[dot-notation] False positive with optional chaining and `allowIndexSignaturePropertyAccess: true` #3510

kohlmannj · 2021-06-09T19:02:55Z

I have tried restarting my IDE and the issue persists.
I have updated to the latest version of the packages.
I have read the FAQ and my problem is not listed.

Repro

{
  "parser": "@typescript-eslint/parser",
  "parserOptions": {
    "project": "tsconfig.json"
  },
  "plugins": ["@typescript-eslint"],
  "rules": {
    "@typescript-eslint/dot-notation": [
      "error",
      {
        "allowIndexSignaturePropertyAccess": true
      }
    ]
  }
}

interface Nested {
  property: string;

  [key: string]: number | string;
}

interface Dingus {
  nested: Nested;
}

let dingus: Dingus | undefined;

dingus?.nested.property;
dingus?.nested['hello'];

{
  "compilerOptions": {
    /* Basic Options */
    "lib": ["DOM", "DOM.Iterable", "ES2020"],
    "module": "ES2020",
    "target": "ES2020",

    /* Module Resolution Options */
    "moduleResolution": "node",
    "resolveJsonModule": true,
    "esModuleInterop": true,
    "preserveSymlinks": true,

    /* Experimental Options */
    "experimentalDecorators": true,

    /* Advanced Options */
    "skipLibCheck": true,
    "forceConsistentCasingInFileNames": true,

    /* Strict Type-Checking Options */
    "strict": true,

    /* Additional Checks */
    "noFallthroughCasesInSwitch": true,
    "noImplicitReturns": true,
    "noPropertyAccessFromIndexSignature": true,
    "noUncheckedIndexedAccess": true,
    "noUnusedLocals": true,
    "noUnusedParameters": true,

    /* Incremental Build Options */
    "incremental": true,

    "baseUrl": "src",
    "noEmit": true
  }
}

Expected Result

The test TS code does not contain any ESLint errors.

Actual Result

The last line of the test TS code, dingus?.nested['hello'];, has this ESLint error:

["hello"] is better written in dot notation. eslint(typescript-eslint/dot-notation)

Additional Info

This GitHub repo contains this same test code and configs: https://github.com/kohlmannj/typescript-eslint-dot-notation-index-access-optional-chaining-bug

This is a reproduction of the issue that @eugene-stativka noted here: #3361 (comment)

Relates to:

Output from eslint --ext ".ts" src --debug

Note: You can rerun this command in https://github.com/kohlmannj/typescript-eslint-dot-notation-index-access-optional-chaining-bug with the yarn lint:debug script.

