Debug Failure. Unhandled Diagnostic: 2626

[k-yle]

Bug Report

Regression in v4.2.1-rc (EDIT: also an issue in v4.2.2), tsc fails to compile with an error Debug Failure. Unhandled Diagnostic: 2626. It worked fine in v4.2.0-beta

🔎 Search Terms

🕗 Version & Regression Information

• This is a crash
• This changed between versions v4.2.1-beta and v4.2.2-rc
• This is the behaviour in every version I tried, and I reviewed the FAQ for entries about "Debug Failure. Unhandled Diagnostic: 2626"
• I was unable to test this on prior versions because _______

⏯ Playground Link

Playground link with relevant code

💻 Code

// I don't have a simple reproduction, this occurs in our ~60,000 SLOC codebase which is 50% Javascript using checkJs mode

tsconfig:

{
  "compilerOptions": {
    "target": "es5",
    "lib": ["dom", "dom.iterable", "es2020"],
    "allowJs": true,
    "checkJs": true,
    "skipLibCheck": true,
    "esModuleInterop": true,
    "allowSyntheticDefaultImports": true,
    "strict": true,
    "forceConsistentCasingInFileNames": true,
    "module": "esnext",
    "moduleResolution": "node",
    "resolveJsonModule": true,
    "isolatedModules": true,
    "noEmit": true,
    "jsx": "react-jsx",
    "noFallthroughCasesInSwitch": true,

    "downlevelIteration": true,
    "importHelpers": true,
    "strictNullChecks": true,
    "noImplicitAny": false,
    "baseUrl": "src"
  },
  "include": ["src"],

  "exclude": ["cypress", "src/**/__tests__/*.test.*"],
  "typeAcquisition": {
    "include": ["jest"],
    "exclude": ["chai", "cypress"]
  }
}

🙁 Actual behaviour

TSC crashes and fails to compile

$ yarn tsc --extendedDiagnostics

...\node_modules\typescript\lib\tsc.js:88040
                throw e;
                ^

Error: Debug Failure. Unhandled Diagnostic: 2626
    at reportIncompatibleStack (...\node_modules\typescript\lib\tsc.js:49104:45)
    at checkTypeRelatedTo (...\node_modules\typescript\lib\tsc.js:48976:17)
    at checkTypeRelatedToAndOptionallyElaborate (...\node_modules\typescript\lib\tsc.js:48255:24)
    at checkTypeAssignableToAndOptionallyElaborate (...\node_modules\typescript\lib\tsc.js:48249:20)
    at checkVariableLikeDeclaration (...\node_modules\typescript\lib\tsc.js:62811:25)
    at checkVariableDeclaration (...\node_modules\typescript\lib\tsc.js:62876:13)
    at checkSourceElementWorker (...\node_modules\typescript\lib\tsc.js:65151:28)
    at checkSourceElement (...\node_modules\typescript\lib\tsc.js:64999:17)
    at Object.forEach (...\node_modules\typescript\lib\tsc.js:128:30)
    at checkVariableStatement (...\node_modules\typescript\lib\tsc.js:62886:16)

🙂 Expected behaviour

It should compile, which worked in v4.2 beta

[RyanCavanaugh]

@armanio123 looks like we're straightforwardly missing a case in reportIncompatibleStack. This might be difficult to construct a test for but we can write another case for code 2626 there.

[stevehollaar]

I'm hitting this as well with typescript 4.2.2, in a large project with the following tsconfig.json:

{
  "compilerOptions": {
    "baseUrl": "./",
    "jsx": "preserve",
    "noEmit": true,
    "module": "esnext",
    "esModuleInterop": true,
    "strict": true,
    "alwaysStrict": true,
    "noImplicitThis": false,
    "resolveJsonModule": true,
    "moduleResolution": "node",
    "downlevelIteration": true,
    "allowSyntheticDefaultImports": true,
    "skipLibCheck": true,
    "paths": {
      "~/*": ["./src/*"],
      "test/*": ["./test/*"],
      "*": ["./typings/*"]
    },
    "lib": ["es2015", "es2016", "es2017", "es2018", "esnext", "dom"],
    "target": "ES2020"
  },
  "include": ["src", "typings"],
  "exclude": [
    "node_modules",
    "public",
    "lib",
    "./src/**/__tests__/*.legacy-unit-test.ts",
    "./src/**/__tests__/*-itest.ts"
  ]
}

$ tsc -p .                                                                                                   
/app/node_modules/typescript/lib/tsc.js:88051
                throw e;
                ^

