temporarily fixes printWasted abnormality

[jaehunro]

No longer prints wasted time for newly created DOM nodes
any feed back is greatly appreciated

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[tomocchino]

@spicyj or @sebmarkbage, any feedback on this?

See also Jae's awesome blog posts about optimizing React perf here:
http://jaero.space/blog/react-performance-1/
http://jaero.space/blog/react-performance-2/

[sebmarkbage]

The mountComponent call of ReactDOMComponent also gets measured.

https://github.com/facebook/react/blob/master/src/renderers/dom/shared/ReactDOMComponent.js#L512

You could intercept it similarly to this:

https://github.com/facebook/react/blob/master/src/test/ReactDefaultPerf.js#L209

That should let you log the ID of newly mounted DOM nodes without needing to parse the HTML content. That's a bit safer. We're also actively trying to get rid of both IDs in the DOM and generating innerHTML content so that solution would help a lot.

[jaehunro]

I'm not sure if you meant to actually intercept the mounts in the measure function, but I did, and it works for my test cases. Too good to be true?

[sophiebits]

Does it work equally well if you call _recordWrite(rootNodeID, 'mount', 0, [])? If so, I think that's a little cleaner since you don't need to introduce a separate list to track. If not, this way is okay too.

I can merge this if you squash your commits.

[jaehunro]

By utilizing ReactDefaultPerf._recordWrite, it works properly but also displays the 'mount' in printDOM. This could be beneficial because it shows users which exact components are being newly mounted as opposed to setInnerHTML and having to look through args to find child id's in the markup, but the amount of table rows in printDOM could quickly get out of hand especially when considering a multitude of nested components for larger applications. Also, would the fnName be 'mount' necessarily?

[sophiebits]

I agree that that is pretty noisy. Let's keep it how you have it – mind squashing your commits into one?

[jaehunro]

I'm having some trouble squashing my commits because I pulled and merged from upstream (facebook's repo) in between my commits. How should I go about squashing the commits?

pick myOldCommit
pick facebookCommits
pick myNewCommit

[sophiebits]

Try: git rebase -i upstream/master, then change all but the first line to read "squash" instead of "pick". After rebasing you'll need to force-push to your fork.

[sophiebits]

Looks like you figured it out.

[sophiebits]

(Thank you!)