.eslintrc.json

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        "resize": false,
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        "server_events_dispatch": false,
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        "settings_users": false,
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        "typeahead_helper": false,
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        "unread": false,
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        "upgrade": false,
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        "user_pill": false,
        "user_search": false,
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        "widgetize": false,
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        "zform": false,
        "zxcvbn": false
    },
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        "eslint-plugin-empty-returns"
    ],
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        "array-callback-return": "error",
        "array-bracket-spacing": "error",
        "arrow-spacing": [ "error", { "before": true, "after": true } ],
        "block-scoped-var": "error",
        "brace-style": [ "error", "1tbs", { "allowSingleLine": true } ],
        "camelcase": "off",
        "comma-dangle": [ "error",
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                "arrays": "always-multiline",
                "objects": "always-multiline",
                "imports": "always-multiline",
                "exports": "always-multiline",
                "functions": "never"
            }
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        "comma-spacing": [ "error",
            {
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                "after": true
            }
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        "complexity": [ "off", 4 ],
        "curly": "error",
        "dot-notation": [ "error", { "allowKeywords": true } ],
        "empty-returns/main": "error",
        "eol-last": [ "error", "always" ],
        "eqeqeq": "error",
        "func-style": [ "off", "expression" ],
        "guard-for-in": "error",
        "indent": ["error", 4, {
            "ArrayExpression": "first",
            "ObjectExpression": "first",
            "SwitchCase": 0,
            "CallExpression": {"arguments": "first"},
            "FunctionExpression": {"parameters": "first"},
            "FunctionDeclaration": {"parameters": "first"}
        }],
        "key-spacing": [ "error",
            {
                "beforeColon": false,
                "afterColon": true
            }
        ],
        "keyword-spacing": [ "error",
            {
                "before": true,
                "after": true,
                "overrides": {
                    "return": { "after": true },
                    "throw": { "after": true },
                    "case": { "after": true }
                }
            }
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        "max-depth": [ "off", 4 ],
        "max-len": [ "error", 100, 2,
            {
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                "ignoreComments": false,
                "ignoreRegExpLiterals": true,
                "ignoreStrings": true,
                "ignoreTemplateLiterals": true
            }
        ],
        "max-params": [ "off", 3 ],
        "max-statements": [ "off", 10 ],
        "new-cap": [ "error",
            {
                "newIsCap": true,
                "capIsNew": false
            }
        ],
        "new-parens": "error",
        "newline-per-chained-call": "off",
        "no-alert": "error",
        "no-array-constructor": "error",
        "no-bitwise": "error",
        "no-caller": "error",
        "no-case-declarations": "error",
        "no-catch-shadow": "error",
        "no-console": "off",
        "no-const-assign": "error",
        "no-control-regex": "error",
        "no-debugger": "error",
        "no-delete-var": "error",
        "no-div-regex": "error",
        "no-dupe-class-members": "error",
        "no-dupe-keys": "error",
        "no-duplicate-imports": "error",
        "no-else-return": "error",
        "no-empty": "error",
        "no-empty-character-class": "error",
        "no-eq-null": "error",
        "no-eval": "error",
        "no-ex-assign": "error",
        "no-extra-parens": ["error", "all"],
        "no-extra-semi": "error",
        "no-fallthrough": "error",
        "no-floating-decimal": "error",
        "no-func-assign": "error",
        "no-implied-eval": "error",
        "no-iterator": "error",
        "no-label-var": "error",
        "no-labels": "error",
        "no-loop-func": "error",
        "no-mixed-requires": [ "off", false ],
        "no-multi-str": "error",
        "no-native-reassign": "error",
        "no-nested-ternary": "off",
        "no-new-func": "error",
        "no-new-object": "error",
        "no-new-wrappers": "error",
        "no-obj-calls": "error",
        "no-octal": "error",
        "no-octal-escape": "error",
        "no-param-reassign": "off",
        "no-plusplus": "error",
        "no-proto": "error",
        "no-redeclare": "error",
        "no-regex-spaces": "error",
        "no-restricted-syntax": "off",
        "no-return-assign": "error",
        "no-script-url": "error",
        "no-self-compare": "error",
        "no-shadow": "off",
        "no-sync": "error",
        "no-ternary": "off",
        "no-trailing-spaces": "error",
        "no-undef": "error",
        "no-undef-init": "error",
        "no-underscore-dangle": "off",
        "no-unneeded-ternary": [ "error", { "defaultAssignment": false } ],
        "no-unreachable": "error",
        "no-unused-expressions": "error",
        "no-unused-vars": [ "error",
            {
                "vars": "local",
                "args": "after-used",
                "varsIgnorePattern": "print_elapsed_time|check_duplicate_ids"
            }
        ],
        "no-use-before-define": "error",
        "no-useless-constructor": "error",
        // The Zulip codebase complies partially with the "no-useless-escape"
        // rule; only regex expressions haven't been updated yet.
        // Updated regex expressions are currently being tested in casper
        // files and will decide about a potential future enforcement of this rule.
