dart-fix-runtime-errors

Run dart fix --dry-run to preview automated corrections, then dart fix --apply to apply them. Remaining errors that automated fixes cannot handle must be resolved manually based on their error type, such as null safety or type mismatch issues.

Determine whether the variable can logically be null. If yes, use optional chaining (?.) or a fallback (??). If initialization is guaranteed elsewhere but not provable by the compiler, mark the declaration with the late keyword.

Dart's sound type system prevents implicit downcasts from dynamic. Fix it by adding explicit generic type annotations at instantiation, such as <int>[] instead of [], or use an explicit cast after verifying the runtime type.

No. Catch Exception subtypes for recoverable failures only. Error subtypes like TypeError and ArgumentError indicate programming bugs that must be fixed, not caught. Enable the avoid_catching_errors linter rule to enforce this.

Use covariant when a subclass method intentionally tightens a parameter type compared to the overridden superclass method. Without it, tightening parameter types violates contravariance rules and fails static analysis.