Section 2.5.4Source: server/src/parser/extractors/SymbolExtractor.ts

Variables & Destructuring Patterns

Extracting declared variables across plain identifiers, ObjectPattern destructuring with aliases, and ArrayPattern unpacking.

Source: server/src/parser/extractors/SymbolExtractor.ts

The Destructuring Engine: `getVariableName`

In JavaScript/TypeScript, a single VariableDeclarator statement can declare multiple variables via pattern matching. The extractor unpacks each into independent ParsedSymbol records:

server/src/parser/extractors/SymbolExtractor.ts

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private getVariableName(path: NodePath<VariableDeclarator>): string[] {
    const id = path.node.id;

    // 1. Plain Identifier: const count = 10
    if (id.type === "Identifier") {
        return [id.name];
    }

    // 2. ObjectPattern: const { name, age: userAge } = user
    if (id.type === "ObjectPattern") {
        return id.properties
            .filter(property => property.type === "ObjectProperty")
            .map(property => {
                // Incase of aliases ({ age: userAge }), symbol name is "userAge"
                if (property.value.type === "Identifier") {
                    return property.value.name;
                }
                return null;
            })
            .filter((name): name is string => name !== null);
    }

    // 3. ArrayPattern: const [first, second] = items
    if (id.type === "ArrayPattern") {
        return id.elements
            .filter(element => element?.type === "Identifier")
            .map(element => element?.name);
    }

    return [];
}

Variables Initialized with Object Literals

When a variable is initialized with an ObjectExpression (e.g. const serverConfig = { port: 8080 }), the variable symbol itself acts as a container. It is pushed to symbolStack so that nested ObjectProperty and ObjectMethod declarations can set the variable as their parentSymbolId.

2.5.3 Classes & Methods

2.5.5 TypeScript Type Declarations