typescript-language-features doesn't work on MemFS

[tamuratak]

Version: 1.56.0-insider
Commit: cfa2e21
Date: 2021-05-04T21:55:28.605Z
Electron: 12.0.4
Chrome: 89.0.4389.114
Node.js: 14.16.0
V8: 8.9.255.24-electron.0
OS: Darwin x64 18.7.0

Related to #59650 (comment) and #122836.

Steps to Reproduce:

1. Install MemFS https://marketplace.visualstudio.com/items?itemName=jrieken.vscode-memfs
2. Execute MemFS Setup Workspace
3. Create a t.ts file
4. Initializing JS/TS language features has started. But, it never ends.

Does this issue occur when all extensions are disabled?: Yes

The dev console says:

  ERR Error: Unable to read file 'memfs:/t.ts' (Error: Unable to resolve non-existing file 'memfs:/t.ts')
    at n (errors.ts:246)
    at i.handleSetInputError (textFileEditor.ts:177)
    at i.handleSetInputError (textFileEditor.ts:82)
    at i.setInput (textFileEditor.ts:155)
    at async l.doSetInput (editorControl.ts:177)
    at async l.openEditor (editorControl.ts:66)
    at async file:/Applications/Visual Studio Code - Insiders.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js:2452

event.ts:488     at file:///Applications/Visual Studio Code - Insiders.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js:58:58523
    at file:///Applications/Visual Studio Code - Insiders.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js:58:61006
    at new Promise (<anonymous>)
    at Object.N [as toPromise] (file:///Applications/Visual Studio Code - Insiders.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js:58:60987)
    at _.whenInitialized (file:///Applications/Visual Studio Code - Insiders.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js:76:4475)
    at file:///Applications/Visual Studio Code - Insiders.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js:76:2720
    at w (file:///Applications/Visual Studio Code - Insiders.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js:68:11210)
    at file:///Applications/Visual Studio Code - Insiders.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js:76:2710
    at new Promise (<anonymous>)
    at _.requestPromise (file:///Applications/Visual Studio Code - Insiders.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js:76:2252)
    at Object.call (file:///Applications/Visual Studio Code - Insiders.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js:76:1941)
    at file:///Applications/Visual Studio Code - Insiders.app/Contents/Resources/app/out/vs/workbench/workbench.desktop.main.js:76:7092
check @ event.ts:488
_event._event @ event.ts:565
(anonymous) @ event.ts:31
(anonymous) @ event.ts:377
N @ event.ts:377
whenInitialized @ ipc.ts:730
(anonymous) @ ipc.ts:590
w @ async.ts:25
(anonymous) @ ipc.ts:590
requestPromise @ ipc.ts:554
call @ ipc.ts:532
(anonymous) @ ipc.ts:962

[vscodebot]

(Experimental duplicate detection)
Thanks for submitting this issue. Please also check if it is already covered by an existing one, like:

• ChannelClient#onDidInitialize: potential listener LEAK detected (#121989)
• Loading an untrusted Codespace through an error on terminal tabs (#121702)
• TerminalTabsTree crash (#121691)
• ERR Cannot read property 'nextElementSibling' of undefined (#119611)
• tabSize=1 prevent typing a string matching decreaseIndentPattern in an empty file (#122714)