Error: Debug Failure. Unhandled Diagnostic: 2626
    at reportIncompatibleStack (/app/node_modules/typescript/lib/tsc.js:49104:45)
    at reportRelationError (/app/node_modules/typescript/lib/tsc.js:49145:21)
    at reportErrorResults (/app/node_modules/typescript/lib/tsc.js:49338:25)
    at isRelatedTo (/app/node_modules/typescript/lib/tsc.js:49299:17)
    at typeArgumentsRelatedTo (/app/node_modules/typescript/lib/tsc.js:49573:39)
    at relateVariances (/app/node_modules/typescript/lib/tsc.js:50032:34)
    at structuredTypeRelatedToWorker (/app/node_modules/typescript/lib/tsc.js:49982:46)
    at structuredTypeRelatedTo (/app/node_modules/typescript/lib/tsc.js:49689:30)
    at recursiveTypeRelatedTo (/app/node_modules/typescript/lib/tsc.js:49665:53)
    at isRelatedTo (/app/node_modules/typescript/lib/tsc.js:49279:34)

[RyanCavanaugh]

@stevehollaar any chance you could share code that reproduces the issue? That would help us out a ton

[stevehollaar]

@stevehollaar any chance you could share code that reproduces the issue? That would help us out a ton

Unfortunately the codebase is proprietary and I wasn't able to isolate a small repro.

I ended up debugging this by adding a console.log line:

console.log({source, sourceType });

in tsc.js, just prior to this line:

reportIncompatibleError(ts.Diagnostics.Type_at_position_0_in_source_is_not_compatible_with_type_at_position_1_in_target, sourceIndex, i);

That gave me:

{
  source: Type {
    flags: 524288,
    id: 117489,
    symbol: undefined,
    objectFlags: 1114116,
    target: <ref *1> Type {
      flags: 524288,
      id: 1048,
      objectFlags: 12,
      symbol: undefined,
      members: undefined,
      properties: undefined,
      callSignatures: undefined,
      constructSignatures: undefined,
      stringIndexInfo: undefined,
      numberIndexInfo: undefined,
      typeParameters: [Array],
      outerTypeParameters: undefined,
      localTypeParameters: [Array],
      instantiations: [Map],
      target: [Circular *1],
      resolvedTypeArguments: [Array],
      thisType: [Type],
      declaredProperties: [Array],
      declaredCallSignatures: [],
      declaredConstructSignatures: [],
      declaredStringIndexInfo: undefined,
      declaredNumberIndexInfo: undefined,
      elementFlags: [Array],
      minLength: 2,
      fixedLength: 2,
      hasRestElement: false,
      combinedFlags: 1,
      readonly: false,
      labeledElementDeclarations: undefined,
      resolvedBaseTypes: [Array],
      baseTypesResolved: true
    },
    resolvedTypeArguments: [ [Type], [Type] ],
    members: Map(36) {
      '0' => [Symbol],
      '1' => [Symbol],
      'length' => [Symbol],
      'toString' => [Symbol],
      'toLocaleString' => [Symbol],
      'pop' => [Symbol],
      'push' => [Symbol],
      'concat' => [Symbol],
      'join' => [Symbol],
      'reverse' => [Symbol],
      'shift' => [Symbol],
      'slice' => [Symbol],
      'sort' => [Symbol],
      'splice' => [Symbol],
      'unshift' => [Symbol],
      'indexOf' => [Symbol],
      'lastIndexOf' => [Symbol],
      'every' => [Symbol],
      'some' => [Symbol],
      'forEach' => [Symbol],
      'map' => [Symbol],
      'filter' => [Symbol],
      'reduce' => [Symbol],
      'reduceRight' => [Symbol],
      'find' => [Symbol],
      'findIndex' => [Symbol],
      'fill' => [Symbol],
      'copyWithin' => [Symbol],
      '__@iterator' => [Symbol],
      'entries' => [Symbol],
      'keys' => [Symbol],
      'values' => [Symbol],
      '__@unscopables' => [Symbol],
      'includes' => [Symbol],
      'flatMap' => [Symbol],
      'flat' => [Symbol]
    },
    properties: [
      [Symbol], [Symbol], [Symbol], [Symbol],
      [Symbol], [Symbol], [Symbol], [Symbol],
      [Symbol], [Symbol], [Symbol], [Symbol],
      [Symbol], [Symbol], [Symbol], [Symbol],
      [Symbol], [Symbol], [Symbol], [Symbol],
      [Symbol], [Symbol], [Symbol], [Symbol],
      [Symbol], [Symbol], [Symbol], [Symbol],
      [Symbol], [Symbol], [Symbol], [Symbol],
      [Symbol], [Symbol], [Symbol], [Symbol]
    ],
    callSignatures: [],
    constructSignatures: [],
    stringIndexInfo: undefined,
    numberIndexInfo: { type: [Type], isReadonly: false, declaration: [Node] }
  },
  sourceType: Type {
    flags: 524288,
    id: 117487,
    objectFlags: 16,
    symbol: Symbol {
      flags: 4096,
      escapedName: '__object',
      declarations: [Array],
      valueDeclaration: [Node],
      id: undefined,
      mergeId: undefined,
      parent: undefined,
      members: [Map]
    },
    members: Map(3) {
      'notificationId' => [Symbol],
      'getTemplateData' => [Symbol],
      'generateStartEndDate' => [Symbol]
    },
    properties: [ [Symbol], [Symbol], [Symbol] ],
    callSignatures: [],
    constructSignatures: [],
    stringIndexInfo: undefined,
    numberIndexInfo: undefined
  }
}

just prior to the tsc error, and from there I was able to find the problematic code via the sourceType.members.

