Skip to content

⬅️ Back to Table of Contents

📄 no-unnecessary-parameter-property-assignment.ts

📊 Analysis Summary

Metric Count
🔧 Functions 9
📦 Imports 7
📊 Variables & Constants 2

📚 Table of Contents

🛠️ File Location:

📂 packages/eslint-plugin/src/rules/no-unnecessary-parameter-property-assignment.ts

📦 Imports

Name Source
TSESTree @typescript-eslint/utils
DefinitionType @typescript-eslint/scope-manager
AST_NODE_TYPES @typescript-eslint/utils
ASTUtils @typescript-eslint/utils
createRule ../util
getStaticStringValue ../util
nullThrows ../util

Variables & Constants

Name Type Kind Value Exported
UNNECESSARY_OPERATORS Set<string> const new Set(['??=', '&&=', '=', '||=']) ✗
reportInfoStack `{
assignedBeforeConstructor: Set;
assignedBeforeUnnecessary: Set;
unnecessaryAssignments: {
name: string;
node: TSESTree.AssignmentExpression;
}[];
}[]| const |[]` ✗

Functions

isThisMemberExpression(node: TSESTree.Node): node is TSESTree.MemberExpression

Code 
function isThisMemberExpression(
      node: TSESTree.Node,
    ): node is TSESTree.MemberExpression {
      return (
        node.type === AST_NODE_TYPES.MemberExpression &&
        node.object.type === AST_NODE_TYPES.ThisExpression
      );
    }
  • Parameters:
  • node: TSESTree.Node
  • Return Type: node is TSESTree.MemberExpression

getPropertyName(node: TSESTree.Node): string | null

Code 
function getPropertyName(node: TSESTree.Node): string | null {
      if (!isThisMemberExpression(node)) {
        return null;
      }

      if (node.property.type === AST_NODE_TYPES.Identifier) {
        return node.property.name;
      }
      if (node.computed) {
        return getStaticStringValue(node.property);
      }
      return null;
    }
  • Parameters:
  • node: TSESTree.Node
  • Return Type: string | null
  • Calls:
  • isThisMemberExpression
  • getStaticStringValue (from ../util)

`findParentFunction(node: TSESTree.Node | undefined): | TSESTree.ArrowFunctionExpression

  | TSESTree.FunctionDeclaration
  | TSESTree.FunctionExpression
  | undefined`
Code 
function findParentFunction(
      node: TSESTree.Node | undefined,
    ):
      | TSESTree.ArrowFunctionExpression
      | TSESTree.FunctionDeclaration
      | TSESTree.FunctionExpression
      | undefined {
      if (
        !node ||
        node.type === AST_NODE_TYPES.FunctionDeclaration ||
        node.type === AST_NODE_TYPES.FunctionExpression ||
        node.type === AST_NODE_TYPES.ArrowFunctionExpression
      ) {
        return node;
      }
      return findParentFunction(node.parent);
    }
  • Parameters:
  • node: TSESTree.Node | undefined
  • Return Type: | TSESTree.ArrowFunctionExpression | TSESTree.FunctionDeclaration | TSESTree.FunctionExpression | undefined
  • Calls:
  • findParentFunction

findParentPropertyDefinition(node: TSESTree.Node | undefined): TSESTree.PropertyDefinition | undefined

Code 
function findParentPropertyDefinition(
      node: TSESTree.Node | undefined,
    ): TSESTree.PropertyDefinition | undefined {
      if (!node || node.type === AST_NODE_TYPES.PropertyDefinition) {
        return node;
      }
      return findParentPropertyDefinition(node.parent);
    }
  • Parameters:
  • node: TSESTree.Node | undefined
  • Return Type: TSESTree.PropertyDefinition | undefined
  • Calls:
  • findParentPropertyDefinition

isConstructorFunctionExpression(node: TSESTree.Node | undefined): node is TSESTree.FunctionExpression

Code 
function isConstructorFunctionExpression(
      node: TSESTree.Node | undefined,
    ): node is TSESTree.FunctionExpression {
      return (
        node?.type === AST_NODE_TYPES.FunctionExpression &&
        ASTUtils.isConstructor(node.parent)
      );
    }
  • Parameters:
  • node: TSESTree.Node | undefined
  • Return Type: node is TSESTree.FunctionExpression
  • Calls:
  • ASTUtils.isConstructor

isReferenceFromParameter(node: TSESTree.Identifier): boolean

Code 
function isReferenceFromParameter(node: TSESTree.Identifier): boolean {
      const scope = context.sourceCode.getScope(node);

      const rightRef = scope.references.find(
        ref => ref.identifier.name === node.name,
      );
      return rightRef?.resolved?.defs.at(0)?.type === DefinitionType.Parameter;
    }
  • Parameters:
  • node: TSESTree.Identifier
  • Return Type: boolean
  • Calls:
  • context.sourceCode.getScope
  • scope.references.find
  • rightRef?.resolved?.defs.at

isParameterPropertyWithName(node: TSESTree.Parameter, name: string): boolean

Code 
function isParameterPropertyWithName(
      node: TSESTree.Parameter,
      name: string,
    ): boolean {
      return (
        node.type === AST_NODE_TYPES.TSParameterProperty &&
        ((node.parameter.type === AST_NODE_TYPES.Identifier && // constructor (public foo) {}
          node.parameter.name === name) ||
          (node.parameter.type === AST_NODE_TYPES.AssignmentPattern && // constructor (public foo = 1) {}
            node.parameter.left.type === AST_NODE_TYPES.Identifier &&
            node.parameter.left.name === name))
      );
    }
  • Parameters:
  • node: TSESTree.Parameter
  • name: string
  • Return Type: boolean

getIdentifier(node: TSESTree.Node): TSESTree.Identifier | null

Code 
function getIdentifier(node: TSESTree.Node): TSESTree.Identifier | null {
      if (node.type === AST_NODE_TYPES.Identifier) {
        return node;
      }
      if (
        node.type === AST_NODE_TYPES.TSAsExpression ||
        node.type === AST_NODE_TYPES.TSNonNullExpression
      ) {
        return getIdentifier(node.expression);
      }
      return null;
    }
  • Parameters:
  • node: TSESTree.Node
  • Return Type: TSESTree.Identifier | null
  • Calls:
  • getIdentifier

isArrowIIFE(node: TSESTree.Node): boolean

Code 
function isArrowIIFE(node: TSESTree.Node): boolean {
      return (
        node.type === AST_NODE_TYPES.ArrowFunctionExpression &&
        node.parent.type === AST_NODE_TYPES.CallExpression
      );
    }
  • Parameters:
  • node: TSESTree.Node
  • Return Type: boolean