea34736c , but tests is ok.

Bug described in #6569 ticket.

Refactor Active Record test connection setup. Please see the RUNNING_UNIT_TESTS file for details, but essentially you can now configure things in test/config.yml. You can also run tests directly via the command line, e.g. ruby path/to/test.rb (no rake needed, uses default db connection from test/config.yml). This will help us fix the CI by enabling us to isolate the different Rails versions to different databases.

Signed-off-by: NSantiago Pastorino <santiago@wyeworks.com>

This reverts commit 45c233ef.
Signed-off-by: NSantiago Pastorino <santiago@wyeworks.com>

Signed-off-by: NSantiago Pastorino <santiago@wyeworks.com>