Don't include node in downcast error message.

Don't include node in downcast error message.

The error itself has the node's location, and putting it in the
message can be ugly if the relevant node is a particularly long one.

Fixes https://github.com/dart-lang/dev_compiler/issues/377.

R=brianwilkerson@google.com, vsm@google.com

Committed: https://github.com/dart-lang/sdk/commit/60ad9a8585b393aeccbcd41b69c9959f959dfbfc

[Bob Nystrom, 2016-01-22 22:48:10]

rnystrom@google.com changed reviewers:
+ brianwilkerson@google.com, vsm@google.com

[Bob Nystrom, 2016-01-22 22:48:10]

One repro case is:

import 'dart:async';

Future<int> returnsFuture() {
  return new Future.value(null).then((_) {
    return;
  });
}

Before:

[warning] new Future.value(null).then((_) {return;}) (Future<dynamic>) will need
runtime check to cast to type Future<int> (/Users/rnystrom/temp/temp.dart, line
4, col 10)

After:

[warning] Unsound cast from Future<dynamic> to Future<int> requires runtime
check (/Users/rnystrom/temp/temp.dart, line 4, col 10)

[Brian Wilkerson, 2016-01-22 23:12:06]

LGTM

[vsm, 2016-01-22 23:12:13]

On 2016/01/22 22:48:10, Bob Nystrom wrote:
> One repro case is:
> 
> import 'dart:async';
> 
> Future<int> returnsFuture() {
>   return new Future.value(null).then((_) {
>     return;
>   });
> }
> 
> Before:
> 
> [warning] new Future.value(null).then((_) {return;}) (Future<dynamic>) will
need
> runtime check to cast to type Future<int> (/Users/rnystrom/temp/temp.dart,
line
> 4, col 10)
> 
> After:
> 
> [warning] Unsound cast from Future<dynamic> to Future<int> requires runtime
> check (/Users/rnystrom/temp/temp.dart, line 4, col 10)

I like!

While you're here (:-)), flutter folks have asked for messages that also make
sense in the a VM production mode setting where there is no runtime check. 
Perhaps:

[warning] Unsound implicit cast from Future<dynamic> to Future<int>

?

[vsm, 2016-01-22 23:16:40]

On 2016/01/22 23:12:13, vsm wrote:
> On 2016/01/22 22:48:10, Bob Nystrom wrote:
> > One repro case is:
> > 
> > import 'dart:async';
> > 
> > Future<int> returnsFuture() {
> >   return new Future.value(null).then((_) {
> >     return;
> >   });
> > }
> > 
> > Before:
> > 
> > [warning] new Future.value(null).then((_) {return;}) (Future<dynamic>) will
> need
> > runtime check to cast to type Future<int> (/Users/rnystrom/temp/temp.dart,
> line
> > 4, col 10)
> > 
> > After:
> > 
> > [warning] Unsound cast from Future<dynamic> to Future<int> requires runtime
> > check (/Users/rnystrom/temp/temp.dart, line 4, col 10)
> 
> I like!
> 
> While you're here (:-)), flutter folks have asked for messages that also make
> sense in the a VM production mode setting where there is no runtime check. 
> Perhaps:
> 
> [warning] Unsound implicit cast from Future<dynamic> to Future<int>
> 
> ?

hixie's general comment on our messages:

https://github.com/dart-lang/sdk/issues/24565

[Bob Nystrom, 2016-01-22 23:58:41]

> While you're here (:-)), flutter folks have asked for messages that also make
> sense in the a VM production mode setting where there is no runtime check. 

Good point!

> [warning] Unsound implicit cast from Future<dynamic> to Future<int>
> 
> ?

Even better. Done.

[vsm, 2016-01-23 00:32:01]

lgtm!

[Bob Nystrom, 2016-01-23 00:52:39]

Description was changed from

==========
Don't include node in downcast error message.

The error itself has the node's location, and putting it in the
message can be ugly if the relevant node is a particularly long one.

Fixes https://github.com/dart-lang/dev_compiler/issues/377.
==========

to

==========
Don't include node in downcast error message.

The error itself has the node's location, and putting it in the
message can be ugly if the relevant node is a particularly long one.

Fixes https://github.com/dart-lang/dev_compiler/issues/377.

R=brianwilkerson@google.com, vsm@google.com

Committed:
https://github.com/dart-lang/sdk/commit/60ad9a8585b393aeccbcd41b69c9959f959dfbfc
==========

[Bob Nystrom, 2016-01-23 00:52:40]

Committed patchset #2 (id:20001) manually as
60ad9a8585b393aeccbcd41b69c9959f959dfbfc (presubmit successful).