error: expected `,`, found `.`
 --> tests/ui/expression-fallback.rs:4:11
  |
4 | #[error("".yellow)]
  |           ^ expected `,`

error: argument never used
 --> tests/ui/expression-fallback.rs:4:12
  |
4 | #[error("".yellow)]
  |         -- ^^^^^^ argument never used
  |         |
  |         formatting specifier missing

error[E0425]: cannot find value `yellow` in this scope
 --> tests/ui/expression-fallback.rs:4:12
  |
4 | #[error("".yellow)]
  |            ^^^^^^ not found in this scope