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📄 parameter-properties.ts

📊 Analysis Summary

Metric	Count
🔧 Functions	3
📦 Imports	4
📊 Variables & Constants	5
📐 Interfaces	1
📑 Type Aliases	4

📚 Table of Contents

• Imports
• Variables & Constants
• Functions
• Interfaces
• Type Aliases

🛠️ File Location:

📂 packages/eslint-plugin/src/rules/parameter-properties.ts

📦 Imports

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

---

Variables & Constants

Name	Type	Kind	Value	Exported
modifiers	Modifier[]	const	[]	✗
name	any	const	`node.parameter.type === AST_NODE_TYPES.Identifier
? node.parameter.name
: // has to be an Identifier or TSC will throw an error
(node.parameter.left as TSESTree.Identifier).name`	✗
propertyNodesByNameStack	Map<string, PropertyNodes>[]	const	[]	✗
propertyNodesByName	Map<string, PropertyNodes>	const	propertyNodesByNameStack[propertyNodesByNameStack.length - 1]	✗
created	PropertyNodes	const	{}	✗

---

Functions

getModifiers(node: TSESTree.PropertyDefinition | TSESTree.TSParameterProperty): Modifier

Code

function getModifiers(
      node: TSESTree.PropertyDefinition | TSESTree.TSParameterProperty,
    ): Modifier {
      const modifiers: Modifier[] = [];

      if (node.accessibility) {
        modifiers.push(node.accessibility);
      }
      if (node.readonly) {
        modifiers.push('readonly');
      }

      return modifiers.filter(Boolean).join(' ') as Modifier;
    }

• JSDoc:

  /**
       * Gets the modifiers of `node`.
       * @param node the node to be inspected.
       */
  

• Parameters:

• node: TSESTree.PropertyDefinition | TSESTree.TSParameterProperty
• Return Type: Modifier
• Calls:
• modifiers.push
• modifiers.filter(Boolean).join

getNodesByName(name: string): PropertyNodes

Code

function getNodesByName(name: string): PropertyNodes {
      const propertyNodesByName =
        propertyNodesByNameStack[propertyNodesByNameStack.length - 1];
      const existing = propertyNodesByName.get(name);
      if (existing) {
        return existing;
      }

      const created: PropertyNodes = {};
      propertyNodesByName.set(name, created);
      return created;
    }

• Parameters:
• name: string
• Return Type: PropertyNodes
• Calls:
• propertyNodesByName.get
• propertyNodesByName.set

typeAnnotationsMatch(classProperty: TSESTree.PropertyDefinition, constructorParameter: TSESTree.Identifier): boolean

Code

function typeAnnotationsMatch(
      classProperty: TSESTree.PropertyDefinition,
      constructorParameter: TSESTree.Identifier,
    ): boolean {
      if (
        !classProperty.typeAnnotation ||
        !constructorParameter.typeAnnotation
      ) {
        return (
          classProperty.typeAnnotation === constructorParameter.typeAnnotation
        );
      }

      return (
        context.sourceCode.getText(classProperty.typeAnnotation) ===
        context.sourceCode.getText(constructorParameter.typeAnnotation)
      );
    }

• Parameters:
• classProperty: TSESTree.PropertyDefinition
• constructorParameter: TSESTree.Identifier
• Return Type: boolean
• Calls:
• context.sourceCode.getText

---

Interfaces

PropertyNodes

Interface Code

interface PropertyNodes {
      classProperty?: TSESTree.PropertyDefinition;
      constructorAssignment?: TSESTree.AssignmentExpression;
      constructorParameter?: TSESTree.Identifier;
    }

Properties

Name	Type	Optional	Description
classProperty	TSESTree.PropertyDefinition	✓
constructorAssignment	TSESTree.AssignmentExpression	✓
constructorParameter	TSESTree.Identifier	✓

---

Type Aliases

Modifier

type Modifier = | 'private'
  | 'private readonly'
  | 'protected'
  | 'protected readonly'
  | 'public'
  | 'public readonly'
  | 'readonly';

Prefer

type Prefer = 'class-property' | 'parameter-property';

Options

type Options = [
  {
    allow?: Modifier[];
    prefer?: Prefer;
  },
];

MessageIds

type MessageIds = 'preferClassProperty' | 'preferParameterProperty';

---