DevTools: more previews when formatting logged arrays/objects

DevTools: more previews when formatting logged arrays/objects

BUG=607681, 607682

[luoe, 2016-06-13 23:33:51]

luoe@chromium.org changed reviewers:
+ dgozman@chromium.org, kozyatinskiy@chromium.org

[luoe, 2016-06-13 23:33:52]

Hi, I'm uploading this CL for review, even though I'm still working on the
tests.  Soliciting feedback on both code style as well as requesting you to try
out the functionality, as I'm sure I missed some edge cases.

Things it doesn't currently handle:
- logging a long array won't show its length in collapsed form
- Maps, Sets don't show their size
- color/style changes on their way

Thanks!

[dgozman, 2016-06-14 09:08:30]

What a patch! I feel that it's too big to understand. Can we break it up into
smaller improvements?
It would be even better to have a doc which describes what we do now vs what we
want, with details like formatting arrays vs objects vs primitives, different
wrapping techniques we use, etc. Otherwise it's very hard to assess the impact
of such a change.

https://codereview.chromium.org/2012033002/diff/40001/third_party/WebKit/Sour...
File third_party/WebKit/Source/platform/v8_inspector/InjectedScriptSource.js
(right):

https://codereview.chromium.org/2012033002/diff/40001/third_party/WebKit/Sour...
third_party/WebKit/Source/platform/v8_inspector/InjectedScriptSource.js:350:
generatePreview = descriptor.name !== "__proto__";
I don't get this change.

[luoe, 2016-06-14 17:49:29]

Yes... I can break out the patch into a few CLs:
- TreeElements in a TreeOutline can display alternate valueElements when
expanded
- Make every object/array/function expandable with an arrow
- Show more previews, use character cutoffs in previews (along with a doc)
- Separate CL for tests

https://codereview.chromium.org/2012033002/diff/40001/third_party/WebKit/Sour...
File third_party/WebKit/Source/platform/v8_inspector/InjectedScriptSource.js
(right):

https://codereview.chromium.org/2012033002/diff/40001/third_party/WebKit/Sour...
third_party/WebKit/Source/platform/v8_inspector/InjectedScriptSource.js:350:
generatePreview = descriptor.name !== "__proto__";
On 2016/06/14 09:08:30, dgozman_slow wrote:
> I don't get this change.

In another place, I changed a call to getProperties to use generatePreview =
true.  The intent of this line is to never generate a preview for the __proto__,
since it looks strange, especially when not expecting it.

I'll make a note to describe this in the doc.

[luoe, 2016-06-24 23:06:04]

Description was changed from

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DevTools: more previews when formatting logged arrays/objects

BUG=607681, 607682
==========

to

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DevTools: more previews when formatting logged arrays/objects

BUG=607681, 607682
==========