TS Server fatal error: Cannot read property 'flags' of undefined

[pvjones]

Issue Type: Bug

❗️❗️❗️ Please fill in the sections below to help us diagnose the issue ❗️❗️❗️

TypeScript Version: 4.5.4

Steps to reproduce crash

1. Open VSCode
2. Open any file in project

TS Server Log
❗️ Please review and upload this log file to help us diagnose this crash:
/Users/paul/Library/Application Support/Code/logs/20220110T155714/exthost3/vscode.typescript-language-features/tsserver-log-y4eAuK/tsserver.log
The log file may contain personal data, including full paths and source code from your workspace. You can scrub the log file to remove paths or other personal information.

TS Server Error Stack
Server: semantic

TypeError: Cannot read property 'flags' of undefined
    at getPropertyOfObjectType (/Applications/Visual Studio Code.app/Contents/Resources/app/extensions/node_modules/typescript/lib/tsserver.js:57011:22)
    at getPropertyOfType (/Applications/Visual Studio Code.app/Contents/Resources/app/extensions/node_modules/typescript/lib/tsserver.js:57671:24)
    at resolveESModuleSymbol (/Applications/Visual Studio Code.app/Contents/Resources/app/extensions/node_modules/typescript/lib/tsserver.js:49817:54)
    at getTargetOfNamespaceImport (/Applications/Visual Studio Code.app/Contents/Resources/app/extensions/node_modules/typescript/lib/tsserver.js:49002:28)
    at getTargetOfAliasDeclaration (/Applications/Visual Studio Code.app/Contents/Resources/app/extensions/node_modules/typescript/lib/tsserver.js:49236:28)
    at resolveAlias (/Applications/Visual Studio Code.app/Contents/Resources/app/extensions/node_modules/typescript/lib/tsserver.js:49281:30)
    at getSymbol (/Applications/Visual Studio Code.app/Contents/Resources/app/extensions/node_modules/typescript/lib/tsserver.js:47838:38)
    at resolveNameHelper (/Applications/Visual Studio Code.app/Contents/Resources/app/extensions/node_modules/typescript/lib/tsserver.js:48131:34)
    at resolveName (/Applications/Visual Studio Code.app/Contents/Resources/app/extensions/node_modules/typescript/lib/tsserver.js:48114:20)
    at resolveEntityName (/Applications/Visual Studio Code.app/Contents/Resources/app/extensions/node_modules/typescript/lib/tsserver.js:49453:42)
    at getTargetOfExportSpecifier (/Applications/Visual Studio Code.app/Contents/Resources/app/extensions/node_modules/typescript/lib/tsserver.js:49193:17)
    at getTargetOfAliasDeclaration (/Applications/Visual Studio Code.app/Contents/Resources/app/extensions/node_modules/typescript/lib/tsserver.js:49243:28)
    at resolveAlias (/Applications/Visual Studio Code.app/Contents/Resources/app/extensions/node_modules/typescript/lib/tsserver.js:49281:30)
    at resolveSymbol (/Applications/Visual Studio Code.app/Contents/Resources/app/extensions/node_modules/typescript/lib/tsserver.js:49271:67)
    at mergeSymbol (/Applications/Visual Studio Code.app/Contents/Resources/app/extensions/node_modules/typescript/lib/tsserver.js:47624:42)
    at /Applications/Visual Studio Code.app/Contents/Resources/app/extensions/node_modules/typescript/lib/tsserver.js:47739:47
    at Map.forEach (<anonymous>)
    at mergeSymbolTable (/Applications/Visual Studio Code.app/Contents/Resources/app/extensions/node_modules/typescript/lib/tsserver.js:47737:20)
    at mergeSymbol (/Applications/Visual Studio Code.app/Contents/Resources/app/extensions/node_modules/typescript/lib/tsserver.js:47648:21)
    at /Applications/Visual Studio Code.app/Contents/Resources/app/extensions/node_modules/typescript/lib/tsserver.js:47739:47
    at Map.forEach (<anonymous>)
    at mergeSymbolTable (/Applications/Visual Studio Code.app/Contents/Resources/app/extensions/node_modules/typescript/lib/tsserver.js:47737:20)
    at initializeTypeChecker (/Applications/Visual Studio Code.app/Contents/Resources/app/extensions/node_modules/typescript/lib/tsserver.js:85010:21)
    at Object.createTypeChecker (/Applications/Visual Studio Code.app/Contents/Resources/app/extensions/node_modules/typescript/lib/tsserver.js:47395:9)
    at Object.getTypeChecker (/Applications/Visual Studio Code.app/Contents/Resources/app/extensions/node_modules/typescript/lib/tsserver.js:114404:79)
    at synchronizeHostData (/Applications/Visual Studio Code.app/Contents/Resources/app/extensions/node_modules/typescript/lib/tsserver.js:159898:21)
    at Object.getProgram (/Applications/Visual Studio Code.app/Contents/Resources/app/extensions/node_modules/typescript/lib/tsserver.js:160019:13)
    at ConfiguredProject.Project.updateGraphWorker (/Applications/Visual Studio Code.app/Contents/Resources/app/extensions/node_modules/typescript/lib/tsserver.js:165033:53)
    at ConfiguredProject.Project.updateGraph (/Applications/Visual Studio Code.app/Contents/Resources/app/extensions/node_modules/typescript/lib/tsserver.js:164962:42)
    at ConfiguredProject.updateGraph (/Applications/Visual Studio Code.app/Contents/Resources/app/extensions/node_modules/typescript/lib/tsserver.js:165955:63)
    at ProjectService.createLoadAndUpdateConfiguredProject (/Applications/Visual Studio Code.app/Contents/Resources/app/extensions/node_modules/typescript/lib/tsserver.js:167679:25)
    at ProjectService.assignProjectToOpenedScriptInfo (/Applications/Visual Studio Code.app/Contents/Resources/app/extensions/node_modules/typescript/lib/tsserver.js:168762:44)
    at /Applications/Visual Studio Code.app/Contents/Resources/app/extensions/node_modules/typescript/lib/tsserver.js:169102:97
    at Object.flatMap (/Applications/Visual Studio Code.app/Contents/Resources/app/extensions/node_modules/typescript/lib/tsserver.js:522:25)
    at ProjectService.applyChangesInOpenFiles (/Applications/Visual Studio Code.app/Contents/Resources/app/extensions/node_modules/typescript/lib/tsserver.js:169102:41)
    at Session.handlers.ts.Map.ts.getEntries._a.<computed> (/Applications/Visual Studio Code.app/Contents/Resources/app/extensions/node_modules/typescript/lib/tsserver.js:170260:46)
    at /Applications/Visual Studio Code.app/Contents/Resources/app/extensions/node_modules/typescript/lib/tsserver.js:172193:88
    at IOSession.Session.executeWithRequestId (/Applications/Visual Studio Code.app/Contents/Resources/app/extensions/node_modules/typescript/lib/tsserver.js:172184:28)
    at IOSession.Session.executeCommand (/Applications/Visual Studio Code.app/Contents/Resources/app/extensions/node_modules/typescript/lib/tsserver.js:172193:33)
    at IOSession.Session.onMessage (/Applications/Visual Studio Code.app/Contents/Resources/app/extensions/node_modules/typescript/lib/tsserver.js:172219:35)
    at Interface.<anonymous> (/Applications/Visual Studio Code.app/Contents/Resources/app/extensions/node_modules/typescript/lib/tsserver.js:174824:31)
    at Interface.emit (events.js:315:20)
    at Interface._onLine (readline.js:337:10)
    at Interface._normalWrite (readline.js:482:12)
    at Socket.ondata (readline.js:194:10)
    at Socket.emit (events.js:315:20)
    at addChunk (internal/streams/readable.js:309:12)
    at readableAddChunk (internal/streams/readable.js:284:9)
    at Socket.Readable.push (internal/streams/readable.js:223:10)
    at Pipe.onStreamRead (internal/stream_base_commons.js:188:23)

