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Combine reducers with intersected type of unions causes tsc to crash

See original GitHub issue

TypeScript Version: 3.4.0-dev.201xxxxx Typescript version: 3.4.5

Search Terms: Redux combine reducers memory crash heap allocation


// es6 import statements for actions and reducers

type FormActions = SignUpFormActionTypes &
  LoginFormActionTypes &
  ContactUsFormActionTypes &
  ForgotPasswordFormActionTypes &
  ResetPasswordFormActionTypes &
  CreateBusinessFormActionTypes &
  BusinessDetailsFormActionTypes &
  DealFormActionsTypes &
  InstantDealFormActionsTypes &
  JobListingFormActionTypes &
  OnlineLocationFormActionTypes &

export default combineReducers<FormsState, FormActions>({
  signUpForm: SignUpFormReducer,
  loginForm: LoginFormReducer,
  contactUsForm: ContactUsFormReducer,
  forgotPasswordForm: ForgotPasswordFormReducer,
  resetPasswordForm: ResetPasswordFormReducer,
  createBusinessForm: CreateBusinessFormReducer,
  businessDetailsForm: BusinessDetailsFormReducer,
  dealForm: DealFormReducer,
  instantDealForm: InstantDealFormReducer,
  jobListingForm: JobListingFormReducer,
  onlineLocationForm: OnlineLocationFormReducer,
  physicalLocationForm: PhysicalLocationFormReducer,

For example, an action type looks like this:

export type LoginFormActionTypes =
  | SubmitLoginAction
  | LoginSuccessAction
  | LoginFailedAction;

And each of those actions are plain javascript classes that implement from Action<> in the redux library

Expected behavior: Should run tsc without issues

Actual behavior: npx tsc

<— Last few GCs —>

[59352:0000023E65B36200] 42665 ms: Mark-sweep 1391.2 (1425.2) -> 1390.9 (1425.7) MB, 966.8 / 0.0 ms (average mu = 0.081, current mu = 0.003) allocation failure scavenge might not succeed [59352:0000023E65B36200] 43644 ms: Mark-sweep 1391.8 (1425.7) -> 1391.4 (1426.2) MB, 952.3 / 0.0 ms (average mu = 0.055, current mu = 0.027) allocation failure scavenge might not succeed

<— JS stacktrace —>

==== JS stack trace =========================================

0: ExitFrame [pc: 000002A7DB3DC5C1]
1: StubFrame [pc: 000002A7DB3A26EE]

Security context: 0x030e7eb1e6e1 <JSObject> 2: slice [0000030E7EB06D09](this=0x03034251dc11 <JSArray[12]>,0) 3: /* anonymous /(aka / anonymous */) [000003034251DCC9] [D:\Workspace\business-portal\node_modules\typescript\lib\tsc.js:~33214] [pc=000002A7DC4AFFD1](this=0x0054b7c826f1 <undefined>,t=0x0074346aaf91 <Type map = 0000002A182ED9C9>) 4: argu…

FATAL ERROR: Ineffective mark-compacts near heap limit Allocation failed - JavaScript heap out of memory 1: 00007FF79DD9ECF5 2: 00007FF79DD781A6 3: 00007FF79DD78BB0 4: 00007FF79E009AAE 5: 00007FF79E0099DF 6: 00007FF79E547724 7: 00007FF79E53DE87 8: 00007FF79E53C3FC 9: 00007FF79E545377 10: 00007FF79E5453F6 11: 00007FF79E0E84B7 12: 00007FF79E18019A 13: 000002A7DB3DC5C1

When I replace the action type of combineReducers to combineReducers<FormsState, any>, tsc runs and webpack compiles with linting.

These are my compiler options in tsconfig

"compilerOptions: {
    "outDir": "dist",
    "sourceMap": true,
    "allowSyntheticDefaultImports": true,
    "declaration": false,
    "noFallthroughCasesInSwitch": true,
    "importHelpers": true,
    "noEmitHelpers": true,
    "noImplicitAny": true,
    "skipLibCheck": true,
    "strictNullChecks": true,
    "noImplicitThis": true,
    "alwaysStrict": true,
    "isolatedModules": true,
    "allowJs": true,
    "checkJs": true,
    "module": "es2015",
    "noImplicitReturns": true,
    "emitDecoratorMetadata": true,
    "experimentalDecorators": true,
    "moduleResolution": "node",
    "resolveJsonModule": true,
    "strict": true,
    "pretty": true,
    "removeComments": true,
    "target": "es5",
    "jsx": "react"

When I remove two or more declared action(s) that are part of the intersected FormActions type, tsc compiles again.

Related Issues:

Issue Analytics

  • State:open
  • Created 4 years ago
  • Comments:7 (4 by maintainers)

github_iconTop GitHub Comments

ajafffcommented, May 7, 2019

How can one reproduce this without knowing the types of your Actions and Reducers?

Also please fix the formatting of the opening post. It’s a pain to read.

amcaseycommented, Nov 17, 2022

I have no recollection of why this ceased to be Needs Investigation or why I grabbed it.

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