I think there must have been something funky about the way types were shared across module boundaries (possibly related to a circular reference?), as when I tried to repro in the playground, I could not. My "fix" was to explicitly type some exported objects with a shared interface, instead of leaving the type as implicit. I hope this helps!

[ItWorksOnMyMachine]

I'm getting something very similar, but not exactly the same. It compiles fine with 4.1.5 but fails with the error below in 4.2.2. We are using webpack and I'm logging the ts file name as it's being processed, and unfortunately, it's not always happening on the same file. I don't have an easy repro, this solution is proprietary and also contains thousands of typescript files. At first I thought it was when exporting an enum where the enum's values were strings. I noticed the ones that it was crashing on were strings using a single quote and not a double quote, so I changed it, and it seemed to no longer fail on that file. However, I'm no longer certain that's the issue as it's now failing on a file with a large exported class. This class has no members that are strings, although it does use strings in one method, and those strings have single quotes. It's too much to change every file in the project as a test, but this seems like correlation but not necessarily causation anyway. At this point, we are rolling back to 4.1.5.

Error: Debug Failure. Error: Debug Failure. at Object.getModuleSpecifiers (C:\dev\Workspaces\Git\Project\node_modules\.pnpm\typescript@4.2.2\node_modules\typescript\lib\typescript.js:111579:30) at getSpecifierForModuleSymbol (C:\dev\Workspaces\Git\Project\node_modules\.pnpm\typescript@4.2.2\node_modules\typescript\lib\typescript.js:48852:62) at C:\dev\Workspaces\Git\Project\node_modules\.pnpm\typescript@4.2.2\node_modules\typescript\lib\typescript.js:48710:39 at Array.map (<anonymous>) at getSymbolChain (C:\dev\Workspaces\Git\Project\node_modules\.pnpm\typescript@4.2.2\node_modules\typescript\lib\typescript.js:48708:58) at getSymbolChain (C:\dev\Workspaces\Git\Project\node_modules\.pnpm\typescript@4.2.2\node_modules\typescript\lib\typescript.js:48718:51) at lookupSymbolChainWorker (C:\dev\Workspaces\Git\Project\node_modules\.pnpm\typescript@4.2.2\node_modules\typescript\lib\typescript.js:48692:51) at lookupSymbolChain (C:\dev\Workspaces\Git\Project\node_modules\.pnpm\typescript@4.2.2\node_modules\typescript\lib\typescript.js:48685:24) at symbolToTypeNode (C:\dev\Workspaces\Git\Project\node_modules\.pnpm\typescript@4.2.2\node_modules\typescript\lib\typescript.js:48859:29) at typeReferenceToTypeNode (C:\dev\Workspaces\Git\Project\node_modules\.pnpm\typescript@4.2.2\node_modules\typescript\lib\typescript.js:48272:40)

[heikkis]

I had same problem. For me it was that I used string as an enum instead of using the actual enum as value.

[ItWorksOnMyMachine]

@heikkis , We use them all over the place. The language allows it: https://www.typescriptlang.org/docs/handbook/enums.html.

[flybayer]

I'm having the same error as @ItWorksOnMyMachine.

And I have a small reproduction repo: https://github.com/flybayer/tsc-broken (boilerplate for a new Blitz app)

1. git clone git@github.com:flybayer/tsc-broken.git
2. cd tsc-broken
3. yarn
4. yarn tsc

[bebraw]

In my case, I had code like this that crashed with a 2626 that was hard to debug:

import { defineMessages } from 'react-intl';

type UserSource = 'google' | 'slack' | 'microsoft'

type SourceInfo = {
  key: string;
  icon: ReactNode;
  label: { id: string; defaultMessage: string; description: string };
};

const messages = defineMessages({
  slackProvider: {
    id: 'fabric.elements.user-picker.slack.provider',
    defaultMessage: 'Slack',
    description: 'This external user is sourced from Slack provider',
  },
});

// @ts-ignore
const SourcesInfoMap = new Map<UserSource, SourceInfo>([
  ["slack", { key: "slack", icon: <SlackIcon />, label: messages.slackProvider }]
]);

The code doesn't run but I hope it gives you enough idea to tell what the issue is about.

The weird thing is that it crashed even with that // @ts-ignore in place. The fix was to change the declaration to <UserSource, any> instead of <UserSource, SourceInfo> although I know that's not particularly nice.

It's possible there was some issue in the original code that was uncovered by the update to TypeScript 4.2.