| 1 | /** |
| 2 | * Copyright (c) Meta Platforms, Inc. and affiliates. |
| 3 | * |
| 4 | * This source code is licensed under the MIT license found in the |
| 5 | * LICENSE file in the root directory of this source tree. |
| 6 | */ |
| 7 | |
| 8 | /** |
| 9 | * Our philosophy for linting is that lints should be very high-signal: |
| 10 | * - Error, don't warn. If it's worth mentioning it's worth fixing. |
| 11 | * - Enable rules that consistently identify real problems. If we frequently would have to |
| 12 | * disable the rule due to false positives, it isn't high-signal. |
| 13 | * - Enable rules that help improve consistent style (to avoid code review about style rather |
| 14 | * than substance). |
| 15 | */ |
| 16 | module.exports = { |
| 17 | extends: ["eslint:recommended", "plugin:@typescript-eslint/recommended"], |
| 18 | rules: { |
| 19 | /* |
| 20 | * We prefer using const where variables are not reassigned, but occassional mistakes |
| 21 | * aren't a major issue |
| 22 | */ |
| 23 | "prefer-const": "off", |
| 24 | |
| 25 | // Not valuable enough to enable |
| 26 | "no-useless-escape": "off", |
| 27 | |
| 28 | /* |
| 29 | * There are valid use cases for loops with constant conditions where the body contains the |
| 30 | * break |
| 31 | */ |
| 32 | "no-constant-condition": "off", |
| 33 | |
| 34 | // eslint only knows about builtin control flow (eg throw, return, break) and not custom ones |
| 35 | // like invariant. |
| 36 | "no-fallthrough": "off", |
| 37 | |
| 38 | /* |
| 39 | * Low-value: this fires even for declarations that capture references which wouldn't be as |
| 40 | * obvious if the declaration was lifted to the parent root |
| 41 | */ |
| 42 | "no-inner-declarations": "off", |
| 43 | |
| 44 | "multiline-comment-style": ["error", "starred-block"], |
| 45 | |
| 46 | /** |
| 47 | * We sometimes need to check for control characters in regexes for things like preserving input |
| 48 | * strings |
| 49 | */ |
| 50 | "no-control-regex": "off", |
| 51 | |
| 52 | "@typescript-eslint/no-empty-function": "off", |
| 53 | |
| 54 | /* |
| 55 | * Explicitly casting to/through any is sometimes required, often for error messages to |
| 56 | * assertExhaustive() |
| 57 | */ |
| 58 | "@typescript-eslint/no-explicit-any": "off", |
| 59 | |
| 60 | /* |
| 61 | * We use non-null assertions carefully. Ideally, there would be a TS option to codegen |
| 62 | * a non-null check at the assertion site. |
| 63 | */ |
| 64 | "@typescript-eslint/no-non-null-assertion": "off", |
| 65 | |
| 66 | // Being explicit provides value in cases where inference may later change |
| 67 | "@typescript-eslint/no-inferrable-types": "off", |
| 68 | "@typescript-eslint/explicit-function-return-type": "error", |
| 69 | |
| 70 | /* |
| 71 | * Unused variables are frequently a bug. Prefix unused variables with an _ to fix, but note |
| 72 | * that eslint won't warn you that an underscore prefixed variable is used and that the prefix |
| 73 | * should be dropped. |
| 74 | */ |
| 75 | "@typescript-eslint/no-unused-vars": [ |
| 76 | "error", |
| 77 | { |
| 78 | argsIgnorePattern: "^_", |
| 79 | varsIgnorePattern: "^_", |
| 80 | caughtErrorsIgnorePattern: "^_", |
| 81 | }, |
| 82 | ], |
| 83 | |
| 84 | // Consider enabling for consistency. Ideally violations could be auto-fixed. |
| 85 | "@typescript-eslint/consistent-generic-constructors": [ |
| 86 | "off", |
| 87 | "constructor", |
| 88 | ], |
| 89 | "@typescript-eslint/array-type": ["error", { default: "generic" }], |
| 90 | "@typescript-eslint/triple-slash-reference": "off", |
| 91 | "@typescript-eslint/no-var-requires": "off", |
| 92 | }, |
| 93 | parser: "@typescript-eslint/parser", |
| 94 | plugins: ["@typescript-eslint"], |
| 95 | root: true, |
| 96 | ignorePatterns: ["**/__tests__/**/*", "**/*.d.ts", "**/dist/**/*"], |
| 97 | env: { |
| 98 | node: true, |
| 99 | }, |
| 100 | /* |
| 101 | * If rules need to be disabled then the rule is insufficiently high signal |
| 102 | * and should be diasbled altogether or customized (in either case via a standalone PR) |
| 103 | */ |
| 104 | noInlineConfig: true, |
| 105 | reportUnusedDisableDirectives: true, |
| 106 | }; |