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📄 getConstraintInfo.ts

📊 Analysis Summary

Metric	Count
🔧 Functions	1
📐 Interfaces	3
📑 Type Aliases	1

📚 Table of Contents

• Functions
• Interfaces
• Type Aliases

🛠️ File Location:

📂 packages/eslint-plugin/src/util/getConstraintInfo.ts

Functions

getConstraintInfo(checker: ts.TypeChecker, type: ts.Type): ConstraintTypeInfo

Code

export function getConstraintInfo(
  checker: ts.TypeChecker,
  type: ts.Type,
): ConstraintTypeInfo {
  if (tsutils.isTypeParameter(type)) {
    const constraintType = checker.getBaseConstraintOfType(type);
    return {
      constraintType,
      isTypeParameter: true,
    };
  }
  return {
    constraintType: type,
    isTypeParameter: false,
  };
}

• JSDoc:

  /**
   * Returns whether the type is a generic and what its constraint is.
   *
   * If the type is not a generic, `isTypeParameter` will be `false`, and
   * `constraintType` will be the same as the input type.
   *
   * If the type is a generic, and it is constrained, `isTypeParameter` will be
   * `true`, and `constraintType` will be the constraint type.
   *
   * If the type is a generic, but it is not constrained, `constraintType` will be
   * `undefined` (rather than an `unknown` type), due to https://github.com/microsoft/TypeScript/issues/60475
   *
   * Successor to {@link getConstrainedTypeAtLocation} due to https://github.com/typescript-eslint/typescript-eslint/issues/10438
   *
   * This is considered internal since it is unstable for now and may have breaking changes at any time.
   * Use at your own risk.
   *
   * @internal
   *
   */
  

• Parameters:

• checker: ts.TypeChecker
• type: ts.Type
• Return Type: ConstraintTypeInfo
• Calls:
• tsutils.isTypeParameter
• checker.getBaseConstraintOfType

---

Interfaces

ConstraintTypeInfoUnconstrained

Interface Code

export interface ConstraintTypeInfoUnconstrained {
  constraintType: undefined;
  isTypeParameter: true;
}

Properties

Name	Type	Optional	Description
constraintType	undefined	✗
isTypeParameter	true	✗

ConstraintTypeInfoConstrained

Interface Code

export interface ConstraintTypeInfoConstrained {
  constraintType: ts.Type;
  isTypeParameter: true;
}

Properties

Name	Type	Optional	Description
constraintType	ts.Type	✗
isTypeParameter	true	✗

ConstraintTypeInfoNonGeneric

Interface Code

export interface ConstraintTypeInfoNonGeneric {
  constraintType: ts.Type;
  isTypeParameter: false;
}

Properties

Name	Type	Optional	Description
constraintType	ts.Type	✗
isTypeParameter	false	✗

---

Type Aliases

ConstraintTypeInfo

type ConstraintTypeInfo = | ConstraintTypeInfoConstrained
  | ConstraintTypeInfoNonGeneric
  | ConstraintTypeInfoUnconstrained;

---