estree.ts

import { type TokenType } from "../tokenizer/types";
import type Parser from "../parser";
import type { ExpressionErrors } from "../parser/util";
import type * as N from "../types";
import type { Node as NodeType, NodeBase, File } from "../types";
import type { Position } from "../util/location";
import { Errors } from "../parse-error";
import type { Undone } from "../parser/node";
import type { BindingTypes } from "../util/scopeflags";

const { defineProperty } = Object;
const toUnenumerable = (object: any, key: string) =>
  defineProperty(object, key, { enumerable: false, value: object[key] });

function toESTreeLocation(node: any) {
  node.loc.start && toUnenumerable(node.loc.start, "index");
  node.loc.end && toUnenumerable(node.loc.end, "index");

  return node;
}

export default (superClass: typeof Parser) =>
  class ESTreeParserMixin extends superClass implements Parser {
    parse(): File {
      const file = toESTreeLocation(super.parse());

      if (this.options.tokens) {
        file.tokens = file.tokens.map(toESTreeLocation);
      }

      return file;
    }

    // @ts-expect-error ESTree plugin changes node types
    parseRegExpLiteral({ pattern, flags }): N.EstreeRegExpLiteral {
      let regex: RegExp | null = null;
      try {
        regex = new RegExp(pattern, flags);
      } catch (e) {
        // In environments that don't support these flags value will
        // be null as the regex can't be represented natively.
      }
      const node = this.estreeParseLiteral<N.EstreeRegExpLiteral>(regex);
      node.regex = { pattern, flags };

      return node;
    }

    // @ts-expect-error ESTree plugin changes node types
    parseBigIntLiteral(value: any): N.Node {
      // https://github.com/estree/estree/blob/master/es2020.md#bigintliteral
      let bigInt: BigInt | null;
      try {
        bigInt = BigInt(value);
      } catch {
        bigInt = null;
      }
      const node = this.estreeParseLiteral<N.EstreeBigIntLiteral>(bigInt);
      node.bigint = String(node.value || value);

      return node;
    }

    // @ts-expect-error ESTree plugin changes node types
    parseDecimalLiteral(value: any): N.Node {
      // https://github.com/estree/estree/blob/master/experimental/decimal.md
      // todo: use BigDecimal when node supports it.
      const decimal: null = null;
      const node = this.estreeParseLiteral(decimal);
      node.decimal = String(node.value || value);

      return node;
    }

    estreeParseLiteral<T extends N.Node>(value: any) {
      // @ts-expect-error ESTree plugin changes node types
      return this.parseLiteral<T>(value, "Literal");
    }

    // @ts-expect-error ESTree plugin changes node types
    parseStringLiteral(value: any): N.Node {
      return this.estreeParseLiteral(value);
    }

    parseNumericLiteral(value: any): any {
      return this.estreeParseLiteral(value);
    }

    // @ts-expect-error ESTree plugin changes node types
    parseNullLiteral(): N.Node {
      return this.estreeParseLiteral(null);
    }

    parseBooleanLiteral(value: boolean): N.BooleanLiteral {
      return this.estreeParseLiteral(value);
    }

    // Cast a Directive to an ExpressionStatement. Mutates the input Directive.
    directiveToStmt(directive: N.Directive): N.ExpressionStatement {
      const expression = directive.value as any as N.EstreeLiteral;
      delete directive.value;

      expression.type = "Literal";
      // @ts-expect-error N.EstreeLiteral.raw is not defined.
      expression.raw = expression.extra.raw;
      expression.value = expression.extra.expressionValue;

      const stmt = directive as any as N.ExpressionStatement;
      stmt.type = "ExpressionStatement";
      stmt.expression = expression;
      // @ts-expect-error N.ExpressionStatement.directive is not defined
      stmt.directive = expression.extra.rawValue;

      delete expression.extra;

      return stmt;
    }

    // ==================================
    // Overrides
    // ==================================

    initFunction(node: N.BodilessFunctionOrMethodBase, isAsync: boolean): void {
      super.initFunction(node, isAsync);
      node.expression = false;
    }

    checkDeclaration(node: N.Pattern | N.ObjectProperty): void {
      if (node != null && this.isObjectProperty(node)) {
        // @ts-expect-error plugin typings
        this.checkDeclaration((node as unknown as N.EstreeProperty).value);
      } else {
        super.checkDeclaration(node);
      }
    }

