Invalid UpdateExpression's arguments
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Description
Invalid UpdateExpression's arguments
Esprima' UpdateExpression's argument is one of: ObjectExpression, ArrayExpression, MemberExpression, Identifier.
Consider behaviour of V8:

Should be:
Argument of UpdateExpression is one of: Identifier, MemberExpression
Steps to reproduce
esprima.parse('--[]') // or --{}, []--, (++[]), etc.
Expected output
Expected "Invalid left-hand side expression in prefix operation"
Actual output
{
"type": "UpdateExpression",
"operator": "--",
"argument": {
"type": "ArrayExpression",
"elements": []
},
"prefix": true
}
Relevant references
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First steps
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Research direction
No source file or test is named in the issue. Reproduce the listed --[] and --{} cases in Esprima, locate the UpdateExpression parser entry point, and compare its accepted argument types with the expected syntax error. Done means invalid operands are rejected while Identifier and MemberExpression operands still parse.
Written by the indexing model from the issue text.
Assessment
- Tech stack
- javascript, typescript
- Domain
- compilers
- Issue type
- Bug
- Difficulty
- 3/5
- Estimated time
- 1-2 days
- Activity status
- Stale
- Clarity
- Mostly clear
- Newbie friendliness
- 45/100