| // Copyright 2019 Google, Inc. All rights reserved. | |
| // This code is governed by the BSD license found in the LICENSE file. | |
| /*--- | |
| esid: prod-OptionalExpression | |
| description: > | |
| optional chaining is forbidden in write contexts | |
| info: | | |
| UpdateExpression[Yield, Await]: | |
| LeftHandSideExpression++ | |
| LeftHandSideExpression-- | |
| ++UnaryExpression | |
| --UnaryExpression | |
| features: [optional-chaining] | |
| negative: | |
| type: SyntaxError | |
| phase: parse | |
| ---*/ | |
| $DONOTEVALUATE(); | |
| // --UnaryExpression | |
| const a = {}; | |
| --a?.b; |