potential listener LEAK detected, having 185 listeners already.

[jrieken]

Testing #210961

• todays insiders 347777655976bbc8460f833449592dd0a9a8f340
• having a really large ipynb notebook
• 🐛 seeing the leak warning below

event.ts:875 [72h] potential listener LEAK detected, having 185 listeners already. MOST frequent listener (8):
check @ event.ts:875
q @ event.ts:1056
M @ menuService.ts:395
q @ event.ts:1064
m @ notebookOutline.ts:217
renderElement @ notebookOutline.ts:182
renderElement @ abstractTree.ts:418
renderElement @ listWidget.ts:1249
Z @ listView.ts:940
(anonymous) @ listView.ts:876
transact @ rowCache.ts:80
Y @ listView.ts:867
ib @ listView.ts:1107
y @ event.ts:1156
z @ event.ts:1167
fire @ event.ts:1191
(anonymous) @ scrollableElement.ts:216
y @ event.ts:1156
fire @ event.ts:1187
n @ scrollable.ts:393
setScrollPositionNow @ scrollable.ts:303
R @ scrollableElement.ts:470
$ @ scrollableElement.ts:382
event.ts:876 Error
    at c.create (event.ts:889:25)
    at l.q [as onDidChange] (event.ts:1055:34)
    at Object.M [as onWillAddFirstListener] (menuService.ts:395:34)
    at f.q [as onDidChange] (event.ts:1064:20)
    at O.m (notebookOutline.ts:217:44)
    at O.renderElement (notebookOutline.ts:182:9)
    at A.renderElement (abstractTree.ts:418:17)
    at Y.renderElement (listWidget.ts:1249:13)
    at m.Z (listView.ts:940:13)
    at listView.ts:876:11
    at E.transact (rowCache.ts:80:4)
    at m.Y (listView.ts:867:14)
    at m.ib (listView.ts:1107:9)
    at n.y (event.ts:1156:13)
    at n.z (event.ts:1167:9)
    at n.fire (event.ts:1191:9)
    at d.value (scrollableElement.ts:216:19)
    at n.y (event.ts:1156:13)
    at n.fire (event.ts:1187:9)
    at I.n (scrollable.ts:393:18)
    at I.setScrollPositionNow (scrollable.ts:303:8)
    at n.setScrollPosition (scrollableElement.ts:619:21)
    at m.setScrollTop (listView.ts:1030:26)
    at X.reveal (listWidget.ts:1909:14)
    at ie.reveal (abstractTree.ts:2989:14)
    at d.H [as value] (outlinePane.ts:332:11)
    at n.y (event.ts:1156:13)
    at n.z (event.ts:1167:9)
    at n.fire (event.ts:1191:9)
    at d.value (notebookOutline.ts:375:24)
    at n.y (event.ts:1156:13)
    at n.z (event.ts:1167:9)
    at n.fire (event.ts:1191:9)
    at u.r (notebookOutlineProvider.ts:298:22)
    at notebookOutlineProvider.ts:57:79
    at async.ts:364:13
check @ event.ts:876
q @ event.ts:1056
M @ menuService.ts:395
q @ event.ts:1064
m @ notebookOutline.ts:217
renderElement @ notebookOutline.ts:182
renderElement @ abstractTree.ts:418
renderElement @ listWidget.ts:1249
Z @ listView.ts:940
(anonymous) @ listView.ts:876
transact @ rowCache.ts:80
Y @ listView.ts:867
ib @ listView.ts:1107
y @ event.ts:1156
z @ event.ts:1167
fire @ event.ts:1191
(anonymous) @ scrollableElement.ts:216
y @ event.ts:1156
fire @ event.ts:1187
n @ scrollable.ts:393
setScrollPositionNow @ scrollable.ts:303
R @ scrollableElement.ts:470
$ @ scrollableElement.ts:382

[jrieken]

Looks like this is coming from here:

vscode/src/vs/workbench/contrib/notebook/browser/contrib/outline/notebookOutline.ts

Line 217 in a49c81e

templateData.elementDisposables.add(menu.onDidChange(() => {

Setting up a listener per rendered element isn't great, it's better to have one and share it with the elements

[jrieken]

This is the notebook I am testing with: slow.ipynb.txt

[jrieken]

same/related #211112