Update dart2js parser to disallow repeated comparisons and prefix +.

Update dart2js parser to disallow repeated comparisons and prefix +.

Remove support for prefix plus on integer literals.
Remove support for (a < b < c) and (a == b == c) syntax.

BUG= http://dartbug.com/13223
R=ahe@google.com

Committed: https://code.google.com/p/dart/source/detail?r=27692

[Lasse Reichstein Nielsen, 2013-09-18 13:22:25]

I will update expectations if ok'ed.

[Lasse Reichstein Nielsen, 2013-09-18 13:41:18]

https://codereview.chromium.org/23450044/diff/1/sdk/lib/_internal/compiler/im...
File sdk/lib/_internal/compiler/implementation/scanner/parser.dart (left):

https://codereview.chromium.org/23450044/diff/1/sdk/lib/_internal/compiler/im...
sdk/lib/_internal/compiler/implementation/scanner/parser.dart:1642:
allowCascades);
WOuld it be better to keep the 'if' and the last two statements here?

[ahe, 2013-09-18 13:42:59]

https://codereview.chromium.org/23450044/diff/1/sdk/lib/_internal/compiler/im...
File sdk/lib/_internal/compiler/implementation/scanner/parser.dart (left):

https://codereview.chromium.org/23450044/diff/1/sdk/lib/_internal/compiler/im...
sdk/lib/_internal/compiler/implementation/scanner/parser.dart:1642:
allowCascades);
On 2013/09/18 13:41:19, Lasse Reichstein Nielsen wrote:
> WOuld it be better to keep the 'if' and the last two statements here?

Yes. And it would be even better if you replace listener.recoverableError with
listener.reportError.

[Lasse Reichstein Nielsen, 2013-09-19 07:39:05]

Done, PTAL

[ahe, 2013-09-19 09:51:23]

On 2013/09/19 07:39:05, Lasse Reichstein Nielsen wrote:
> Done, PTAL

I think you forgot to upload the patch set.

[Lasse Reichstein Nielsen, 2013-09-19 10:21:50]

Now with actual CL.

[ahe, 2013-09-19 12:04:36]

https://codereview.chromium.org/23450044/diff/8001/sdk/lib/_internal/compiler...
File sdk/lib/_internal/compiler/implementation/scanner/parser.dart (right):

https://codereview.chromium.org/23450044/diff/8001/sdk/lib/_internal/compiler...
sdk/lib/_internal/compiler/implementation/scanner/parser.dart:1633:
listener.reportError("Unexpected token '+'", token: token);
I don't think this works. This is the definition of reportError:

  void reportError(Spannable spannable,
                   MessageKind errorCode,
                   [Map arguments = const {}]) {
...

[Lasse Reichstein Nielsen, 2013-09-20 08:10:35]

Updated, PTAL.

[ahe, 2013-09-20 08:17:16]

LGTM!

https://codereview.chromium.org/23450044/diff/13001/sdk/lib/_internal/compile...
File sdk/lib/_internal/compiler/implementation/warnings.dart (right):

https://codereview.chromium.org/23450044/diff/13001/sdk/lib/_internal/compile...
sdk/lib/_internal/compiler/implementation/warnings.dart:905: 'Error: "+" is not
a prefix operator.');
Could you add an example and "howToFix"?

[Lasse Reichstein Nielsen, 2013-09-20 08:26:15]

https://codereview.chromium.org/23450044/diff/13001/sdk/lib/_internal/compile...
File sdk/lib/_internal/compiler/implementation/warnings.dart (right):

https://codereview.chromium.org/23450044/diff/13001/sdk/lib/_internal/compile...
sdk/lib/_internal/compiler/implementation/warnings.dart:905: 'Error: "+" is not
a prefix operator.');
What would a fix be?
For "+2" it would just be removing the "+". Any other case of using + as a
prefix is some kind of error that is hard to predict.

[ahe, 2013-09-20 08:33:42]

https://codereview.chromium.org/23450044/diff/13001/sdk/lib/_internal/compile...
File sdk/lib/_internal/compiler/implementation/warnings.dart (right):

https://codereview.chromium.org/23450044/diff/13001/sdk/lib/_internal/compile...
sdk/lib/_internal/compiler/implementation/warnings.dart:905: 'Error: "+" is not
a prefix operator.');
On 2013/09/20 08:26:15, Lasse Reichstein Nielsen wrote:
> What would a fix be?
> For "+2" it would just be removing the "+". Any other case of using + as a
> prefix is some kind of error that is hard to predict.

I think something like:

"Try removing '+'."

https://codereview.chromium.org/23450044/diff/13001/sdk/lib/_internal/compile...
sdk/lib/_internal/compiler/implementation/warnings.dart:905: 'Error: "+" is not
a prefix operator.');
Another thing, please use double quotes for the complete message and single
quotes for substrings. The logic is that Google ignores single quotes in
searches.

[Lasse Reichstein Nielsen, 2013-09-20 08:59:50]

Committed patchset #4 manually as r27692 (presubmit successful).