VS Code version: Code 1.63.2 (899d46d, 2021-12-15T09:38:17.605Z)
OS version: Darwin arm64 21.2.0
Restricted Mode: No

System Info

Item	Value
CPUs	Apple M1 Max (10 x 24)
GPU Status	2d_canvas: enabled gpu_compositing: enabled metal: disabled_off multiple_raster_threads: enabled_on oop_rasterization: enabled opengl: enabled_on rasterization: enabled skia_renderer: disabled_off_ok video_decode: enabled webgl: enabled webgl2: enabled
Load (avg)	3, 4, 7
Memory (System)	32.00GB (4.38GB free)
Process Argv	--crash-reporter-id 85c03ea0-6e69-487f-859d-5d75064673ea
Screen Reader	no
VM	0%

Extensions: none (1 theme extensions excluded)

A/B Experiments

vsliv368:30146709
vsreu685:30147344
python383:30185418
vspor879:30202332
vspor708:30202333
vspor363:30204092
pythontb:30283811
pythonvspyt551:30345470
pythonptprofiler:30281270
vshan820:30294714
vstes263:30335439
pythondataviewer:30285071
vscod805:30301674
pythonvspyt200:30340761
binariesv615:30325510
bridge0708:30335490
bridge0723:30353136
vsaa593cf:30376535
pythonvs932:30410667
vscop804:30404766
vscop453:30404998
vsrem710:30416614

[pvjones]

I've tried disabling extensions as well as installing the insider's version of VSCode. Error still occurs in each case.

[pvjones]

This appears to be a problem with the latest version of VSCode. Problem occurs on both 1.63.2 and the latest insiders version. After downgrading to 1.62.3, the problem goes away.

[IllusionMH]

/duplicate of microsoft/TypeScript#47179

Problem is with bundled version of TS. You can configure VS Code to use different version of TS (lower than bundled, but still use latest VS Code) until fix merged

[vscode-triage-bot]

Thanks for creating this issue! We figured it's covering the same as another one we already have. Thus, we closed this one as a duplicate. You can search for similar existing issues. See also our issue reporting guidelines.

Happy Coding!