---
source: crates/rolldown_testing/src/integration_test.rs
---
# Errors
## PARSE_ERROR
```text
[PARSE_ERROR] Identifier `DROP` has already been declared
╭─[ identity-last.js:1:10 ]
│
1 │ function DROP(x) { return [x] }
│ ──┬─
│ ╰─── `DROP` has already been declared here
2 │ function DROP(x) { return x }
│ ──┬─
│ ╰─── It can not be redeclared here
───╯
```
## PARSE_ERROR
```text
[PARSE_ERROR] Identifier `keep` has already been declared
╭─[ identity-first.js:1:10 ]
│
1 │ function keep(x) { return x }
│ ──┬─
│ ╰─── `keep` has already been declared here
2 │ function keep(x) { return [x] }
│ ──┬─
│ ╰─── It can not be redeclared here
───╯
```