    getObjectOrClassMethodParams(method: N.ObjectMethod | N.ClassMethod) {
      return (method as any as N.EstreeProperty | N.EstreeMethodDefinition)
        .value.params;
    }

    isValidDirective(stmt: N.Statement): boolean {
      return (
        stmt.type === "ExpressionStatement" &&
        stmt.expression.type === "Literal" &&
        typeof stmt.expression.value === "string" &&
        !stmt.expression.extra?.parenthesized
      );
    }

    parseBlockBody(
      node: N.BlockStatementLike,
      allowDirectives: boolean | undefined | null,
      topLevel: boolean,
      end: TokenType,
      afterBlockParse?: (hasStrictModeDirective: boolean) => void,
    ): void {
      super.parseBlockBody(
        node,
        allowDirectives,
        topLevel,
        end,
        afterBlockParse,
      );

      const directiveStatements = node.directives.map(d =>
        this.directiveToStmt(d),
      );
      // @ts-expect-error estree plugin typings
      node.body = directiveStatements.concat(node.body);
      delete node.directives;
    }

    pushClassMethod(
      classBody: N.ClassBody,
      method: N.ClassMethod,
      isGenerator: boolean,
      isAsync: boolean,
      isConstructor: boolean,
      allowsDirectSuper: boolean,
    ): void {
      this.parseMethod(
        method,
        isGenerator,
        isAsync,
        isConstructor,
        allowsDirectSuper,
        "ClassMethod",
        true,
      );
      if (method.typeParameters) {
        // @ts-expect-error mutate AST types
        method.value.typeParameters = method.typeParameters;
        delete method.typeParameters;
      }
      classBody.body.push(method);
    }

    parsePrivateName(): any {
      const node = super.parsePrivateName();
      if (!process.env.BABEL_8_BREAKING) {
        if (!this.getPluginOption("estree", "classFeatures")) {
          return node;
        }
      }
      return this.convertPrivateNameToPrivateIdentifier(node);
    }

    convertPrivateNameToPrivateIdentifier(
      node: N.PrivateName,
    ): N.EstreePrivateIdentifier {
      const name = super.getPrivateNameSV(node);
      node = node as any;
      delete node.id;
      // @ts-expect-error mutate AST types
      node.name = name;
      // @ts-expect-error mutate AST types
      node.type = "PrivateIdentifier";
      return node as unknown as N.EstreePrivateIdentifier;
    }

    isPrivateName(node: N.Node): boolean {
      if (!process.env.BABEL_8_BREAKING) {
        if (!this.getPluginOption("estree", "classFeatures")) {
          return super.isPrivateName(node);
        }
      }
      return node.type === "PrivateIdentifier";
    }

    getPrivateNameSV(node: N.Node): string {
      if (!process.env.BABEL_8_BREAKING) {
        if (!this.getPluginOption("estree", "classFeatures")) {
          return super.getPrivateNameSV(node);
        }
      }
      return node.name;
    }

    // @ts-expect-error plugin may override interfaces
    parseLiteral<T extends N.Literal>(value: any, type: T["type"]): T {
      const node = super.parseLiteral<T>(value, type);
      // @ts-expect-error mutating AST types
      node.raw = node.extra.raw;
      delete node.extra;

      return node;
    }

    parseFunctionBody(
      node: N.Function,
      allowExpression?: boolean | null,
      isMethod: boolean = false,
    ): void {
      super.parseFunctionBody(node, allowExpression, isMethod);
      node.expression = node.body.type !== "BlockStatement";
    }

    // @ts-expect-error plugin may override interfaces
    parseMethod<
      T extends N.ClassPrivateMethod | N.ObjectMethod | N.ClassMethod,
    >(
      node: Undone<T>,
      isGenerator: boolean,
      isAsync: boolean,
      isConstructor: boolean,
      allowDirectSuper: boolean,
      type: T["type"],
      inClassScope: boolean = false,
    ): N.EstreeMethodDefinition {
      let funcNode = this.startNode<N.MethodLike>();
      funcNode.kind = node.kind; // provide kind, so super method correctly sets state
      funcNode = super.parseMethod(
        // @ts-expect-error todo(flow->ts)
        funcNode,
        isGenerator,
        isAsync,
        isConstructor,
        allowDirectSuper,
        type,
        inClassScope,
      );
      // @ts-expect-error mutate AST types
      funcNode.type = "FunctionExpression";
      delete funcNode.kind;
      // @ts-expect-error mutate AST types
      node.value = funcNode;
      if (type === "ClassPrivateMethod") {
        node.computed = false;
      }
      return this.finishNode(
        // @ts-expect-error cast methods to estree types
        node as Undone<N.EstreeMethodDefinition>,
        "MethodDefinition",
      );
    }

