Add test on dart2js static analysis of method type parameters.

Add unit test on dart2js static analysis of method type parameters.

The new test is specifically for `dart2js --generic-method-syntax ..`,
executed programmatically using 'memory_compiler.dart'.
It verifies that each method type variable is treated as if it had
been an alias for `dynamic` (so the static analysis allows almost
all usages of these type variables, silently). Note that this behavior
is unlikely to be available with any other tools, and even `dart2js`
will behave differently when generic methods are implemented fully.
Hence, the new test will only be useful as-is during a transitional
period.

R=johnniwinther@google.com

Committed: https://github.com/dart-lang/sdk/commit/d55adbed81b02a4f59acffdfb4f8dad1b4bc2204

[eernst, 2016-05-02 14:31:38]

eernst@google.com changed reviewers:
+ johnniwinther@google.com

[eernst, 2016-05-02 14:31:39]

This CL adds a test which is only meaningful with `dart2js
--generic-method-syntax ..`. It checks that type variables do have a type during
static analysis, and that it is `dynamic`.

The new test is unusual in that it will become obsolete when a full
implementation of generic methods is available, and it is useless for all other
tools than `dart2js`, but Florian and I agreed that it makes sense to test the
current behavior nevertheless.

[eernst, 2016-05-02 14:35:00]

On 2016/05/02 14:31:39, eernst wrote:
> This CL adds a test which is only meaningful with `dart2js
> --generic-method-syntax ..`. It checks that type variables do have a type
during
> static analysis, and that it is `dynamic`.
> 
> The new test is unusual in that it will become obsolete when a full
> implementation of generic methods is available, and it is useless for all
other
> tools than `dart2js`, but Florian and I agreed that it makes sense to test the
> current behavior nevertheless.

Extra info: The three comments were removed because I was looking at
'generic_functions_test.dart' when I created the new test, and noted that they
are incorrect (they make sense in 'generic_methods_test.dart').

Also, there seems to be no 80 char limit on status files, so I did not try to
avoid long lines in there.

[Johnni Winther, 2016-05-03 09:02:46]

https://codereview.chromium.org/1939053002/diff/1/tests/language/generic_meth...
File tests/language/generic_method_type_usage_test.dart (right):

https://codereview.chromium.org/1939053002/diff/1/tests/language/generic_meth...
tests/language/generic_method_type_usage_test.dart:1: // Copyright (c) 2016, the
Dart project authors.  Please see the AUTHORS file
Make this a unittest, like tests/compiler/dart2js/missing_file_test.dart

[floitsch, 2016-05-03 10:52:46]

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

[floitsch, 2016-05-03 10:52:46]

https://codereview.chromium.org/1939053002/diff/1/tests/language/generic_meth...
File tests/language/generic_method_type_usage_test.dart (right):

https://codereview.chromium.org/1939053002/diff/1/tests/language/generic_meth...
tests/language/generic_method_type_usage_test.dart:1: // Copyright (c) 2016, the
Dart project authors.  Please see the AUTHORS file
On 2016/05/03 09:02:45, Johnni Winther wrote:
> Make this a unittest, like tests/compiler/dart2js/missing_file_test.dart

Alternatively make it such that the flag is passed to the test.
@Johnni: do you prefer the unit-test? I don't think it's necessary.

[Johnni Winther, 2016-05-03 10:56:37]

https://codereview.chromium.org/1939053002/diff/1/tests/language/generic_meth...
File tests/language/generic_method_type_usage_test.dart (right):

https://codereview.chromium.org/1939053002/diff/1/tests/language/generic_meth...
tests/language/generic_method_type_usage_test.dart:1: // Copyright (c) 2016, the
Dart project authors.  Please see the AUTHORS file
On 2016/05/03 10:52:46, floitsch wrote:
> On 2016/05/03 09:02:45, Johnni Winther wrote:
> > Make this a unittest, like tests/compiler/dart2js/missing_file_test.dart
> 
> Alternatively make it such that the flag is passed to the test.
> @Johnni: do you prefer the unit-test? I don't think it's necessary.

Yes. It is a more direct test of the property in question; that dart2js reports
no unresolved warning on type variable usage.

[eernst, 2016-05-04 11:07:39]

tests/language/generic_method_type_usage_test.dart moved to
tests/compiler/dart2js and changed to use 'memory_compiler.dart'. Test runs have
failures, including fundamental stuff like this:

Internal Error: dart:core library does not contain required classes: [String]

Currently digging into that.

https://codereview.chromium.org/1939053002/diff/1/tests/language/generic_meth...
File tests/language/generic_method_type_usage_test.dart (right):

https://codereview.chromium.org/1939053002/diff/1/tests/language/generic_meth...
tests/language/generic_method_type_usage_test.dart:1: // Copyright (c) 2016, the
Dart project authors.  Please see the AUTHORS file
On 2016/05/03 10:56:37, Johnni Winther wrote:
> On 2016/05/03 10:52:46, floitsch wrote:
> > On 2016/05/03 09:02:45, Johnni Winther wrote:
> > > Make this a unittest, like tests/compiler/dart2js/missing_file_test.dart
> > 
> > Alternatively make it such that the flag is passed to the test.
> > @Johnni: do you prefer the unit-test? I don't think it's necessary.
> 
> Yes. It is a more direct test of the property in question; that dart2js
reports
> no unresolved warning on type variable usage.

Done.

