Rules
Custom ESLint Rules
Custom ESLint rules for catching unsafe patterns and enforcing consistent code style across JavaScript and TypeScript projects.
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Dotenv Suite
Require every value in .env and .env.sample files to be wrapped in double quotes with the registerDotenvSuite conformance suite.
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Frontmatter Suite
Require valid frontmatter fields on every Markdown and MDX content file with the registerFrontmatterSuite conformance suite.
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Link Suite
Verify that internal documentation links and anchors resolve to real targets with the registerLinkSuite conformance suite.
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Markdown Table Suite
Require documentation tables to match canonical MarkdownTable output with the registerMarkdownTableSuite conformance suite.
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No Assign Then Return
Disallow assigning to a const variable and immediately returning it when the value can be returned directly without the intermediate binding.
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No Await In Loop
Disallow await inside loops so sequential async calls that could be parallelized with Promise.all are caught early during linting.
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No Boolean Var For If
Disallow extracting a multi-condition boolean into a single-use variable when the condition can be inlined in the next if-statement.
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No Bracket Assignment
Disallow bracket notation assignment on objects and encourage Reflect.set for dynamic property writes to keep mutation sites explicit.
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No Bracket Method Call
Disallow calling methods via bracket notation with a static string key when standard dot notation is available and more readable.
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No Catch Unknown Annotation
Disallow redundant unknown type annotations on catch clause variables because TypeScript already defaults the binding to unknown.
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No Complex Arrow Concise
Require arrow functions with complex concise bodies to use an explicit block body so the return value is always visually distinct.
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No Default Export Declaration
Disallow attaching function or class declarations to export default so every exported symbol has an explicit and searchable name.
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No Destructuring
Disallow destructuring patterns in callbacks, for-of loops, function parameters, variable declarations, and assignment expressions.
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No Explicit Any
Disallow usage of the any type and require unknown with type guards or a specific named type to maintain full type-level safety.
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No Implicit Boolean
Require explicit boolean comparisons instead of relying on truthy/falsy coercion in conditions for unambiguous control flow intent.
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No Inline Type Annotation
Disallow inline type annotations in code files and require named type aliases imported from dedicated definition files instead.
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No Logger.dev
Disallow Logger.dev calls in production code so dev-only logging statements are caught before release and never reach shipped builds.
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No Multiline Strings
Disallow multiline string content including backslash continuation, visual newlines in template literals, and internal escape sequences.
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No Numeric Literals
Disallow binary, octal, and hexadecimal numeric literal forms and require parseInt with an explicit radix argument for readable numbers.
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No Optional Chaining
Disallow the optional chaining operator so null and undefined checks are explicit and the intended handling of absent values is visible.
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No Raw Text in Code
Disallow unwrapped text inside code JSX elements to prevent MDX from parsing special characters as JSX tags inside inline code spans.
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No Regex Literal Flags
Disallow flags on regex literals so shared patterns stay reusable and callers add flags at the call site via new RegExp.
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No Regex Literals
Disallow inline regex literal expressions so patterns are centralized in a shared patterns file and reusable across the codebase.
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No Rest Params
Disallow rest parameters in function signatures so every parameter is listed explicitly and callers can see the full expected argument list.
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No Script URL
Disallow javascript colon URLs except for explicitly allowed patterns such as javascript void zero to prevent cross-site scripting.
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No Shared Type Import
Disallow importing shared type files in code files to enforce type layering where shared types flow through domain type files.
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No Template Curly in String
Disallow template literal placeholder syntax in regular strings so missing backticks are caught before the expression appears literally in output.
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No Ternary in Template Literal
Disallow ternary expressions inside template literals to keep template strings readable and encourage extracting logic into variables.
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No Use Before Define
Disallow use of variables, constants, functions, classes, and types before they are defined to enforce top-down declaration order.
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Require Bracket Property Access
Require bracket notation instead of dot notation for property access on project-defined plain objects to keep access patterns consistent.
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Require Explicit Return
Require an explicit return statement at the end of void function bodies so every function signals its exit point for consistent flow.
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Require Hash Private
Require #hash notation for private class members instead of the private keyword so privacy is enforced at the runtime language level.
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Require Import Order
Require 6-group import ordering with regular imports first (Node built-ins, third-party, local) then type imports (Node built-ins, third-party, local).
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Require JSDoc Body
Require a body paragraph in JSDoc blocks that explains why the declaration exists rather than restating the function or class name.
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Require JSDoc Hierarchy
Require JSDoc summary lines to follow the hierarchy chain derived from the file path and method name for searchable documentation.
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Require JSDoc Param Alignment
Require vertical alignment of param types, names, and dashes in JSDoc blocks so multi-parameter signatures stay visually consistent.
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Require JSDoc Param Name
Require param descriptions in JSDoc blocks to match the parameter name with the first letter capitalized and a trailing period.
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Require JSDoc Presence
Require a leading JSDoc block on every documentable symbol so no class, function, method, or property ships undocumented.
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Require JSDoc Private
Require a private tag in JSDoc blocks for private class members to keep documentation consistent with TypeScript access modifiers.
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Require JSDoc Returns
Require every @returns tag in JSDoc blocks to contain only a type in braces, with no trailing description after the type annotation.
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Require JSDoc Since
Require a @since tag in every JSDoc block and validate its value as a semver version or UNRELEASED to track API introduction dates.
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Require JSDoc Tag Order
Require JSDoc tags to follow the canonical order with exactly one blank line between adjacent tag groups for consistent documentation.
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Require Kebab Case Filename
Require kebab-case file names for TypeScript source files so filenames stay consistent, URL-safe, and free of case-sensitivity issues.
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Require Multiline Condition Groups
Require expanded formatting for parenthesized groups in mixed-operator logical expressions so each condition group starts on its own line.
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Require Multiline Conditions
Require each operand to be on its own line when a logical expression exceeds the allowed inline count for readable condition chains.
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Require Naming Convention
Enforce context-aware naming conventions for identifiers based on their declaration type including camelCase, PascalCase, and UPPER_SNAKE.
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Require Node Protocol
Require the node: protocol when importing Node.js built-in modules so built-in imports are visually distinct from third-party packages.
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Require Padding Lines
Require blank lines between specific statement patterns for improved readability such as exit code before return and before loops.
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Require Ternary Parens
Require parenthesized condition in ternary expressions so the test clause is visually separated from the consequent and alternate branches.
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Require Type Naming
Require type alias names in definition files to start with the class name prefix derived from the file path for consistent naming.
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Require Undefined Init
Require explicit undefined initializer when declaring variables without a value so uninitialized state is always visible in the source.
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Switch Case Blocks
Require every non-empty switch case to wrap its body in a block so declarations stay scoped and branches stay independent.
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Terminology Suite
Validate Terminology glossary components against a source glossary page with the registerTerminologySuite conformance suite.
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Type Declarations Suite
Audit TypeScript declaration mirror files against their sources for structure, ordering, naming, and coverage with registerTypeDeclarationSuite.
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Vitest Conformance Kit
Importable Vitest conformance suites that hold your project's docs and types to the same conventions Nova enforces on itself.
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Workspace Rules
How Nova governs workspaces using roles, policies, and field handling rules that determine what each package.json recipe enforces.
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