package.lib.index.js Maven / Gradle / Ivy

Go to download
Show more of this group Show more artifacts with this name
Show all versions of helper-simple-access Show documentation
Babel helper for ensuring that access to a given value is performed through simple accesses
The newest version!
"use strict";

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.default = simplifyAccess;
var _t = require("@babel/types");
const {
  LOGICAL_OPERATORS,
  assignmentExpression,
  binaryExpression,
  cloneNode,
  identifier,
  logicalExpression,
  numericLiteral,
  sequenceExpression,
  unaryExpression
} = _t;
const simpleAssignmentVisitor = {
  AssignmentExpression: {
    exit(path) {
      const {
        scope,
        seen,
        bindingNames
      } = this;
      if (path.node.operator === "=") return;
      if (seen.has(path.node)) return;
      seen.add(path.node);
      const left = path.get("left");
      if (!left.isIdentifier()) return;
      const localName = left.node.name;
      if (!bindingNames.has(localName)) return;
      if (scope.getBinding(localName) !== path.scope.getBinding(localName)) {
        return;
      }
      const operator = path.node.operator.slice(0, -1);
      if (LOGICAL_OPERATORS.includes(operator)) {
        path.replaceWith(logicalExpression(operator, path.node.left, assignmentExpression("=", cloneNode(path.node.left), path.node.right)));
      } else {
        path.node.right = binaryExpression(operator, cloneNode(path.node.left), path.node.right);
        path.node.operator = "=";
      }
    }
  }
};
{
  simpleAssignmentVisitor.UpdateExpression = {
    exit(path) {
      if (!this.includeUpdateExpression) return;
      const {
        scope,
        bindingNames
      } = this;
      const arg = path.get("argument");
      if (!arg.isIdentifier()) return;
      const localName = arg.node.name;
      if (!bindingNames.has(localName)) return;
      if (scope.getBinding(localName) !== path.scope.getBinding(localName)) {
        return;
      }
      if (path.parentPath.isExpressionStatement() && !path.isCompletionRecord()) {
        const operator = path.node.operator == "++" ? "+=" : "-=";
        path.replaceWith(assignmentExpression(operator, arg.node, numericLiteral(1)));
      } else if (path.node.prefix) {
        path.replaceWith(assignmentExpression("=", identifier(localName), binaryExpression(path.node.operator[0], unaryExpression("+", arg.node), numericLiteral(1))));
      } else {
        const old = path.scope.generateUidIdentifierBasedOnNode(arg.node, "old");
        const varName = old.name;
        path.scope.push({
          id: old
        });
        const binary = binaryExpression(path.node.operator[0], identifier(varName), numericLiteral(1));
        path.replaceWith(sequenceExpression([assignmentExpression("=", identifier(varName), unaryExpression("+", arg.node)), assignmentExpression("=", cloneNode(arg.node), binary), identifier(varName)]));
      }
    }
  };
}
function simplifyAccess(path, bindingNames) {
  {
    var _arguments$;
    path.traverse(simpleAssignmentVisitor, {
      scope: path.scope,
      bindingNames,
      seen: new WeakSet(),
      includeUpdateExpression: (_arguments$ = arguments[2]) != null ? _arguments$ : true
    });
  }
}

//# sourceMappingURL=index.js.map