1582732 - The grid-inspector should update its cached list of LayoutFront instances when targets are added or removed

Status: RESOLVED DUPLICATE of bug 1707884

(DevTools :: Inspector: Layout, defect, P2)

Description

[Patrick Brosset <:pbro>]

In bug 1568857 we made it so the grid inspector would first list all of the targets that exist in the debuggee (i.e. the debuggee's top level document itself + all nested frames).

However we made it do this only once, when the tool starts.
This means that if new nested frames are added, or existing frames removed, or even when we do a process switch during a page navigation, then the list of targets is going to be outdated.

We should therefore listen to the right events to update this list of targets.
The relevant code is here: https://hg.mozilla.org/mozilla-central/file/tip/devtools/client/inspector/grids/grid-inspector.js#l116

Comment 1

[Patrick Brosset <:pbro>]

The list of grids shown in the grid-inspector is updated on reflow. So I think we should first wait for bug 1580463 to land. And then make changes to the grid-inspector so it listens for reflows in all of the targets it cares about. We should also make it use the TargetList API so it refreshes its list of targets whenever needed.

Comment 2

[Chris Peterson [:cpeterson]]

Tracking for Fission Nightly (M6)

Comment 3

[Chris Peterson [:cpeterson]]

Tracking dt-fission-m2-mvp bugs for Fission Nightly milestone (M6c)

Comment 4

[Julian Descottes [:jdescottes]]

If we show grids from targets other than the top-level target, clicking on them wouldn’t do anything unless we have the CSS Grid Highlighter adapted for Fission.

Blocking on Bug 1572652.

Comment 5

[Neha Kochar [:neha]]

Bulk move of all dt-fission-m2-reserve bugs to Fission MVP milestone.

Comment 6

[Julian Descottes [:jdescottes]]

(In reply to Patrick Brosset <:pbro> from comment #0)

We should therefore listen to the right events to update this list of targets.
The relevant code is here: https://hg.mozilla.org/mozilla-central/file/tip/devtools/client/inspector/grids/grid-inspector.js#l116

https://searchfox.org/mozilla-central/rev/31ddf859c57e812878a5f817e4097efb06de4d97/devtools/client/inspector/grids/grid-inspector.js#118

Comment 7

[Julian Descottes [:jdescottes]]

Verified still happening on today's mozilla-central.

STRs:

• enable fission.autostart
• open https://root-grid-fission.glitch.me/
• open the inspector, select the layout tab (one grid element should be listed in the Grid section)
• click on the "Add new iframe" button

ER: A new grid element should be listed in the Grid section (this is what happens when fission is disabled)
AR: Nothing happens

To fix this, we should use the target list and update the list of layoutFronts when a new target becomes available.
Note that we will also need to update the list when a target gets destroyed (eg removing the frame from the STRs).
We could use a similar pattern as the one found in node-picker.js: targetAvailable + watchFronts("inspector"). See https://searchfox.org/mozilla-central/rev/07342ce09126c513540c1c343476e026cfa907bf/devtools/client/inspector/node-picker.js#127

Comment 8

[Chris Peterson [:cpeterson]]

Moving some dt-fission-m3-mvp bugs from Fission MVP to M7 (blocking Beta experiment).

Comment 9

[Chris Peterson [:cpeterson]]

Tracking dt-fission-m3-mvp test and infrastructure bugs for Fission M8 (blocking Release experiment).

Comment 10

[Chris Peterson [:cpeterson]]

Tracking DevTools Post-M8 bugs for Fission MVP milestone. They don't block the Fission Release channel experiment, but we would like them to be completed before we roll out Fission by default.

Comment 11

[Julian Descottes [:jdescottes]]

Closing as dupe of the newer bug 1707884.
I don't think the existing discussing adds much here.