➜  typescript-eslint-dot-notation-index-access-optional-chaining-bug git:(main) ✗ yarn lint:debug
yarn run v1.22.10
$ yarn lint  --debug
$ eslint --ext ".ts" src --debug
  eslint:cli CLI args: [ '--ext', '.ts', 'src', '--debug' ] +0ms
  eslint:cli Running on files +4ms
  eslintrc:config-array-factory Loading JSON config file: /Users/joseph/Sites/kohlmannj/typescript-eslint-dot-notation-index-access-optional-chaining-bug/package.json +0ms
  eslintrc:ignore-pattern Create with: [ IgnorePattern { patterns: [ '/**/node_modules/*' ], basePath: '/Users/joseph/Sites/kohlmannj/typescript-eslint-dot-notation-index-access-optional-chaining-bug', loose: false } ] +0ms
  eslintrc:ignore-pattern   processed: { basePath: '/Users/joseph/Sites/kohlmannj/typescript-eslint-dot-notation-index-access-optional-chaining-bug', patterns: [ '/**/node_modules/*' ] } +1ms
  eslintrc:ignore-pattern Create with: [ IgnorePattern { patterns: [ '/**/node_modules/*' ], basePath: '/Users/joseph/Sites/kohlmannj/typescript-eslint-dot-notation-index-access-optional-chaining-bug', loose: false } ] +1ms
  eslintrc:ignore-pattern   processed: { basePath: '/Users/joseph/Sites/kohlmannj/typescript-eslint-dot-notation-index-access-optional-chaining-bug', patterns: [ '/**/node_modules/*' ] } +0ms
  eslint:file-enumerator Start to iterate files: [ 'src' ] +0ms
  eslint:file-enumerator Directory: /Users/joseph/Sites/kohlmannj/typescript-eslint-dot-notation-index-access-optional-chaining-bug/src +1ms
  eslint:file-enumerator Enter the directory: /Users/joseph/Sites/kohlmannj/typescript-eslint-dot-notation-index-access-optional-chaining-bug/src +0ms
  eslintrc:cascading-config-array-factory Load config files for /Users/joseph/Sites/kohlmannj/typescript-eslint-dot-notation-index-access-optional-chaining-bug/src. +0ms
  eslintrc:cascading-config-array-factory No cache found: /Users/joseph/Sites/kohlmannj/typescript-eslint-dot-notation-index-access-optional-chaining-bug/src. +0ms
  eslintrc:config-array-factory Config file not found on /Users/joseph/Sites/kohlmannj/typescript-eslint-dot-notation-index-access-optional-chaining-bug/src +5ms
  eslintrc:cascading-config-array-factory No cache found: /Users/joseph/Sites/kohlmannj/typescript-eslint-dot-notation-index-access-optional-chaining-bug. +1ms
  eslintrc:config-array-factory Loading legacy config file: /Users/joseph/Sites/kohlmannj/typescript-eslint-dot-notation-index-access-optional-chaining-bug/.eslintrc +0ms
  eslintrc:config-array-factory Config file found: /Users/joseph/Sites/kohlmannj/typescript-eslint-dot-notation-index-access-optional-chaining-bug/.eslintrc +19ms
  eslintrc:config-array-factory Loading parser "@typescript-eslint/parser" from /Users/joseph/Sites/kohlmannj/typescript-eslint-dot-notation-index-access-optional-chaining-bug/.eslintrc +1ms
  eslintrc:config-array-factory Loaded: @typescript-eslint/parser@4.26.1 (/Users/joseph/Sites/kohlmannj/typescript-eslint-dot-notation-index-access-optional-chaining-bug/node_modules/@typescript-eslint/parser/dist/index.js) +1ms
  eslintrc:config-array-factory Loading plugin "@typescript-eslint" from /Users/joseph/Sites/kohlmannj/typescript-eslint-dot-notation-index-access-optional-chaining-bug/.eslintrc +239ms
  eslintrc:config-array-factory Loaded: @typescript-eslint/eslint-plugin@4.26.1 (/Users/joseph/Sites/kohlmannj/typescript-eslint-dot-notation-index-access-optional-chaining-bug/node_modules/@typescript-eslint/eslint-plugin/dist/index.js) +1ms
  eslintrc:config-array-factory Plugin /Users/joseph/Sites/kohlmannj/typescript-eslint-dot-notation-index-access-optional-chaining-bug/node_modules/@typescript-eslint/eslint-plugin/dist/index.js loaded in: 152ms +152ms
  eslintrc:cascading-config-array-factory No cache found: /Users/joseph/Sites/kohlmannj. +413ms
  eslintrc:config-array-factory Config file not found on /Users/joseph/Sites/kohlmannj +0ms
  eslintrc:cascading-config-array-factory No cache found: /Users/joseph/Sites. +0ms
  eslintrc:config-array-factory Config file not found on /Users/joseph/Sites +0ms
  eslintrc:cascading-config-array-factory No cache found: /Users/joseph. +0ms
  eslintrc:cascading-config-array-factory Stop traversing because of considered root. +0ms
  eslintrc:cascading-config-array-factory Configuration was determined: ConfigArray(2) [ { type: 'config', name: 'DefaultIgnorePattern', filePath: '', criteria: null, env: undefined, globals: undefined, ignorePattern: IgnorePattern { patterns: [Array], basePath: '/Users/joseph/Sites/kohlmannj/typescript-eslint-dot-notation-index-access-optional-chaining-bug', loose: false }, noInlineConfig: undefined, parser: undefined, parserOptions: undefined, plugins: undefined, processor: undefined, reportUnusedDisableDirectives: undefined, root: undefined, rules: undefined, settings: undefined }, { type: 'config', name: '.eslintrc', filePath: '/Users/joseph/Sites/kohlmannj/typescript-eslint-dot-notation-index-access-optional-chaining-bug/.eslintrc', criteria: null, env: undefined, globals: undefined, ignorePattern: undefined, noInlineConfig: undefined, parser: { error: null, filePath: '/Users/joseph/Sites/kohlmannj/typescript-eslint-dot-notation-index-access-optional-chaining-bug/node_modules/@typescript-eslint/parser/dist/index.js', id: '@typescript-eslint/parser', importerName: '.eslintrc', importerPath: '/Users/joseph/Sites/kohlmannj/typescript-eslint-dot-notation-index-access-optional-chaining-bug/.eslintrc' }, parserOptions: { project: 'tsconfig.json' }, plugins: { '@typescript-eslint': [Object] }, processor: undefined, reportUnusedDisableDirectives: undefined, root: undefined, rules: { '@typescript-eslint/dot-notation': [Array] }, settings: undefined } ] on /Users/joseph/Sites/kohlmannj/typescript-eslint-dot-notation-index-access-optional-chaining-bug/src +2ms
  eslintrc:ignore-pattern Create with: [ IgnorePattern { patterns: [ '/**/node_modules/*' ], basePath: '/Users/joseph/Sites/kohlmannj/typescript-eslint-dot-notation-index-access-optional-chaining-bug', loose: false } ] +418ms
  eslintrc:ignore-pattern   processed: { basePath: '/Users/joseph/Sites/kohlmannj/typescript-eslint-dot-notation-index-access-optional-chaining-bug', patterns: [ '/**/node_modules/*' ] } +0ms
  eslintrc:ignore-pattern Check {
  filePath: '/Users/joseph/Sites/kohlmannj/typescript-eslint-dot-notation-index-access-optional-chaining-bug/src/index.ts',
  dot: false,
  relativePath: 'src/index.ts',
  result: false
} +1ms
  eslint:file-enumerator Yield: index.ts +418ms
  eslintrc:cascading-config-array-factory Load config files for /Users/joseph/Sites/kohlmannj/typescript-eslint-dot-notation-index-access-optional-chaining-bug/src. +2ms
  eslintrc:cascading-config-array-factory Cache hit: /Users/joseph/Sites/kohlmannj/typescript-eslint-dot-notation-index-access-optional-chaining-bug/src. +0ms
  eslint:cli-engine Lint /Users/joseph/Sites/kohlmannj/typescript-eslint-dot-notation-index-access-optional-chaining-bug/src/index.ts +0ms
  eslint:linter Linting code for /Users/joseph/Sites/kohlmannj/typescript-eslint-dot-notation-index-access-optional-chaining-bug/src/index.ts (pass 1) +0ms
  eslint:linter Verify +0ms
  eslint:linter With ConfigArray: /Users/joseph/Sites/kohlmannj/typescript-eslint-dot-notation-index-access-optional-chaining-bug/src/index.ts +0ms
  eslint:linter Generating fixed text for /Users/joseph/Sites/kohlmannj/typescript-eslint-dot-notation-index-access-optional-chaining-bug/src/index.ts (pass 1) +639ms
  eslint:source-code-fixer Applying fixes +0ms
  eslint:source-code-fixer shouldFix parameter was false, not attempting fixes +0ms
  eslint:file-enumerator Leave the directory: /Users/joseph/Sites/kohlmannj/typescript-eslint-dot-notation-index-access-optional-chaining-bug/src +639ms
  eslint:file-enumerator Complete iterating files: ["src"] +0ms
  eslint:cli-engine Linting complete in: 1058ms +639ms