    parseClassProperty(...args: [N.ClassProperty]): any {
      const propertyNode = super.parseClassProperty(...args) as any;
      if (!process.env.BABEL_8_BREAKING) {
        if (!this.getPluginOption("estree", "classFeatures")) {
          return propertyNode as N.EstreePropertyDefinition;
        }
      }
      propertyNode.type = "PropertyDefinition";
      return propertyNode as N.EstreePropertyDefinition;
    }

    parseClassPrivateProperty(...args: [N.ClassPrivateProperty]): any {
      const propertyNode = super.parseClassPrivateProperty(...args) as any;
      if (!process.env.BABEL_8_BREAKING) {
        if (!this.getPluginOption("estree", "classFeatures")) {
          return propertyNode as N.EstreePropertyDefinition;
        }
      }
      propertyNode.type = "PropertyDefinition";
      propertyNode.computed = false;
      return propertyNode as N.EstreePropertyDefinition;
    }

    parseObjectMethod(
      prop: N.ObjectMethod,
      isGenerator: boolean,
      isAsync: boolean,
      isPattern: boolean,
      isAccessor: boolean,
    ): N.ObjectMethod | undefined | null {
      const node: N.EstreeProperty = super.parseObjectMethod(
        prop,
        isGenerator,
        isAsync,
        isPattern,
        isAccessor,
      ) as any;

      if (node) {
        node.type = "Property";
        if ((node as any as N.ClassMethod).kind === "method") {
          node.kind = "init";
        }
        node.shorthand = false;
      }

      return node as any;
    }

    parseObjectProperty(
      prop: N.ObjectProperty,
      startLoc: Position | undefined | null,
      isPattern: boolean,
      refExpressionErrors?: ExpressionErrors | null,
    ): N.ObjectProperty | undefined | null {
      const node: N.EstreeProperty = super.parseObjectProperty(
        prop,
        startLoc,
        isPattern,
        refExpressionErrors,
      ) as any;

      if (node) {
        node.kind = "init";
        node.type = "Property";
      }

      return node as any;
    }

    isValidLVal(
      type: string,
      isUnparenthesizedInAssign: boolean,
      binding: BindingTypes,
    ) {
      return type === "Property"
        ? "value"
        : super.isValidLVal(type, isUnparenthesizedInAssign, binding);
    }

    isAssignable(node: N.Node, isBinding?: boolean): boolean {
      if (node != null && this.isObjectProperty(node)) {
        return this.isAssignable(node.value, isBinding);
      }
      return super.isAssignable(node, isBinding);
    }

    toAssignable(node: N.Node, isLHS: boolean = false): void {
      if (node != null && this.isObjectProperty(node)) {
        const { key, value } = node;
        if (this.isPrivateName(key)) {
          this.classScope.usePrivateName(
            this.getPrivateNameSV(key),
            key.loc.start,
          );
        }
        this.toAssignable(value, isLHS);
      } else {
        super.toAssignable(node, isLHS);
      }
    }

    toAssignableObjectExpressionProp(
      prop: N.Node,
      isLast: boolean,
      isLHS: boolean,
    ) {
      if (prop.kind === "get" || prop.kind === "set") {
        this.raise(Errors.PatternHasAccessor, { at: prop.key });
      } else if (prop.method) {
        this.raise(Errors.PatternHasMethod, { at: prop.key });
      } else {
        super.toAssignableObjectExpressionProp(prop, isLast, isLHS);
      }
    }

    finishCallExpression<T extends N.CallExpression | N.OptionalCallExpression>(
      unfinished: Undone<T>,
      optional: boolean,
    ): T {
      const node = super.finishCallExpression(unfinished, optional);

