Instantiate parameterized types of type parameters with 'dynamic' type arguments.

Instantiate parameterized types of type parameters with 'dynamic' type arguments.

There is internal code like the added test, which caused us to use
out of scope type parameter during inferred type computation.

Possibly related issues.
https://github.com/dart-lang/sdk/issues/26990
https://github.com/dart-lang/sdk/issues/27072

R=brianwilkerson@google.com, leafp@google.com, paulberry@google.com
BUG=

Committed: https://github.com/dart-lang/sdk/commit/b0d8f475635b4fcfd613aa6090034adcc2a294dc

[scheglov, 2016-09-29 20:14:34]

Description was changed from

==========
Instantiate parameterized types of type parameters with 'dynamic' type
arguments.

There is internal code like the added test, which caused us to use
out of scope type parameter during inferred type computation.

R=brianwilkerson@google.com, paulberry@google.com
BUG=
==========

to

==========
Instantiate parameterized types of type parameters with 'dynamic' type
arguments.

There is internal code like the added test, which caused us to use
out of scope type parameter during inferred type computation.

Possibly related issues.
https://github.com/dart-lang/sdk/issues/26990
https://github.com/dart-lang/sdk/issues/27072

R=brianwilkerson@google.com, paulberry@google.com
BUG=
==========

[Brian Wilkerson, 2016-09-29 20:39:09]

lgtm

https://codereview.chromium.org/2376213003/diff/1/pkg/analyzer/test/src/summa...
File pkg/analyzer/test/src/summary/resynthesize_common.dart (right):

https://codereview.chromium.org/2376213003/diff/1/pkg/analyzer/test/src/summa...
pkg/analyzer/test/src/summary/resynthesize_common.dart:3577:
solo_test_instantiateToBounds_boundRefersToItself() {
Remove "solo_".

[Jennifer Messerly, 2016-09-30 00:22:38]

jmesserly@google.com changed reviewers:
+ jmesserly@google.com

[Jennifer Messerly, 2016-09-30 00:22:39]

oops forgot to hit send earlier. Sorry about that.

https://codereview.chromium.org/2376213003/diff/1/pkg/analyzer/lib/src/dart/e...
File pkg/analyzer/lib/src/dart/element/element.dart (right):

https://codereview.chromium.org/2376213003/diff/1/pkg/analyzer/lib/src/dart/e...
pkg/analyzer/lib/src/dart/element/element.dart:8144: DartType bound =
typeParameters[i].bound ?? DynamicTypeImpl.instance;
there's also resolveToBound on DartType, not sure if that would be helpful

Given how we tend use lazy substitutions I don't usually have a good mental
model of what the difference is between all of these operations :|

https://codereview.chromium.org/2376213003/diff/1/pkg/analyzer/lib/src/dart/e...
pkg/analyzer/lib/src/dart/element/element.dart:8145: return new
TypeSystemImpl().instantiateToBounds(bound);
if we reach this line, we know we're in strongMode right -- because of the "if"
above?

in that case, shouldn't this be StrongTypeSystemImpl?

https://codereview.chromium.org/2376213003/diff/1/pkg/analyzer/test/src/summa...
File pkg/analyzer/test/src/summary/resynthesize_common.dart (right):

https://codereview.chromium.org/2376213003/diff/1/pkg/analyzer/test/src/summa...
pkg/analyzer/test/src/summary/resynthesize_common.dart:3577:
solo_test_instantiateToBounds_boundRefersToItself() {
remove "solo_"?

[scheglov, 2016-09-30 03:42:39]

PTAL

https://codereview.chromium.org/2376213003/diff/1/pkg/analyzer/lib/src/dart/e...
File pkg/analyzer/lib/src/dart/element/element.dart (right):

https://codereview.chromium.org/2376213003/diff/1/pkg/analyzer/lib/src/dart/e...
pkg/analyzer/lib/src/dart/element/element.dart:8145: return new
TypeSystemImpl().instantiateToBounds(bound);
On 2016/09/30 00:22:38, John Messerly wrote:
> if we reach this line, we know we're in strongMode right -- because of the
"if"
> above?
> 
> in that case, shouldn't this be StrongTypeSystemImpl?

Yes, typeSystem is always StrongTypeSystemImpl in this case.

AFAIK we decided that when type parameter has bound, and the bound is a
parameterized type with type parameters as type arguments, then we consider all
these type parameters if they were all dynamic. Unfortunately
StrongTypeSystemImpl.instantiateToBounds() does not do this - it works only for
types which are not bounds of type parameters.

I added explicit TypeSystem.instantiateToDynamic() and call it now for the
current typeSystem.

[Paul Berry, 2016-09-30 12:07:27]

lgtm

[Brian Wilkerson, 2016-09-30 13:40:20]

lgtm

[Leaf, 2016-09-30 23:44:51]

leafp@google.com changed reviewers:
+ leafp@google.com

[Leaf, 2016-09-30 23:44:52]

https://codereview.chromium.org/2376213003/diff/40001/pkg/analyzer/lib/src/da...
File pkg/analyzer/lib/src/dart/element/element.dart (right):

https://codereview.chromium.org/2376213003/diff/40001/pkg/analyzer/lib/src/da...
pkg/analyzer/lib/src/dart/element/element.dart:8145: return
context.typeSystem.instantiateToDynamic(bound);
I don't think this is really right for strong mode, if I understand this
correctly.  The definition of instantiateToBounds for strong mode doesn't just
replace the variables with dynamic, it instead walks sequentially over the type
parameters computing for the ith bound Bi the default type argument Di as Bi
with dynamic for Ti and Dj for Tj for all j < i.  

I'm unhappy with this definition, and am working with the language team to get a
better solution here, but if the goal is consistency with instantiateToBounds I
think this isn't quite right.

[scheglov, 2016-10-03 16:43:46]

PTAL, now with instantiateToBounds().

[Brian Wilkerson, 2016-10-03 17:27:12]

lgtm

[Paul Berry, 2016-10-03 17:58:44]

lgtm

[Leaf, 2016-10-03 18:01:17]

lgtm

[scheglov, 2016-10-03 18:07:05]

Description was changed from

==========
Instantiate parameterized types of type parameters with 'dynamic' type
arguments.

There is internal code like the added test, which caused us to use
out of scope type parameter during inferred type computation.

Possibly related issues.
https://github.com/dart-lang/sdk/issues/26990
https://github.com/dart-lang/sdk/issues/27072

R=brianwilkerson@google.com, paulberry@google.com
BUG=
==========

to

==========
Instantiate parameterized types of type parameters with 'dynamic' type
arguments.

There is internal code like the added test, which caused us to use
out of scope type parameter during inferred type computation.

Possibly related issues.
https://github.com/dart-lang/sdk/issues/26990
https://github.com/dart-lang/sdk/issues/27072

R=brianwilkerson@google.com, leafp@google.com, paulberry@google.com
BUG=

Committed:
https://github.com/dart-lang/sdk/commit/b0d8f475635b4fcfd613aa6090034adcc2a294dc
==========

[scheglov, 2016-10-03 18:07:06]

Committed patchset #4 (id:60001) manually as
b0d8f475635b4fcfd613aa6090034adcc2a294dc (presubmit successful).