        "no-useless-escape": "off",
        "no-var": "error",
        "space-unary-ops": "error",
        "no-whitespace-before-property": "error",
        "no-with": "error",
        "one-var": [ "error", "never" ],
        "padded-blocks": "off",
        "prefer-const": [ "error",
            {
                "destructuring": "any",
                "ignoreReadBeforeAssign": true
            }
        ],
        "quote-props": [ "error", "as-needed",
            {
                "keywords": false,
                "unnecessary": true,
                "numbers": false
            }
        ],
        "quotes": [ "off", "single" ],
        "radix": "error",
        "semi": "error",
        "semi-spacing": ["error", {"before": false, "after": true}],
        "sort-imports": "error",
        "space-before-blocks": "error",
        "space-before-function-paren": [ "error",
            {
                "anonymous": "always",
                "named": "never",
                "asyncArrow": "always"
            }
        ],
        "space-in-parens": "error",
        "space-infix-ops": "error",
        "spaced-comment": "off",
        "strict": "off",
        "template-curly-spacing": "error",
        "unnecessary-strict": "off",
        "use-isnan": "error",
        "valid-typeof": [ "error", { "requireStringLiterals": true } ],
        "wrap-iife": [ "error", "outside", { "functionPrototypeMethods": false } ],
        "wrap-regex": "off",
        "yoda": "error"
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                "frontend_tests/casper_tests/*.js",
                "frontend_tests/casper_lib/*.js"
            ],
            "rules": {
                "no-var": "off" // PhantomJS doesn’t support let, const
            }
        },
        {
            "files": ["**/*.ts"],
            "parser": "@typescript-eslint/parser",
            "parserOptions": {
                "project": "tsconfig.json"
            },
            "plugins": ["@typescript-eslint"],
            "rules": {
                // Disable base rule to avoid conflict
                "empty-returns/main": "off",
                "indent": "off",
                "func-call-spacing": "off",
                "no-magic-numbers": "off",
                "semi": "off",
                "no-unused-vars": "off",
                "no-useless-constructor": "off",

                "@typescript-eslint/adjacent-overload-signatures": "error",
                "@typescript-eslint/array-type": "error",
                "@typescript-eslint/await-thenable": "error",
                "@typescript-eslint/ban-types": "error",
                "@typescript-eslint/ban-ts-ignore": "off",
                "@typescript-eslint/camelcase": "off",
                "@typescript-eslint/class-name-casing": "error",
                "@typescript-eslint/consistent-type-assertions": "error",
                "@typescript-eslint/explicit-function-return-type": ["error", { "allowExpressions": true }],
                "@typescript-eslint/explicit-member-accessibility": "off",
                "@typescript-eslint/func-call-spacing": "error",
                "@typescript-eslint/generic-type-naming": "off",
                "@typescript-eslint/indent": "error",
                "@typescript-eslint/interface-name-prefix": "off",
                "@typescript-eslint/member-delimiter-style": "error",
                "@typescript-eslint/member-naming": ["error", { "private": "^_" } ],
                "@typescript-eslint/member-ordering": "error",
                "@typescript-eslint/no-array-constructor": "error",
                "@typescript-eslint/no-empty-interface": "error",
                "@typescript-eslint/no-explicit-any": "off",
                "@typescript-eslint/no-extraneous-class": "error",
                "@typescript-eslint/no-for-in-array": "off",
                "@typescript-eslint/no-inferrable-types": "error",
                "@typescript-eslint/no-magic-numbers": "off",
                "@typescript-eslint/no-misused-new": "error",
                "@typescript-eslint/no-namespace": "error",
                "@typescript-eslint/no-non-null-assertion": "off",
                "@typescript-eslint/no-parameter-properties": "error",
                "@typescript-eslint/no-require-imports": "off",
                "@typescript-eslint/no-this-alias": "off",
                "@typescript-eslint/no-type-alias": "off",
                "@typescript-eslint/no-unnecessary-qualifier": "error",
                "@typescript-eslint/no-unnecessary-type-assertion": "error",
                "@typescript-eslint/no-unused-vars": ["error", { "varsIgnorePattern": "^_" } ],
                "@typescript-eslint/no-use-before-define": "error",
                "@typescript-eslint/no-useless-constructor": "error",
                "@typescript-eslint/no-var-requires": "off",
                "@typescript-eslint/prefer-for-of": "off",
                "@typescript-eslint/prefer-function-type": "off",
                "@typescript-eslint/prefer-includes": "error",
                "@typescript-eslint/prefer-interface": "off",
                "@typescript-eslint/prefer-namespace-keyword": "error",
                "@typescript-eslint/prefer-regexp-exec": "error",
                "@typescript-eslint/prefer-string-starts-ends-with": "error",
                "@typescript-eslint/promise-function-async": "error",
                "@typescript-eslint/restrict-plus-operands": "off",
                "@typescript-eslint/semi": "error",
                "@typescript-eslint/triple-slash-reference": "error",
                "@typescript-eslint/type-annotation-spacing": "error",
                "@typescript-eslint/unbound-method": "off",
                "@typescript-eslint/unified-signatures": "error"
            }
        }
    ]
}