Rename "babylon" to "@babel/parser" (#7937) 🎉

packages/babel-parser/src/plugins/estree.js

@@ -0,0 +1,363 @@
+// @flow
+
+import { types as tt, TokenType } from "../tokenizer/types";
+import type Parser from "../parser";
+import * as N from "../types";
+import type { Pos, Position } from "../util/location";
+
+function isSimpleProperty(node: N.Node): boolean {
+  return (
+    node != null &&
+    node.type === "Property" &&
+    node.kind === "init" &&
+    node.method === false
+  );
+}
+
+export default (superClass: Class<Parser>): Class<Parser> =>
+  class extends superClass {
+    estreeParseRegExpLiteral({ pattern, flags }: N.RegExpLiteral): N.Node {
+      let regex = 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(regex);
+      node.regex = { pattern, flags };
+
+      return node;
+    }
+
+    estreeParseLiteral(value: any): N.Node {
+      return this.parseLiteral(value, "Literal");
+    }
+
+    directiveToStmt(directive: N.Directive): N.ExpressionStatement {
+      const directiveLiteral = directive.value;
+
+      const stmt = this.startNodeAt(directive.start, directive.loc.start);
+      const expression = this.startNodeAt(
+        directiveLiteral.start,
+        directiveLiteral.loc.start,
+      );
+
+      expression.value = directiveLiteral.value;
+      expression.raw = directiveLiteral.extra.raw;
+
+      stmt.expression = this.finishNodeAt(
+        expression,
+        "Literal",
+        directiveLiteral.end,
+        directiveLiteral.loc.end,
+      );
+      stmt.directive = directiveLiteral.extra.raw.slice(1, -1);
+
+      return this.finishNodeAt(
+        stmt,
+        "ExpressionStatement",
+        directive.end,
+        directive.loc.end,
+      );
+    }
+
+    // ==================================
+    // Overrides
+    // ==================================
+
+    initFunction(
+      node: N.BodilessFunctionOrMethodBase,
+      isAsync: ?boolean,
+    ): void {
+      super.initFunction(node, isAsync);
+      node.expression = false;
+    }
+
+    checkDeclaration(node: N.Pattern | N.ObjectProperty): void {
+      if (isSimpleProperty(node)) {
+        this.checkDeclaration(((node: any): N.EstreeProperty).value);
+      } else {
+        super.checkDeclaration(node);
+      }
+    }
+
+    checkGetterSetterParams(method: N.ObjectMethod | N.ClassMethod): void {
+      const prop = ((method: any): N.EstreeProperty | N.EstreeMethodDefinition);
+      const paramCount = prop.kind === "get" ? 0 : 1;
+      const start = prop.start;
+      if (prop.value.params.length !== paramCount) {
+        if (prop.kind === "get") {
+          this.raise(start, "getter must not have any formal parameters");
+        } else {
+          this.raise(start, "setter must have exactly one formal parameter");
+        }
+      }
+
+      if (prop.kind === "set" && prop.value.params[0].type === "RestElement") {
+        this.raise(
+          start,
+          "setter function argument must not be a rest parameter",
+        );
+      }
+    }
+
+    checkLVal(
+      expr: N.Expression,
+      isBinding: ?boolean,
+      checkClashes: ?{ [key: string]: boolean },
+      contextDescription: string,
+    ): void {
+      switch (expr.type) {
+        case "ObjectPattern":
+          expr.properties.forEach(prop => {
+            this.checkLVal(
+              prop.type === "Property" ? prop.value : prop,
+              isBinding,
+              checkClashes,
+              "object destructuring pattern",
+            );
+          });
+          break;
+        default:
+          super.checkLVal(expr, isBinding, checkClashes, contextDescription);
+      }
+    }
+
+    checkPropClash(
+      prop: N.ObjectMember,
+      propHash: { [key: string]: boolean },
+    ): void {
+      if (prop.computed || !isSimpleProperty(prop)) return;
+
+      const key = prop.key;
+      // It is either an Identifier or a String/NumericLiteral
+      const name = key.type === "Identifier" ? key.name : String(key.value);
+
+      if (name === "__proto__") {
+        if (propHash.proto) {
+          this.raise(key.start, "Redefinition of __proto__ property");
+        }
+        propHash.proto = true;
+      }
+    }
+
+    isStrictBody(node: { body: N.BlockStatement }): boolean {
+      const isBlockStatement = node.body.type === "BlockStatement";
+
+      if (isBlockStatement && node.body.body.length > 0) {
+        for (const directive of node.body.body) {
+          if (
+            directive.type === "ExpressionStatement" &&
+            directive.expression.type === "Literal"
+          ) {
+            if (directive.expression.value === "use strict") return true;
+          } else {
+            // Break for the first non literal expression
+            break;
+          }
+        }
+      }
+
+      return false;
+    }
+
+    isValidDirective(stmt: N.Statement): boolean {
+      return (
+        stmt.type === "ExpressionStatement" &&
+        stmt.expression.type === "Literal" &&
+        typeof stmt.expression.value === "string" &&
