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📄 array-type.ts

📊 Analysis Summary

Metric Count
🔧 Functions 3
📦 Imports 4
📊 Variables & Constants 18
📑 Type Aliases 3

📚 Table of Contents

🛠️ File Location:

📂 packages/eslint-plugin/src/rules/array-type.ts

📦 Imports

Name Source
TSESTree @typescript-eslint/utils
AST_NODE_TYPES @typescript-eslint/utils
createRule ../util
isParenthesized ../util

Variables & Constants

Name Type Kind Value Exported
defaultOption any const options.default ✗
readonlyOption any const options.readonly ?? defaultOption ✗
isReadonly boolean const `node.parent.type === AST_NODE_TYPES.TSTypeOperator &&
node.parent.operator === 'readonly'` ✗
currentOption any const isReadonly ? readonlyOption : defaultOption ✗
messageId "errorStringGeneric" | "errorStringGenericSimple" const `currentOption === 'generic'
? 'errorStringGeneric'
: 'errorStringGenericSimple'` ✗
errorNode any const isReadonly ? node.parent : node ✗
typeNode any const node.elementType ✗
arrayType "ReadonlyArray" | "Array" const isReadonly ? 'ReadonlyArray' : 'Array' ✗
isReadonlyWithGenericArrayType boolean const `node.typeName.name === 'Readonly' &&
node.typeArguments?.params[0].type === AST_NODE_TYPES.TSArrayType` ✗
isReadonlyArrayType boolean const `node.typeName.name === 'ReadonlyArray'
isReadonlyWithGenericArrayType` ✗
currentOption any const `isReadonlyArrayType
? readonlyOption
: defaultOption` ✗
readonlyPrefix "" | "readonly " const isReadonlyArrayType ? 'readonly ' : '' ✗
typeParams any const node.typeArguments?.params ✗
messageId "errorStringArray" | "errorStringArrayReadonly" | "errorStringArraySimple" | "errorStringArraySimpleReadonly" const `currentOption === 'array'
? isReadonlyWithGenericArrayType
? 'errorStringArrayReadonly'
: 'errorStringArray'
: isReadonlyArrayType && node.typeName.name !== 'ReadonlyArray'
? 'errorStringArraySimpleReadonly'
: 'errorStringArraySimple'` ✗
type any const typeParams[0] ✗
parentParens boolean const `readonlyPrefix &&
node.parent.type === AST_NODE_TYPES.TSArrayType &&
!isParenthesized(node.parent.elementType, context.sourceCode)` ✗
start string const ``${parentParens ? '(' : ''}${readonlyPrefix}${
typeParens ? '(' : ''
}`` ✗
end string const ${typeParens ? ')' : ''}${isReadonlyWithGenericArrayType ? '' : `[]`}${parentParens ? ')' : ''} ✗

Functions

isSimpleType(node: TSESTree.Node): boolean

Code 
function isSimpleType(node: TSESTree.Node): boolean {
  switch (node.type) {
    case AST_NODE_TYPES.Identifier:
    case AST_NODE_TYPES.TSAnyKeyword:
    case AST_NODE_TYPES.TSBooleanKeyword:
    case AST_NODE_TYPES.TSNeverKeyword:
    case AST_NODE_TYPES.TSNumberKeyword:
    case AST_NODE_TYPES.TSBigIntKeyword:
    case AST_NODE_TYPES.TSObjectKeyword:
    case AST_NODE_TYPES.TSStringKeyword:
    case AST_NODE_TYPES.TSSymbolKeyword:
    case AST_NODE_TYPES.TSUnknownKeyword:
    case AST_NODE_TYPES.TSVoidKeyword:
    case AST_NODE_TYPES.TSNullKeyword:
    case AST_NODE_TYPES.TSArrayType:
    case AST_NODE_TYPES.TSUndefinedKeyword:
    case AST_NODE_TYPES.TSThisType:
    case AST_NODE_TYPES.TSQualifiedName:
      return true;
    case AST_NODE_TYPES.TSTypeReference:
      if (
        node.typeName.type === AST_NODE_TYPES.Identifier &&
        node.typeName.name === 'Array'
      ) {
        if (!node.typeArguments) {
          return true;
        }
        if (node.typeArguments.params.length === 1) {
          return isSimpleType(node.typeArguments.params[0]);
        }
      } else {
        if (node.typeArguments) {
          return false;
        }
        return isSimpleType(node.typeName);
      }
      return false;
    default:
      return false;
  }
}

  • JSDoc: 

    /**
 * Check whatever node can be considered as simple
 * @param node the node to be evaluated.
 */

  • Parameters:

  • node: TSESTree.Node
  • Return Type: boolean
  • Calls:
  • isSimpleType

typeNeedsParentheses(node: TSESTree.Node): boolean

Code 
function typeNeedsParentheses(node: TSESTree.Node): boolean {
  switch (node.type) {
    case AST_NODE_TYPES.TSTypeReference:
      return typeNeedsParentheses(node.typeName);
    case AST_NODE_TYPES.TSUnionType:
    case AST_NODE_TYPES.TSFunctionType:
    case AST_NODE_TYPES.TSIntersectionType:
    case AST_NODE_TYPES.TSTypeOperator:
    case AST_NODE_TYPES.TSInferType:
    case AST_NODE_TYPES.TSConstructorType:
    case AST_NODE_TYPES.TSConditionalType:
      return true;
    case AST_NODE_TYPES.Identifier:
      return node.name === 'ReadonlyArray';
    default:
      return false;
  }
}

  • JSDoc: 

    /**
 * Check if node needs parentheses
 * @param node the node to be evaluated.
 */

  • Parameters:

  • node: TSESTree.Node
  • Return Type: boolean
  • Calls:
  • typeNeedsParentheses

getMessageType(node: TSESTree.Node): string

Code 
function getMessageType(node: TSESTree.Node): string {
      if (isSimpleType(node)) {
        return context.sourceCode.getText(node);
      }
      return 'T';
    }

  • JSDoc: 

    /**
     * @param node the node to be evaluated.
     */

  • Parameters:

  • node: TSESTree.Node
  • Return Type: string
  • Calls:
  • isSimpleType
  • context.sourceCode.getText

Type Aliases

OptionString

type OptionString = 'array' | 'array-simple' | 'generic';

Options

type Options = [
  {
    default: OptionString;
    readonly?: OptionString;
  },
];

MessageIds

type MessageIds = | 'errorStringArray'
  | 'errorStringArrayReadonly'
  | 'errorStringArraySimple'
  | 'errorStringArraySimpleReadonly'
  | 'errorStringGeneric'
  | 'errorStringGenericSimple';