TypeScript
TypeScript found an argument that is not assignable to the parameter type
error TS2345: Argument of type 'X' is not assignable to parameter of type 'Y'.
TypeScript rejected a function call because one of the provided arguments does not match the type expected by the target parameter.
Observed message
error TS2345: Argument of type 'X' is not assignable to parameter of type 'Y'.
Why it happens
- The argument value has a different shape or primitive type than the function expects.
- A union or generic value is broader than the accepted parameter type.
- The function signature changed but the calling code was not updated.
How to fix it
- Inspect the function signature and compare it with the value being passed.
- Transform or narrow the argument before calling the function if needed.
- Only broaden the function signature if the wider input is genuinely valid.
