fix #30462, update function_type tests to understand covariant generics

fix #30462, update function_type tests to understand covariant generics

In particular, the reified type of method tear-offs may substitute Object for the class type parameter. This is done when the parameter needs a covariance check. The test generator is updated to understand this distinction.

R=floitsch@google.com

Committed: https://github.com/dart-lang/sdk/commit/2ea6a5dd5cd389db00479ea41c74241ff8336ea4

[Jennifer Messerly, 2017-08-17 06:40:04]

Description was changed from

==========
fix #30462, update function_type tests to understand covariant generics
==========

to

==========
fix #30462, update function_type tests to understand covariant generics

In particular, the reified type of method tear-offs may substitute Object for
the class type parameter. This is done when the parameter needs a covariance
check. The test generator is updated to understand this distinction.
==========

[Jennifer Messerly, 2017-08-17 06:40:04]

jmesserly@google.com changed reviewers:
+ floitsch@google.com, leafp@google.com

[floitsch, 2017-08-17 07:48:45]

Good catch. Thanks for fixing the generator.

LGTM.

https://codereview.chromium.org/3002773002/diff/20001/tests/language_2/functi...
File tests/language_2/function_type/test_generator.dart (right):

https://codereview.chromium.org/3002773002/diff/20001/tests/language_2/functi...
tests/language_2/function_type/test_generator.dart:316: .any((l) => l?.any((p)
=> p.takesT) == true);
use ?? false.

This makes it clear, that you have to worry about `null`.

https://codereview.chromium.org/3002773002/diff/20001/tests/language_2/functi...
tests/language_2/function_type/test_generator.dart:322: .any((l) => l?.any((p)
=> p.returnsT) == true);
ditto.

https://codereview.chromium.org/3002773002/diff/20001/tests/language_2/functi...
tests/language_2/function_type/test_generator.dart:326: return returnType?.usesT
== true || returnsT;
return returnType?.usesT ?? returnsT;

https://codereview.chromium.org/3002773002/diff/20001/tests/language_2/functi...
tests/language_2/function_type/test_generator.dart:369: bool get returnsT =>
name == "T" || generic?.any((t) => t.returnsT) == true;
ditto.

https://codereview.chromium.org/3002773002/diff/20001/tests/language_2/functi...
tests/language_2/function_type/test_generator.dart:371: bool get takesT =>
generic?.any((t) => t.takesT) == true;
ditto.

[Jennifer Messerly, 2017-08-17 20:00:41]

Description was changed from

==========
fix #30462, update function_type tests to understand covariant generics

In particular, the reified type of method tear-offs may substitute Object for
the class type parameter. This is done when the parameter needs a covariance
check. The test generator is updated to understand this distinction.
==========

to

==========
fix #30462, update function_type tests to understand covariant generics

In particular, the reified type of method tear-offs may substitute Object for
the class type parameter. This is done when the parameter needs a covariance
check. The test generator is updated to understand this distinction.

R=floitsch@google.com

Committed:
https://github.com/dart-lang/sdk/commit/2ea6a5dd5cd389db00479ea41c74241ff8336ea4
==========

[Jennifer Messerly, 2017-08-17 20:00:43]

Committed patchset #3 (id:40001) manually as
2ea6a5dd5cd389db00479ea41c74241ff8336ea4 (presubmit successful).

[Jennifer Messerly, 2017-08-17 23:44:20]

(oops, forgot to hit send on my comments)

https://codereview.chromium.org/3002773002/diff/20001/tests/language_2/functi...
File tests/language_2/function_type/test_generator.dart (right):

https://codereview.chromium.org/3002773002/diff/20001/tests/language_2/functi...
tests/language_2/function_type/test_generator.dart:309: return returnType?.usesT
== true ||
fixed this too (per comment below)

https://codereview.chromium.org/3002773002/diff/20001/tests/language_2/functi...
tests/language_2/function_type/test_generator.dart:316: .any((l) => l?.any((p)
=> p.takesT) == true);
On 2017/08/17 07:48:44, floitsch wrote:
> use ?? false.
> 
> This makes it clear, that you have to worry about `null`.

Oh nice! I was trying to match the style of `get usesT` above, but I really like
this suggestion. I'll fix all of them to be consistent with ?? false style.

https://codereview.chromium.org/3002773002/diff/20001/tests/language_2/functi...
tests/language_2/function_type/test_generator.dart:322: .any((l) => l?.any((p)
=> p.returnsT) == true);
On 2017/08/17 07:48:45, floitsch wrote:
> ditto.

Done.

https://codereview.chromium.org/3002773002/diff/20001/tests/language_2/functi...
tests/language_2/function_type/test_generator.dart:326: return returnType?.usesT
== true || returnsT;
On 2017/08/17 07:48:45, floitsch wrote:
> return returnType?.usesT ?? returnsT;

Done.

https://codereview.chromium.org/3002773002/diff/20001/tests/language_2/functi...
tests/language_2/function_type/test_generator.dart:369: bool get returnsT =>
name == "T" || generic?.any((t) => t.returnsT) == true;
On 2017/08/17 07:48:44, floitsch wrote:
> ditto.

Done.

https://codereview.chromium.org/3002773002/diff/20001/tests/language_2/functi...
tests/language_2/function_type/test_generator.dart:371: bool get takesT =>
generic?.any((t) => t.takesT) == true;
On 2017/08/17 07:48:45, floitsch wrote:
> ditto.

Done.