add a JsonInfoCodec class

add a JsonInfoCodec class

This separates the serialization format from the Info objects themselves
and allows us to explore other serialization formats in the future.

BUG=
R=sigmund@google.com

Committed: https://github.com/dart-lang/dart2js_info/commit/a6bdb61f8feaaed9b50c330e72bc035271fb6e0f

[Harry Terkelsen, 2015-10-15 23:13:12]

het@google.com changed reviewers:
+ sigmund@google.com

[Harry Terkelsen, 2015-10-15 23:13:12]

This CL looks a lot bigger than it actually is. A lot of it is just moving the
toJson/jsonparser methods to a different class

[Siggi Cherem (dart-lang), 2015-10-15 23:36:09]

lgtm

https://codereview.chromium.org/1411523003/diff/20001/lib/info.dart
File lib/info.dart (right):

https://codereview.chromium.org/1411523003/diff/20001/lib/info.dart#newcode485
lib/info.dart:485: class RecursiveInfoVisitor extends InfoVisitor<Null> {
should we add <T> to the recursive visitor as well?

https://codereview.chromium.org/1411523003/diff/20001/lib/json_info_codec.dart
File lib/json_info_codec.dart (right):

https://codereview.chromium.org/1411523003/diff/20001/lib/json_info_codec.dar...
lib/json_info_codec.dart:412: class JsonInfoCodec extends Codec<AllInfo, Map> {
What are your thoughts on these alternative naming options:
- InfoJsonCodec
- AllInfoJsonCodec
- Dart2jsInfoJsonCodec

I'm not sure what the right answer is here, but the JsonInfoCodec name has a
very generic feel, so I was wondering if it helps if we swap the order of the
words or if it improves by explicitly calling out that this is dart2js's info.

WDYT?

https://codereview.chromium.org/1411523003/diff/20001/lib/src/measurements.dart
File lib/src/measurements.dart (right):

https://codereview.chromium.org/1411523003/diff/20001/lib/src/measurements.da...
lib/src/measurements.dart:42: const GroupedMetric('functions', const
[reachableFunctions,]);
remove trailing comma (,) here and below.

https://codereview.chromium.org/1411523003/diff/20001/lib/src/measurements.da...
lib/src/measurements.dart:119: 'polymorphic', const [
I would have preferred the old formatting over what dartfmt did here, oh well :(

[Harry Terkelsen, 2015-10-15 23:59:55]

https://codereview.chromium.org/1411523003/diff/20001/lib/info.dart
File lib/info.dart (right):

https://codereview.chromium.org/1411523003/diff/20001/lib/info.dart#newcode485
lib/info.dart:485: class RecursiveInfoVisitor extends InfoVisitor<Null> {
On 2015/10/15 23:36:08, Siggi Cherem (dart-lang) wrote:
> should we add <T> to the recursive visitor as well?

The default implementation won't work for any T because none of the methods know
how to reduce the results of visiting it's children.

https://codereview.chromium.org/1411523003/diff/20001/lib/json_info_codec.dart
File lib/json_info_codec.dart (right):

https://codereview.chromium.org/1411523003/diff/20001/lib/json_info_codec.dar...
lib/json_info_codec.dart:412: class JsonInfoCodec extends Codec<AllInfo, Map> {
On 2015/10/15 23:36:08, Siggi Cherem (dart-lang) wrote:
> What are your thoughts on these alternative naming options:
> - InfoJsonCodec
> - AllInfoJsonCodec
> - Dart2jsInfoJsonCodec
> 
> I'm not sure what the right answer is here, but the JsonInfoCodec name has a
> very generic feel, so I was wondering if it helps if we swap the order of the
> words or if it improves by explicitly calling out that this is dart2js's info.
> 
> WDYT?

I see what you mean, "info" is not a very meaningful term, but I think
AllInfoJsonCodec is the clearest since it puts "AllInfo" first

https://codereview.chromium.org/1411523003/diff/20001/lib/src/measurements.dart
File lib/src/measurements.dart (right):

https://codereview.chromium.org/1411523003/diff/20001/lib/src/measurements.da...
lib/src/measurements.dart:42: const GroupedMetric('functions', const
[reachableFunctions,]);
On 2015/10/15 23:36:08, Siggi Cherem (dart-lang) wrote:
> remove trailing comma (,) here and below.

Done.

https://codereview.chromium.org/1411523003/diff/20001/lib/src/measurements.da...
lib/src/measurements.dart:119: 'polymorphic', const [
On 2015/10/15 23:36:08, Siggi Cherem (dart-lang) wrote:
> I would have preferred the old formatting over what dartfmt did here, oh well
:(

me too

[Harry Terkelsen, 2015-10-16 00:05:45]

https://codereview.chromium.org/1411523003/diff/20001/lib/src/measurements.dart
File lib/src/measurements.dart (right):

https://codereview.chromium.org/1411523003/diff/20001/lib/src/measurements.da...
lib/src/measurements.dart:119: 'polymorphic', const [
On 2015/10/15 23:59:55, Harry Terkelsen wrote:
> On 2015/10/15 23:36:08, Siggi Cherem (dart-lang) wrote:
> > I would have preferred the old formatting over what dartfmt did here, oh
well
> :(
> 
> me too
looks better with the trailing comma removed

[Harry Terkelsen, 2015-10-16 00:05:57]

Committed patchset #3 (id:40001) manually as
a6bdb61f8feaaed9b50c330e72bc035271fb6e0f (presubmit successful).