checker: abstract repetitive error handling

[ttytm]

🤖 Generated by Copilot at 569b52a

This pull request refactors and simplifies the error reporting and checking logic for various expressions involving stack objects, or blocks, ? and ! operators in the V compiler. It extracts two common functions expr_or_block_err and fail_if_stack_struct_action_outside_unsafe in vlib/v/checker/checker.v and reuses them in other modules. It also updates the error messages and the corresponding tests to be more specific and consistent.

🤖 Generated by Copilot at 569b52a

• Extract common logic for checking if an identifier refers to a stack object that cannot be assigned outside unsafe blocks to a new function fail_if_stack_sturct_action_outside_unsafe in vlib/v/checker/checker.v (link, link)
• Use the new function fail_if_stack_sturct_action_outside_unsafe to simplify the code in vlib/v/checker/assign.v, vlib/v/checker/return.v, and vlib/v/checker/struct.v (link, link)
• Add a new function expr_or_block_err in vlib/v/checker/checker.v that handles the error reporting for unexpected or blocks, ? and ! operators when the expression is not an Option or a Result (link)
• Use the new function expr_or_block_err to simplify the code and improve the error messages in vlib/v/checker/checker.v for function call expressions, selector expressions, go statements, and struct init expressions (link, link, link, link)
• Update the expected output of the tests in vlib/v/checker/tests/go_wait_or.out, vlib/v/checker/tests/struct_field_option_err.out, and vlib/v/checker/tests/unexpected_or_propagate.out to match the new error messages generated by the new function expr_or_block_err (link, link, link, link)

[ttytm]

The error handlers already had explicitly checked if we .propagate_option or .propagate_result.

I assume we therefore don't need the or a Result. Other errors already have taken that into account and ended with just an Option. It was just this error that went out of the line.

[ttytm]

Due to the abstraction this was adapted to be uniform with the predominantly used phrasing is not ...

[JalonSolov]

The or a Result phrasing is likely left over from when ? meant both.

As long as the error matches the type... is not an Option or is not a Result.

[spytheman]

Good work.