Support checking of malbounded types.

Support checking of malbounded types.

BUG=
R=karlklose@google.com

Committed: https://code.google.com/p/dart/source/detail?r=29531

[karlklose, 2013-10-30 09:47:43]

LGTM, with a few comments about names.

https://codereview.chromium.org/48383003/diff/1/sdk/lib/_internal/compiler/im...
File sdk/lib/_internal/compiler/implementation/dart_types.dart (right):

https://codereview.chromium.org/48383003/diff/1/sdk/lib/_internal/compiler/im...
sdk/lib/_internal/compiler/implementation/dart_types.dart:1267: int
isMaybeSubtype(DartType t, DartType s) {
The name indicates that this is a predicate. How about 'computeSubtypeRelation'?

https://codereview.chromium.org/48383003/diff/1/sdk/lib/_internal/compiler/im...
sdk/lib/_internal/compiler/implementation/dart_types.dart:1298: }
assert that both links are empty.

https://codereview.chromium.org/48383003/diff/1/sdk/lib/_internal/compiler/im...
File sdk/lib/_internal/compiler/implementation/ssa/builder.dart (right):

https://codereview.chromium.org/48383003/diff/1/sdk/lib/_internal/compiler/im...
sdk/lib/_internal/compiler/implementation/ssa/builder.dart:3730: bool
staticError = false;
How about 'definitelyFails'?

https://codereview.chromium.org/48383003/diff/1/sdk/lib/_internal/compiler/im...
sdk/lib/_internal/compiler/implementation/ssa/builder.dart:3738: int
maybeSubtype = compiler.types.isMaybeSubtype(typeArgument, bound);
'maybeSubtype' -> 'subtypeRelation'?

https://codereview.chromium.org/48383003/diff/1/sdk/lib/_internal/compiler/im...
sdk/lib/_internal/compiler/implementation/ssa/builder.dart:3741: String message;
You can merge the two branches like this:

String message =
 "Can't create an instance of malbounded type '$type': "
 "'${typeArgument}' is not a subtype of bound '${bound}' for "
 "type variable '${typeVariable}' of type "
 "'${instance.element.thisType}'${type == instance ? " on the supertype
'${instance}' of '${type}'${}" : ""}.";

or with an explicit if-else that modifies message.

https://codereview.chromium.org/48383003/diff/1/sdk/lib/_internal/lib/js_rti....
File sdk/lib/_internal/lib/js_rti.dart (right):

https://codereview.chromium.org/48383003/diff/1/sdk/lib/_internal/lib/js_rti....
sdk/lib/_internal/lib/js_rti.dart:291: assertIsSubtype(var subtype, var
supertype, String message) {
It is a bit unfortunate that this name is so similar to assertSubtype, which
tests something completely different.

https://codereview.chromium.org/48383003/diff/1/tests/language/language_dart2...
File tests/language/language_dart2js.status (right):

https://codereview.chromium.org/48383003/diff/1/tests/language/language_dart2...
tests/language/language_dart2js.status:37: type_variable_bounds2_test/01: Fail #
Issue 12702
Why are these two failing now?

[Johnni Winther, 2013-10-30 11:19:42]

https://codereview.chromium.org/48383003/diff/1/sdk/lib/_internal/compiler/im...
File sdk/lib/_internal/compiler/implementation/dart_types.dart (right):

https://codereview.chromium.org/48383003/diff/1/sdk/lib/_internal/compiler/im...
sdk/lib/_internal/compiler/implementation/dart_types.dart:1267: int
isMaybeSubtype(DartType t, DartType s) {
On 2013/10/30 09:47:43, karlklose wrote:
> The name indicates that this is a predicate. How about
'computeSubtypeRelation'?

Done.

https://codereview.chromium.org/48383003/diff/1/sdk/lib/_internal/compiler/im...
sdk/lib/_internal/compiler/implementation/dart_types.dart:1298: }
On 2013/10/30 09:47:43, karlklose wrote:
> assert that both links are empty.

Done.

https://codereview.chromium.org/48383003/diff/1/sdk/lib/_internal/compiler/im...
File sdk/lib/_internal/compiler/implementation/ssa/builder.dart (right):

https://codereview.chromium.org/48383003/diff/1/sdk/lib/_internal/compiler/im...
sdk/lib/_internal/compiler/implementation/ssa/builder.dart:3730: bool
staticError = false;
On 2013/10/30 09:47:43, karlklose wrote:
> How about 'definitelyFails'?

Done.

https://codereview.chromium.org/48383003/diff/1/sdk/lib/_internal/compiler/im...
sdk/lib/_internal/compiler/implementation/ssa/builder.dart:3738: int
maybeSubtype = compiler.types.isMaybeSubtype(typeArgument, bound);
On 2013/10/30 09:47:43, karlklose wrote:
> 'maybeSubtype' -> 'subtypeRelation'?

Done.

https://codereview.chromium.org/48383003/diff/1/sdk/lib/_internal/compiler/im...
sdk/lib/_internal/compiler/implementation/ssa/builder.dart:3741: String message;
On 2013/10/30 09:47:43, karlklose wrote:
> You can merge the two branches like this:
> 
> String message =
>  "Can't create an instance of malbounded type '$type': "
>  "'${typeArgument}' is not a subtype of bound '${bound}' for "
>  "type variable '${typeVariable}' of type "
>  "'${instance.element.thisType}'${type == instance ? " on the supertype
> '${instance}' of '${type}'${}" : ""}.";
> 
> or with an explicit if-else that modifies message.

Done.

https://codereview.chromium.org/48383003/diff/1/tests/language/language_dart2...
File tests/language/language_dart2js.status (right):

https://codereview.chromium.org/48383003/diff/1/tests/language/language_dart2...
tests/language/language_dart2js.status:37: type_variable_bounds2_test/01: Fail #
Issue 12702
On 2013/10/30 09:47:43, karlklose wrote:
> Why are these two failing now?

type_variable_bounds_test/02: We don't check malboundedness on 
assignment.
type_variable_bounds2_test/01: We check malboundness fully on instantiation.
type_variable_bounds2_test/04: We don't check malboundedness on is-tests.
type_variable_bounds2_test/06: Intended to fail at assignment but we fail at
instantiation.
type_variable_bounds3_test/00: We don't check malboundedness on is-tests.

[Johnni Winther, 2013-10-30 11:27:44]

Committed patchset #2 manually as r29531 (presubmit successful).