      if (node.callee.type === "Import") {
        (node as N.Node as N.EstreeImportExpression).type = "ImportExpression";
        (node as N.Node as N.EstreeImportExpression).source = node.arguments[0];
        if (
          this.hasPlugin("importAttributes") ||
          this.hasPlugin("importAssertions")
        ) {
          (node as N.Node as N.EstreeImportExpression).attributes =
            node.arguments[1] ?? null;
        }
        // arguments isn't optional in the type definition
        delete node.arguments;
        // callee isn't optional in the type definition
        delete node.callee;
      }

      return node;
    }

    toReferencedArguments(
      node:
        | N.CallExpression
        | N.OptionalCallExpression
        | N.EstreeImportExpression,
      /* isParenthesizedExpr?: boolean, */
    ) {
      // ImportExpressions do not have an arguments array.
      if (node.type === "ImportExpression") {
        return;
      }

      super.toReferencedArguments(node);
    }

    parseExport(
      unfinished: Undone<N.AnyExport>,
      decorators: N.Decorator[] | null,
    ) {
      const exportStartLoc = this.state.lastTokStartLoc;
      const node = super.parseExport(unfinished, decorators);

      switch (node.type) {
        case "ExportAllDeclaration":
          // @ts-expect-error mutating AST types
          node.exported = null;
          break;

        case "ExportNamedDeclaration":
          if (
            node.specifiers.length === 1 &&
            // @ts-expect-error mutating AST types
            node.specifiers[0].type === "ExportNamespaceSpecifier"
          ) {
            // @ts-expect-error mutating AST types
            node.type = "ExportAllDeclaration";
            // @ts-expect-error mutating AST types
            node.exported = node.specifiers[0].exported;
            delete node.specifiers;
          }

        // fallthrough
        case "ExportDefaultDeclaration":
          {
            const { declaration } = node;
            if (
              declaration?.type === "ClassDeclaration" &&
              declaration.decorators?.length > 0 &&
              // decorator comes before export
              declaration.start === node.start
            ) {
              this.resetStartLocation(
                node,
                // For compatibility with ESLint's keyword-spacing rule, which assumes that an
                // export declaration must start with export.
                // https://github.com/babel/babel/issues/15085
                // Here we reset export declaration's start to be the start of the export token
                exportStartLoc,
              );
            }
          }

          break;
      }

      return node;
    }

    parseSubscript(
      base: N.Expression,
      startLoc: Position,
      noCalls: boolean | undefined | null,
      state: N.ParseSubscriptState,
    ) {
      const node = super.parseSubscript(base, startLoc, noCalls, state);

      if (state.optionalChainMember) {
        // https://github.com/estree/estree/blob/master/es2020.md#chainexpression
        if (
          node.type === "OptionalMemberExpression" ||
          node.type === "OptionalCallExpression"
        ) {
          node.type = node.type.substring(8); // strip Optional prefix
        }
        if (state.stop) {
          const chain = this.startNodeAtNode(node);
          chain.expression = node;
          return this.finishNode(chain, "ChainExpression");
        }
      } else if (
        node.type === "MemberExpression" ||
        node.type === "CallExpression"
      ) {
        node.optional = false;
      }

      return node;
    }

    hasPropertyAsPrivateName(node: N.Node): boolean {
      if (node.type === "ChainExpression") {
        node = node.expression;
      }
      return super.hasPropertyAsPrivateName(node);
    }

    // @ts-expect-error override interfaces
    isObjectProperty(node: N.Node): boolean {
      return node.type === "Property" && node.kind === "init" && !node.method;
    }

    isObjectMethod(node: N.Node): boolean {
      return node.method || node.kind === "get" || node.kind === "set";
    }

    finishNodeAt<T extends NodeType>(
      node: Undone<T>,
      type: T["type"],
      endLoc: Position,
    ): T {
      return toESTreeLocation(super.finishNodeAt(node, type, endLoc));
    }

    resetStartLocation(node: N.Node, startLoc: Position) {
      super.resetStartLocation(node, startLoc);
      toESTreeLocation(node);
    }

    resetEndLocation(
      node: NodeBase,
      endLoc: Position = this.state.lastTokEndLoc,
    ): void {
      super.resetEndLocation(node, endLoc);
      toESTreeLocation(node);
    }
  };