Struct SyntheticNameBuilder 

pub struct SyntheticNameBuilder;

Generates stable synthetic names for anonymous functions and classes.

Anonymous functions and classes without explicit names need identifiers for call graph tracking. This builder creates deterministic names based on the node type and source location.

Naming Strategy

• Line-based (legacy): <anon:function@{line}>
• Hash-based (FR-JS-PATCH-2): anon:arrow:a3f2b1c0

Hash-based names are computed from node content + location for stability across refactors while avoiding line-number brittleness.

Implementations

impl SyntheticNameBuilder

pub fn from_node(node: &Node<'_>, _content: &[u8], context: &str) -> String

Generate a line-based synthetic name from an AST node (legacy).

Arguments

• node - The AST node (function or class)
• content - Source file bytes (for context extraction if needed)
• context - Context type (“function”, “class”, “arrow”, etc.)

Returns

A stable synthetic name like <anon:function@42>

Example

// For anonymous function at line 15:
let name = SyntheticNameBuilder::from_node(&node, content, "function");
// Returns: "<anon:function@15>"

pub fn from_node_with_hash( node: &Node<'_>, content: &[u8], context_label: &str, ) -> String

Generate a hash-based synthetic name from an AST node (FR-JS-PATCH-2).

Computes a stable hash from node text content and start position. This provides deterministic IDs that survive line number changes during refactoring, while remaining unique within a file.

Arguments

• node - The AST node (function or class)
• content - Source file bytes (used to hash node text)
• context_label - Context type (“arrow”, “class”, “function”, etc.)

Returns

A hash-based synthetic name like anon:arrow:a3f2b1c0

Example

// For anonymous arrow function:
let name = SyntheticNameBuilder::from_node_with_hash(&node, content, "arrow");
// Returns: "anon:arrow:4a7b9c2d"