Symbols serialize to strings when persisted:
model.some_string = :foo
model.save! # "foo" is persisted
This PR updates the immutable string class to serialize symbols to strings to mirror this behavior as ActiveModel::Attribute calls this serialize method to determine the return value for changed_in_place? Prior to this change this code would report that "something" had changed:
comment = Comment.create! # (has a string "something" field)
comment.update_column :something, :anything # persists "anything" to the "something" field of the comments table
comment.something # or comment.attributes
comment.something_change # will be ["anything", "anything"], note these are `to` and `from` values, but are identical
After this PR the comment.something_change will return nil for this situation.
Fixes#36463
```ruby
$ cd activerecord
$ bin/test test/cases/dirty_test.rb:494
... snip ...
DEPRECATED: Use assert_nil if expecting nil from /home/yahonda/git/rails/activerecord/test/cases/dirty_test.rb:494. This will fail in Minitest 6.
DEPRECATED: Use assert_nil if expecting nil from /home/yahonda/git/rails/activerecord/test/cases/dirty_test.rb:511. This will fail in Minitest 6.
.
Finished in 0.061593s, 16.2356 runs/s, 795.5428 assertions/s.
1 runs, 49 assertions, 0 failures, 0 errors, 0 skips
$
```
Refer seattlerb/minitest#666rails/rails#27712
Incrementing the lock version invalidates any other process's optimistic
lock, which is the desired outcome: the record no longer looks the same
as it did when they loaded it.
`test_update_does_not_run_sql_if_record_has_not_changed` would pass
without #18501 since `assert_queries` ignores BEGIN/COMMIT unless
`ignore_none: true` is given.
Since #32647, empty BEGIN/COMMIT is ommited. So we no longer need to use
`assert_queries(0)` to ignore BEGIN/COMMIT in the queries.
`changes_applied` should be called before continuing around callback
chain. Otherwise the mutation tracker returns old value for methods like
`changed`? or `id_in_database` in around callbacks. Also methods depend
on `id_in_database`, like `update_column`, are not working in
`around_create` callbacks.
```
class Foo < ActiveRecord::Base
around_create :around_create_callback
def around_create_callback
...
yield
p id_in_database # => nil
update_column(:generated_column, generate_value) # silently fails
end
...
end
```
When an array of hashes is added to a `HashWithIndifferentAccess`, the
hashes are replaced with HWIAs by mutating the array in place.
If an attribute's value is an array of hashes, `changes_to_save` will
convert it to an array of HWIAs as a side-effect of adding it to the
changes hash.
Using `merge!` instead of `[]=` fixes the problem, as `merge!` copies
any array values in the provided hash instead of mutating them.
Currently the place where we limit what gets sent to the database is in
the implementation for `partial_writes`. We should also be restricting
it to column names when partial writes are turned off.
Note that we're using `&` instead of just defaulting to
`self.class.column_names`, as the instance version of `attribute_names`
does not include attributes which are uninitialized (were not included
in the select clause)
We already have a _read_attribute method that can get the value we need
from the model. Lets define that method in AM::Dirty and use the
existing one from AR::Dirty rather than introducing a new method.
`supports_migrations?` was added at 4160b518 to determine if schema
statements (`create_table`, `drop_table`, etc) are implemented in the
adapter. But all tested databases has been supported migrations since
a4fc93c3 at least.
This was never really intended to work (at least not without calling
`define_attribute_methods`, which is less common with Active Record). As
we move forward the intention is to require the use of `attribute` over
`attr_accessor` for more complex model behavior both on Active Record
and Active Model, so this behavior is deprecated.
Fixes#27956.
Close#27963.
[Alex Serban & Sean Griffin]
We pretty frequently get bug reports that "dirty is broken inside of
after callbacks". Intuitively they are correct. You'd expect
`Model.after_save { puts changed? }; model.save` to do the same thing as
`model.save; puts model.changed?`, but it does not.
However, changing this goes much farther than just making the behavior
more intuitive. There are a _ton_ of places inside of AR that can be
drastically simplified with this change. Specifically, autosave
associations, timestamps, touch, counter cache, and just about anything
else in AR that works with callbacks have code to try to avoid "double
save" bugs which we will be able to flat out remove with this change.
We introduce two new sets of methods, both with names that are meant to
be more explicit than dirty. The first set maintains the old behavior,
and their names are meant to center that they are about changes that
occurred during the save that just happened. They are equivalent to
`previous_changes` when called outside of after callbacks, or once the
deprecation cycle moves.
The second set is the new behavior. Their names imply that they are
talking about changes from the database representation. The fact that
this is what we really care about became clear when looking at
`BelongsTo.touch_record` when tests were failing. I'm unsure that this
set of methods should be in the public API. Outside of after callbacks,
they are equivalent to the existing methods on dirty.
Dirty itself is not deprecated, nor are the methods inside of it. They
will only emit the warning when called inside of after callbacks. The
scope of this breakage is pretty large, but the migration path is
simple. Given how much this can improve our codebase, and considering
that it makes our API more intuitive, I think it's worth doing.
assert [1, 3].includes?(2) fails with unhelpful "Asserting failed" message
assert_includes [1, 3], 2 fails with "Expected [1, 3] to include 2" which makes it easier to debug and more obvious what went wrong
As part of refactoring mutation detection to be more performant, we
introduced the concept of `original_value` to `Attribute`. This was not
overridden in `Attribute::Uninitialized` however, so assigning ot an
uninitialized value and calling `.changed?` would raise
`NotImplementedError`.
We are using a sentinel value rather than checking the result of
`original_attribute.initialized?` in `changed?` because `original_value`
might go through more than one node in the tree.
Fixes#25228
This was passing prior to 20b177b78ef5d21c8cc255f0376f6b2e948de234,
because we were not properly applying our contract that
`model.attr == model.tap(&:save).reload.attr` for this case. Now that
that has been resolved, this test is invalid on some adapters
When I originally reviewed the #20317, I believe these changes were
present, but it appears that it was later updated so that they were
removed. Since Travis hadn't re-run the build, this slipped through.
If a getter has side effects on the DB, `changes_applied` will be called
twice. The second time will try and remove the changed attributes cache,
and will crash because it's already been unset. This also demonstrates
that we shouldn't assume that calling getters won't change the value of
`changed_attributes`, and we need to clear the cache if an attribute is
modified.
Fixes#20531.
This is a usability change to fix a quirk from our definition of partial
writes. By default, we only persist changed attributes. When creating a
new record, this is assumed that the default values came from the
database. However, if the user provided a default, it will not be
persisted, since we didn't see it as "changed". Since this is a very
specific case, I wanted to isolate it with the other quirks that come
from user provided default values. The number of edge cases which are
presenting themselves are starting to make me wonder if we should just
remove the ability to assign a default, in favor of overriding
`initialize`. For the time being, this is required for the attributes
API to not have confusing behavior.
We had to delete one test, since this actually changes the meaning of
`.changed?` on Active Record models. It now specifically means
`changed_from_database?`. While I think this will make the attributes
API more ergonomic to use, it is a subtle change in definition (though
not a backwards incompatible one). We should probably figure out the
right place to document this. (Feel free to open a PR doing that if
you're reading this).
/cc @rafaelfranca @kirs @senny
This is an alternate implementation of #19921.
Close#19921.
[Sean Griffin & Kir Shatrov]
This helper no longer makes sense as a separate method. Instead I'll
just have `deserialize` call `cast` by default. This led to a random
infinite loop in the `JSON` pg type, when it called `super` from
`deserialize`. Not really a great way to fix that other than not calling
super, or continuing to have the separate method, which makes the public
API differ from what we say it is.