Implement code action to ignore unused Result value #3255
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Thank you! Fab work here!
We can avoid traversing the AST as the location of the discarded result is contained by the warning that would have been emitted during compilation. There's 2 ways we could get this information:
- Replace the warning emitter trait with just a vec of warnings that gets appended to. Then the language server can iterate over the vec once to see if there's any code actions it should offer. This is the best solution.
- Have the analyser also record the location of unused warnings in the analysed module data and have the language server use this data. This would be a temporary solution, but we already do something like this for unused imports.
Either of these approached would be fab.
| let range = (start as usize)..(end as usize); | ||
| offset += end - start; | ||
| offset -= edit.new_text.len() as u32; | ||
| offset += end - start - edit.new_text.len() as i32; |
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Revert this please, this old version has it has a bug in it 🙏
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The way it was before with offset being a u32, the subtraction on line 100 would panic with an integer underflow if the code action added more characters than it removed. I'm not sure how else to solve this. What exactly is the bug?
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It would not apply the text edit correctly. The underflow likely means you have a bug and are trying to remove more content than exists.
Closes #2960
My first contribution, please be gentle :3
I had to undo the changes from commit 64924b9 as my tests would otherwise panic with an integer underflow. I'm not really sure why it was necessary in the first place, maybe @giacomocavalieri can help?