// @flow import type Parser from "./index"; import UtilParser from "./util"; import { SourceLocation, type Position } from "../util/location"; import type { Comment, Node as NodeType, NodeBase } from "../types"; // Start an AST node, attaching a start offset. class Node implements NodeBase { constructor(parser: Parser, pos: number, loc: Position) { this.start = pos; this.end = 0; this.loc = new SourceLocation(loc); if (parser?.options.ranges) this.range = [pos, 0]; if (parser?.filename) this.loc.filename = parser.filename; } type: string = ""; declare start: number; declare end: number; declare loc: SourceLocation; declare range: [number, number]; declare leadingComments: Array; declare trailingComments: Array; declare innerComments: Array; declare extra: { [key: string]: any }; } const NodePrototype = Node.prototype; if (!process.env.BABEL_8_BREAKING) { // $FlowIgnore NodePrototype.__clone = function (): Node { // $FlowIgnore const newNode: any = new Node(); const keys = Object.keys(this); for (let i = 0, length = keys.length; i < length; i++) { const key = keys[i]; // Do not clone comments that are already attached to the node if ( key !== "leadingComments" && key !== "trailingComments" && key !== "innerComments" ) { newNode[key] = this[key]; } } return newNode; }; } function clonePlaceholder(node: any): any { return cloneIdentifier(node); } export function cloneIdentifier(node: any): any { // We don't need to clone `typeAnnotations` and `optional`: because // cloneIdentifier is only used in object shorthand and named import/export. // Neither of them allow type annotations after the identifier or optional identifier const { type, start, end, loc, range, extra, name } = node; const cloned = Object.create(NodePrototype); cloned.type = type; cloned.start = start; cloned.end = end; cloned.loc = loc; cloned.range = range; cloned.extra = extra; cloned.name = name; if (type === "Placeholder") { cloned.expectedNode = node.expectedNode; } return cloned; } export function cloneStringLiteral(node: any): any { const { type, start, end, loc, range, extra } = node; if (type === "Placeholder") { return clonePlaceholder(node); } const cloned = Object.create(NodePrototype); cloned.type = "StringLiteral"; cloned.start = start; cloned.end = end; cloned.loc = loc; cloned.range = range; cloned.extra = extra; cloned.value = node.value; return cloned; } export class NodeUtils extends UtilParser { startNode(): T { // $FlowIgnore return new Node(this, this.state.start, this.state.startLoc); } startNodeAt(pos: number, loc: Position): T { // $FlowIgnore return new Node(this, pos, loc); } /** Start a new node with a previous node's location. */ startNodeAtNode(type: NodeType): T { return this.startNodeAt(type.start, type.loc.start); } // Finish an AST node, adding `type` and `end` properties. finishNode(node: T, type: string): T { return this.finishNodeAt( node, type, this.state.lastTokEnd, this.state.lastTokEndLoc, ); } // Finish node at given position finishNodeAt( node: T, type: string, pos: number, loc: Position, ): T { if (process.env.NODE_ENV !== "production" && node.end > 0) { throw new Error( "Do not call finishNode*() twice on the same node." + " Instead use resetEndLocation() or change type directly.", ); } node.type = type; node.end = pos; node.loc.end = loc; if (this.options.ranges) node.range[1] = pos; if (this.options.attachComment) this.processComment(node); return node; } resetStartLocation(node: NodeBase, start: number, startLoc: Position): void { node.start = start; node.loc.start = startLoc; if (this.options.ranges) node.range[0] = start; } resetEndLocation( node: NodeBase, end?: number = this.state.lastTokEnd, endLoc?: Position = this.state.lastTokEndLoc, ): void { node.end = end; node.loc.end = endLoc; if (this.options.ranges) node.range[1] = end; } /** * Reset the start location of node to the start location of locationNode */ resetStartLocationFromNode(node: NodeBase, locationNode: NodeBase): void { this.resetStartLocation(node, locationNode.start, locationNode.loc.start); } }