Add support for field initialization in objects

Add support for field initialization in objects

Fields declared as T f = E are now initialized to the value
expression E evaluates to.
Fields without initalizer expression are intialized with null.


BUG=
R=dmitryas@google.com

Committed: https://github.com/dart-lang/sdk/commit/23311999680846a9840a30523e8610920e1df066

[zhivkag, 2017-07-26 14:02:06]

zhivkag@google.com changed reviewers:
+ dmitryas@google.com, kmillikin@google.com

[Dmitry Stefantsov, 2017-07-27 09:10:39]

I have a couple of questions.  Please, find them below.

https://codereview.chromium.org/2985883002/diff/20001/pkg/kernel/lib/interpre...
File pkg/kernel/lib/interpreter/interpreter.dart (right):

https://codereview.chromium.org/2985883002/diff/20001/pkg/kernel/lib/interpre...
pkg/kernel/lib/interpreter/interpreter.dart:1000: new
InstanceFieldsA(constructor, new Location(value), ctrEnv, bodyCont);
I think [InstanceFieldsA] here is something different from FieldsA from the
spec?  Is it intentional?

https://codereview.chromium.org/2985883002/diff/20001/pkg/kernel/lib/interpre...
pkg/kernel/lib/interpreter/interpreter.dart:1405: /// A field expression is an
initializer expression for a given field defined when
The line is too long.

[zhivkag, 2017-07-27 10:38:21]

https://codereview.chromium.org/2985883002/diff/20001/pkg/kernel/lib/interpre...
File pkg/kernel/lib/interpreter/interpreter.dart (right):

https://codereview.chromium.org/2985883002/diff/20001/pkg/kernel/lib/interpre...
pkg/kernel/lib/interpreter/interpreter.dart:1000: new
InstanceFieldsA(constructor, new Location(value), ctrEnv, bodyCont);
On 2017/07/27 09:10:39, Dmitry Stefantsov wrote:
> I think [InstanceFieldsA] here is something different from FieldsA from the
> spec?  Is it intentional?

It should be the same thing, except for the step (i.e. call method)*.
But you have a good point, I notice that in the specification we use directly
the initializer list. We would need to close over the class of the current
constructor being run too, to know which non-initialized fieds need to be
initialized to null eventually. 
This is why I would prefer to close over the target constructor instead. I
updated the specification.

*The call method is different because we don't have support for initializer list
here yet, which is in a followup CL.

https://codereview.chromium.org/2985883002/diff/20001/pkg/kernel/lib/interpre...
pkg/kernel/lib/interpreter/interpreter.dart:1405: /// A field expression is an
initializer expression for a given field defined when
On 2017/07/27 09:10:39, Dmitry Stefantsov wrote:
> The line is too long.

Done.

[Dmitry Stefantsov, 2017-07-27 10:43:31]

LGTM

https://codereview.chromium.org/2985883002/diff/20001/pkg/kernel/lib/interpre...
File pkg/kernel/lib/interpreter/interpreter.dart (right):

https://codereview.chromium.org/2985883002/diff/20001/pkg/kernel/lib/interpre...
pkg/kernel/lib/interpreter/interpreter.dart:1000: new
InstanceFieldsA(constructor, new Location(value), ctrEnv, bodyCont);
On 2017/07/27 10:38:21, zhivkag wrote:
> On 2017/07/27 09:10:39, Dmitry Stefantsov wrote:
> > I think [InstanceFieldsA] here is something different from FieldsA from the
> > spec?  Is it intentional?
> 
> It should be the same thing, except for the step (i.e. call method)*.
> But you have a good point, I notice that in the specification we use directly
> the initializer list. We would need to close over the class of the current
> constructor being run too, to know which non-initialized fieds need to be
> initialized to null eventually. 
> This is why I would prefer to close over the target constructor instead. I
> updated the specification.
> 
> *The call method is different because we don't have support for initializer
list
> here yet, which is in a followup CL.

Thanks for the explanation!

[zhivkag, 2017-07-27 11:47:23]

Description was changed from

==========
Add support for field initialization in objects

Fields declared as T f = E are now initialized to the value
expression E evaluates to.
Fields without initalizer expression are intialized with null.


BUG=
==========

to

==========
Add support for field initialization in objects

Fields declared as T f = E are now initialized to the value
expression E evaluates to.
Fields without initalizer expression are intialized with null.


BUG=
R=dmitryas@google.com

Committed:
https://github.com/dart-lang/sdk/commit/23311999680846a9840a30523e8610920e1df066
==========

[zhivkag, 2017-07-27 11:47:25]

Committed patchset #3 (id:40001) manually as
23311999680846a9840a30523e8610920e1df066 (presubmit successful).