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Cannot read property 'flags' of undefined

See original GitHub issue

🐞 bug report

Affected Package

Unknown，Just ng new project4 npm start

Is this a regression?

Description

ERROR in TypeError: Cannot read property ‘flags’ of undefined at resolveAlias (E:\Project\aspnet-zero-core-5.5.0\project4\node_modules\typescript\lib\typescript.js:36513:37) at checkAliasSymbol (E:\Project\aspnet-zero-core-5.5.0\project4\node_modules\typescript\lib\typescript.js:64502:26) at checkImportBinding (E:\Project\aspnet-zero-core-5.5.0\project4\node_modules\typescript\lib\typescript.js:64534:13)

🔬 Minimal Reproduction

🔥 Exception or Error




ERROR in TypeError: Cannot read property 'flags' of undefined
    at resolveAlias (E:\Project\aspnet-zero-core-5.5.0\project4\node_modules\typescript\lib\typescript.js:36513:37)
    at checkAliasSymbol (E:\Project\aspnet-zero-core-5.5.0\project4\node_modules\typescript\lib\typescript.js:64502:26)
    at checkImportBinding (E:\Project\aspnet-zero-core-5.5.0\project4\node_modules\typescript\lib\typescript.js:64534:13)
    at checkImportDeclaration (E:\Project\aspnet-zero-core-5.5.0\project4\node_modules\typescript\lib\typescript.js:64552:29)
    at checkSourceElementWorker (E:\Project\aspnet-zero-core-5.5.0\project4\node_modules\typescript\lib\typescript.js:64961:28)
    at checkSourceElement (E:\Project\aspnet-zero-core-5.5.0\project4\node_modules\typescript\lib\typescript.js:64800:17)
    at Object.forEach (E:\Project\aspnet-zero-core-5.5.0\project4\node_modules\typescript\lib\typescript.js:317:30)
    at checkSourceFileWorker (E:\Project\aspnet-zero-core-5.5.0\project4\node_modules\typescript\lib\typescript.js:65123:20)
    at checkSourceFile (E:\Project\aspnet-zero-core-5.5.0\project4\node_modules\typescript\lib\typescript.js:65091:13)
    at getDiagnosticsWorker (E:\Project\aspnet-zero-core-5.5.0\project4\node_modules\typescript\lib\typescript.js:65179:17)
    at Object.getDiagnostics (E:\Project\aspnet-zero-core-5.5.0\project4\node_modules\typescript\lib\typescript.js:65165:24)
    at E:\Project\aspnet-zero-core-5.5.0\project4\node_modules\typescript\lib\typescript.js:98703:85
    at runWithCancellationToken (E:\Project\aspnet-zero-core-5.5.0\project4\node_modules\typescript\lib\typescript.js:98665:24)
    at getBindAndCheckDiagnosticsForFileNoCache (E:\Project\aspnet-zero-core-5.5.0\project4\node_modules\typescript\lib\typescript.js:98691:20)
    at getAndCacheDiagnostics (E:\Project\aspnet-zero-core-5.5.0\project4\node_modules\typescript\lib\typescript.js:98956:26)
    at getBindAndCheckDiagnosticsForFile (E:\Project\aspnet-zero-core-5.5.0\project4\node_modules\typescript\lib\typescript.js:98688:20)

🌍 Your Environment

Angular Version:




Angular CLI: 9.1.4
Node: 14.2.0
OS: win32 x64

Angular: 9.1.5
... animations, common, compiler, compiler-cli, core, forms
... language-service, platform-browser, platform-browser-dynamic
... router
Ivy Workspace: Yes

Package                           Version
-----------------------------------------------------------
@angular-devkit/architect         0.901.4
@angular-devkit/build-angular     0.901.4
@angular-devkit/build-optimizer   0.901.4
@angular-devkit/build-webpack     0.901.4
@angular-devkit/core              9.1.4
@angular-devkit/schematics        9.1.4
@angular/cli                      9.1.4
@ngtools/webpack                  9.1.4
@schematics/angular               9.1.4
@schematics/update                0.901.4
rxjs                              6.5.5
typescript                        3.8.3
webpack                           4.42.0

Anything else relevant?