[Johnni Winther, 2016-05-04 11:12:58]

lgtm

https://codereview.chromium.org/1939053002/diff/20001/tests/compiler/dart2js/...
File tests/compiler/dart2js/generic_method_type_usage_test.dart (right):

https://codereview.chromium.org/1939053002/diff/20001/tests/compiler/dart2js/...
tests/compiler/dart2js/generic_method_type_usage_test.dart:23: import
"package:expect/expect.dart";
You could remove this import and the use of try and Expect in the test since we
don't run the code, anyway.

[eernst, 2016-05-04 12:15:11]

Review response.

Tests run successfully locally (corelib, language, several others), except
`tools/test.py --checked --mode=release dart2js`, which gets a varying number of
timeouts. Most recent run had only one failure, in 'dart2js_batch_test.dart'.

But in branch 'master', fresh from github, without any trace of this CL, I get
17 test failures on `tools/test.py --checked --report --mode=release dart2js`,
when running two similar commands.

Looks like many tests are very nearly running out of time, so they'll fail as
soon as the host is busy for some reason. And it has nothing to do with this CL.

Can we land in this situation?

https://codereview.chromium.org/1939053002/diff/20001/tests/compiler/dart2js/...
File tests/compiler/dart2js/generic_method_type_usage_test.dart (right):

https://codereview.chromium.org/1939053002/diff/20001/tests/compiler/dart2js/...
tests/compiler/dart2js/generic_method_type_usage_test.dart:23: import
"package:expect/expect.dart";
On 2016/05/04 11:12:58, Johnni Winther wrote:
> You could remove this import and the use of try and Expect in the test since
we
> don't run the code, anyway.

Done.

[Johnni Winther, 2016-05-04 12:53:50]

On 2016/05/04 12:15:11, eernst wrote:
> Review response.
> 
> Tests run successfully locally (corelib, language, several others), except
> `tools/test.py --checked --mode=release dart2js`, which gets a varying number
of
> timeouts. Most recent run had only one failure, in 'dart2js_batch_test.dart'.
> 
> But in branch 'master', fresh from github, without any trace of this CL, I get
> 17 test failures on `tools/test.py --checked --report --mode=release dart2js`,
> when running two similar commands.
> 
> Looks like many tests are very nearly running out of time, so they'll fail as
> soon as the host is busy for some reason. And it has nothing to do with this
CL.
> 
> Can we land in this situation?
> 
Yes

[eernst, 2016-05-04 13:00:48]

Discussed the issue IRL.

Building `dart` 1.17.0-edge.0f0b38dab3320ab4b6cf27ac6ffe18d55c2f295e
(landed Friday afternoon) and retrying
`tools/test.py --checked --report --mode=release dart2js`.

Result:
  With that vm in branch master (fresh): zero failures.
  With that vm with this CL on an older master: zero failures.

It looks like the timeouts are caused by the newer vms, so I'll
land, as recommended in feedback.

[eernst, 2016-05-04 13:16:27]

Description was changed from

==========
Add test on dart2js static analysis of method type parameters.

The new test is specifically for `dart2js --generic-method-syntax ..`.
It verifies that each method type variable is treated as if it had
been an alias for `dynamic` (so the static analysis allows almost
all usages of these type variables, silently). Note that this behavior
is unlikely to be available with any other tools, and even `dart2js`
will behave differently when generic methods are implemented fully.
Hence, the new test will only be useful as-is during a transitional
period. The relevant status files have been adjusted accordingly.
==========

to

==========
Add unit test on dart2js static analysis of method type parameters.

The new test is specifically for `dart2js --generic-method-syntax ..`,
executed programmatically using 'memory_compiler.dart'.
It verifies that each method type variable is treated as if it had
been an alias for `dynamic` (so the static analysis allows almost
all usages of these type variables, silently). Note that this behavior
is unlikely to be available with any other tools, and even `dart2js`
will behave differently when generic methods are implemented fully.
Hence, the new test will only be useful as-is during a transitional
period.
==========

[eernst, 2016-05-04 13:21:26]

Description was changed from

==========
Add unit test on dart2js static analysis of method type parameters.

The new test is specifically for `dart2js --generic-method-syntax ..`,
executed programmatically using 'memory_compiler.dart'.
It verifies that each method type variable is treated as if it had
been an alias for `dynamic` (so the static analysis allows almost
all usages of these type variables, silently). Note that this behavior
is unlikely to be available with any other tools, and even `dart2js`
will behave differently when generic methods are implemented fully.
Hence, the new test will only be useful as-is during a transitional
period.
==========

to

==========
Add unit test on dart2js static analysis of method type parameters.

The new test is specifically for `dart2js --generic-method-syntax ..`,
executed programmatically using 'memory_compiler.dart'.
It verifies that each method type variable is treated as if it had
been an alias for `dynamic` (so the static analysis allows almost
all usages of these type variables, silently). Note that this behavior
is unlikely to be available with any other tools, and even `dart2js`
will behave differently when generic methods are implemented fully.
Hence, the new test will only be useful as-is during a transitional
period.

R=johnniwinther@google.com

Committed:
https://github.com/dart-lang/sdk/commit/d55adbed81b02a4f59acffdfb4f8dad1b4bc2204
==========

[eernst, 2016-05-04 13:21:28]

Committed patchset #3 (id:40001) manually as
d55adbed81b02a4f59acffdfb4f8dad1b4bc2204 (presubmit successful).