Add suspicious_open_options lint. #11608

Checks for the suspicious use of OpenOptions::create() without an explicit OpenOptions::truncate(). create() alone will either create a new file or open an existing file. If the file already exists, it will be overwritten when written to, but the file will not be truncated by default. If less data is written to the file than it already contains, the remainder of the file will remain unchanged, and the end of the file will contain old data. In most cases, one should either use `create_new` to ensure the file is created from scratch, or ensure `truncate` is called so that the truncation behaviour is explicit. `truncate(true)` will ensure the file is entirely overwritten with new data, whereas `truncate(false)` will explicitely keep the default behavior. ```rust use std::fs::OpenOptions; OpenOptions::new().create(true).truncate(true); ```

Also rebase and fix conflicts

- New ineffective_open_options had to be fixed. - Now not raising an issue on missing `truncate` when `append(true)` makes the intent clear. - Try implementing more advanced tests for non-chained operations. Fail

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Add suspicious_open_options lint. #11608

Add suspicious_open_options lint. #11608

Commits on Jan 15, 2024