/Users/joseph/Sites/kohlmannj/typescript-eslint-dot-notation-index-access-optional-chaining-bug/src/index.ts
  14:16  error  ["hello"] is better written in dot notation  @typescript-eslint/dot-notation

✖ 1 problem (1 error, 0 warnings)
  1 error and 0 warnings potentially fixable with the `--fix` option.

error Command failed with exit code 1.
info Visit https://yarnpkg.com/en/docs/cli/run for documentation about this command.
error Command failed with exit code 1.
info Visit https://yarnpkg.com/en/docs/cli/run for documentation about this command.
➜  typescript-eslint-dot-notation-index-access-optional-chaining-bug git:(main) ✗

Versions

package	version
`@typescript-eslint/eslint-plugin`	`4.26.1`
`@typescript-eslint/parser`	`4.26.1`
`TypeScript`	`4.3.2`
`ESLint`	`7.28.0`
`node`	`14.5.0`

The text was updated successfully, but these errors were encountered:

bradzacher · 2021-06-10T19:17:03Z

the problem here is that the type of dingus?.nested is reported by TS as Nested | undefined.
So TS returns nothing for this call:

typescript-eslint/packages/eslint-plugin/src/rules/dot-notation.ts

Lines 113 to 116 in 79b510c

    
           const indexType = typeChecker.getIndexTypeOfType( 
        
             objectType, 
        
             ts.IndexKind.String, 
        
           );

djcsdy · 2021-08-05T08:55:35Z

I'm working on a fix for this.

closes typescript-eslint#3510

…ing (#3711) closes #3510

kohlmannj added package: eslint-plugin Issues related to @typescript-eslint/eslint-plugin triage Waiting for maintainers to take a look labels Jun 9, 2021

bradzacher added bug Something isn't working and removed triage Waiting for maintainers to take a look labels Jun 10, 2021

djcsdy added a commit to djcsdy/typescript-eslint that referenced this issue Aug 5, 2021

fix(eslint-plugin): dot-notation: false positive with optional chaining

7756865

closes typescript-eslint#3510

djcsdy mentioned this issue Aug 5, 2021

fix(eslint-plugin): [dot-notation] false positive with optional chaining #3711

Merged

bradzacher closed this as completed in #3711 Aug 30, 2021

bradzacher pushed a commit that referenced this issue Aug 30, 2021

fix(eslint-plugin): [dot-notation] false positive with optional chain…

c19fc6e

…ing (#3711) closes #3510

github-actions bot locked as resolved and limited conversation to collaborators Sep 30, 2021

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[dot-notation] False positive with optional chaining and `allowIndexSignaturePropertyAccess: true` #3510

[dot-notation] False positive with optional chaining and `allowIndexSignaturePropertyAccess: true` #3510

kohlmannj commented Jun 9, 2021 •

edited

bradzacher commented Jun 10, 2021

djcsdy commented Aug 5, 2021

[dot-notation] False positive with optional chaining and allowIndexSignaturePropertyAccess: true #3510

[dot-notation] False positive with optional chaining and allowIndexSignaturePropertyAccess: true #3510

Comments

kohlmannj commented Jun 9, 2021 • edited

bradzacher commented Jun 10, 2021

djcsdy commented Aug 5, 2021

[dot-notation] False positive with optional chaining and `allowIndexSignaturePropertyAccess: true` #3510

[dot-notation] False positive with optional chaining and `allowIndexSignaturePropertyAccess: true` #3510

kohlmannj commented Jun 9, 2021 •

edited