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📄 no-for-in-array.ts

📊 Analysis Summary

Metric	Count
🔧 Functions	3
📦 Imports	4

📚 Table of Contents

• Imports
• Functions

🛠️ File Location:

📂 packages/eslint-plugin/src/rules/no-for-in-array.ts

📦 Imports

Name	Source
createRule	../util
getConstrainedTypeAtLocation	../util
getParserServices	../util
getForStatementHeadLoc	../util/getForStatementHeadLoc

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Functions

isArrayLike(checker: ts.TypeChecker, type: ts.Type): boolean

Code

function isArrayLike(checker: ts.TypeChecker, type: ts.Type): boolean {
  return isTypeRecurser(
    type,
    t => t.getNumberIndexType() != null && hasArrayishLength(checker, t),
  );
}

• Parameters:
• checker: ts.TypeChecker
• type: ts.Type
• Return Type: boolean
• Calls:
• isTypeRecurser
• t.getNumberIndexType
• hasArrayishLength

hasArrayishLength(checker: ts.TypeChecker, type: ts.Type): boolean

Code

function hasArrayishLength(checker: ts.TypeChecker, type: ts.Type): boolean {
  const lengthProperty = type.getProperty('length');

  if (lengthProperty == null) {
    return false;
  }

  return tsutils.isTypeFlagSet(
    checker.getTypeOfSymbol(lengthProperty),
    ts.TypeFlags.NumberLike,
  );
}

• Parameters:
• checker: ts.TypeChecker
• type: ts.Type
• Return Type: boolean
• Calls:
• type.getProperty
• tsutils.isTypeFlagSet
• checker.getTypeOfSymbol

isTypeRecurser(type: ts.Type, predicate: (t: ts.Type) => boolean): boolean

Code

function isTypeRecurser(
  type: ts.Type,
  predicate: (t: ts.Type) => boolean,
): boolean {
  if (type.isUnionOrIntersection()) {
    return type.types.some(t => isTypeRecurser(t, predicate));
  }

  return predicate(type);
}

• Parameters:
• type: ts.Type
• predicate: (t: ts.Type) => boolean
• Return Type: boolean
• Calls:
• type.isUnionOrIntersection
• type.types.some
• isTypeRecurser
• predicate

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