+        (!stmt.expression.extra || !stmt.expression.extra.parenthesized)
+      );
+    }
+
+    stmtToDirective(stmt: N.Statement): N.Directive {
+      const directive = super.stmtToDirective(stmt);
+      const value = stmt.expression.value;
+
+      // Reset value to the actual value as in estree mode we want
+      // the stmt to have the real value and not the raw value
+      directive.value.value = value;
+
+      return directive;
+    }
+
+    parseBlockBody(
+      node: N.BlockStatementLike,
+      allowDirectives: ?boolean,
+      topLevel: boolean,
+      end: TokenType,
+    ): void {
+      super.parseBlockBody(node, allowDirectives, topLevel, end);
+
+      const directiveStatements = node.directives.map(d =>
+        this.directiveToStmt(d),
+      );
+      node.body = directiveStatements.concat(node.body);
+      delete node.directives;
+    }
+
+    pushClassMethod(
+      classBody: N.ClassBody,
+      method: N.ClassMethod,
+      isGenerator: boolean,
+      isAsync: boolean,
+      isConstructor: boolean,
+    ): void {
+      this.parseMethod(
+        method,
+        isGenerator,
+        isAsync,
+        isConstructor,
+        "MethodDefinition",
+      );
+      if (method.typeParameters) {
+        // $FlowIgnore
+        method.value.typeParameters = method.typeParameters;
+        delete method.typeParameters;
+      }
+      classBody.body.push(method);
+    }
+
+    parseExprAtom(refShorthandDefaultPos?: ?Pos): N.Expression {
+      switch (this.state.type) {
+        case tt.regexp:
+          return this.estreeParseRegExpLiteral(this.state.value);
+
+        case tt.num:
+        case tt.string:
+          return this.estreeParseLiteral(this.state.value);
+
+        case tt._null:
+          return this.estreeParseLiteral(null);
+
+        case tt._true:
+          return this.estreeParseLiteral(true);
+
+        case tt._false:
+          return this.estreeParseLiteral(false);
+
+        default:
+          return super.parseExprAtom(refShorthandDefaultPos);
+      }
+    }
+
+    parseLiteral<T: N.Literal>(
+      value: any,
+      type: /*T["kind"]*/ string,
+      startPos?: number,
+      startLoc?: Position,
+    ): T {
+      const node = super.parseLiteral(value, type, startPos, startLoc);
+      node.raw = node.extra.raw;
+      delete node.extra;
+
+      return node;
+    }
+
+    parseFunctionBody(node: N.Function, allowExpression: ?boolean): void {
+      super.parseFunctionBody(node, allowExpression);
+      node.expression = node.body.type !== "BlockStatement";
+    }
+
+    parseMethod<T: N.MethodLike>(
+      node: T,
+      isGenerator: boolean,
+      isAsync: boolean,
+      isConstructor: boolean,
+      type: string,
+    ): T {
+      let funcNode = this.startNode();
+      funcNode.kind = node.kind; // provide kind, so super method correctly sets state
+      funcNode = super.parseMethod(
+        funcNode,
+        isGenerator,
+        isAsync,
+        isConstructor,
+        "FunctionExpression",
+      );
+      delete funcNode.kind;
+      // $FlowIgnore
+      node.value = funcNode;
+
+      return this.finishNode(node, type);
+    }
+
+    parseObjectMethod(
+      prop: N.ObjectMethod,
+      isGenerator: boolean,
+      isAsync: boolean,
+      isPattern: boolean,
+      containsEsc: boolean,
+    ): ?N.ObjectMethod {
+      const node: N.EstreeProperty = (super.parseObjectMethod(
+        prop,
+        isGenerator,
+        isAsync,
+        isPattern,
+        containsEsc,
+      ): any);
+
+      if (node) {
+        node.type = "Property";
+        if (node.kind === "method") node.kind = "init";
+        node.shorthand = false;
+      }
+
+      return (node: any);
+    }
+
+    parseObjectProperty(
+      prop: N.ObjectProperty,
+      startPos: ?number,
+      startLoc: ?Position,
+      isPattern: boolean,
+      refShorthandDefaultPos: ?Pos,
+    ): ?N.ObjectProperty {
+      const node: N.EstreeProperty = (super.parseObjectProperty(
+        prop,
+        startPos,
+        startLoc,
+        isPattern,
+        refShorthandDefaultPos,
+      ): any);
+
+      if (node) {
+        node.kind = "init";
+        node.type = "Property";
+      }
+
+      return (node: any);
+    }
+
+    toAssignable(
+      node: N.Node,
+      isBinding: ?boolean,
+      contextDescription: string,
+    ): N.Node {
+      if (isSimpleProperty(node)) {
+        this.toAssignable(node.value, isBinding, contextDescription);
+
+        return node;
+      }
+
+      return super.toAssignable(node, isBinding, contextDescription);
+    }
+
+    toAssignableObjectExpressionProp(
+      prop: N.Node,
+      isBinding: ?boolean,
+      isLast: boolean,
+    ) {
+      if (prop.kind === "get" || prop.kind === "set") {
+        this.raise(
+          prop.key.start,
+          "Object pattern can't contain getter or setter",
+        );
+      } else if (prop.method) {
+        this.raise(prop.key.start, "Object pattern can't contain methods");
+      } else {
+        super.toAssignableObjectExpressionProp(prop, isBinding, isLast);
+      }
+    }
+  };