1252182 - Dragging selected text to new place fails and causes cursor blinking

Status: RESOLVED FIXED

(DevTools :: Source Editor, defect, P2)

Description

[arni2033]

>>>   My Info:   Win7_64, Nightly 47, 32bit, ID 20160229030448
STR:
1.A) Open Scratchpad (Shift+F4)
1.B) Open new tab. Open new tab. Open Style editor (Shift+F7)
2. Select several symbols (<= 10 symbols)
3. Hover mouse over the selected text
4. Hold left mouse button
5. Move mouse pointer between any 2 consequent non-selected symbols
6. Hover mouse over the caret (or 1-3px to the left from the caret)
7. Wait 3 seconds (only to see the result), then release left mouse button

AR:
 After Step 6 cursor started to blink.
 After Step 7 nothing happens (text stays on it's old place)

ER:
 After step 6 there should be no blinking.
 After Step 7 selected text should be moved from old place to the new place,
              i.e. between 2 letters from Step 5.

Screencast:
(On my screencast, cursor is invisible when it's in "cursor:text" state. Sorry)
> https://dl.dropboxusercontent.com/s/6ot2grx3s4rtbeb/screencast%201%20-%20Dragging%20selected%20text%20to%20new%20place%20fails%20and%20causes%20cursor%20blinking.webm?dl=0

This is regression from bug 1132557. Regression range:
> https://hg.mozilla.org/integration/fx-team/pushloghtml?fromchange=21015383ac41061eab25d01b546cd2713ff17b36&tochange=2bfe5435c1d1e2784af3b225d629a210023daecd

Comment 1

[J. Ryan Stinnett [:jryans] (Use needinfo, replies may be slow)]

:gl, can you assess priority here since this is fall out from a CM upgrade?

Comment 2

[Gabriel Luong [:gl] (ΦωΦ)]

This seems to be affecting CodeMirror upstream. I will file a bug with them and go from there.

Comment 3

[Brian Grinstead [:bgrins]]

Gabe, can you please add a link to the issue with CM when you file it?

Comment 4

[Gabriel Luong [:gl] (ΦωΦ)]

So, I was testing the latest CodeMirror 5.15.2, and it might be fixed upstream. I was still able to reproduce the bug in 5.14.2 (our current CM in tree). Awaiting any comments in https://github.com/codemirror/CodeMirror/issues/4040, but I will try upgrading our CodeMirror and test locally.

Comment 5

[Ritu Kothari (:ritu) (Inactive, please n-i to RyanVM, jcristau, or pascal)]

Given that this is a regression since Fx44, it is not a release blocker and a wontfix for 47 now. I hope we are able to fix it in time for Fx48/49 release.

Comment 6

[Gabriel Luong [:gl] (ΦωΦ)]

This was resolved in the latest upgrade to CodeMirror 5.16.0 in Bug 1282287. This bug was solved in https://github.com/codemirror/CodeMirror/issues/4040.

Comment 7

[Liz Henry (:lizzard) (relman/hg->git project)]

Looks like we brought this fix to 50 in bug 1282287. It is a bit late at this point to take the change in beta since we are heading into beta 8 today.