Linking to discussions from pre-1.0 does not help your assertion.
std::fs::File's impl of std::io::Read:
https://github.com/rust-lang/rust/blob/7fc048f0712ba515ca11f...
-> https://github.com/rust-lang/rust/blob/7fc048f0712ba515ca11f...
-> https://github.com/rust-lang/rust/blob/7fc048f0712ba515ca11f...
Again, as I said, it corresponds one-to-one with a call to the underlying read API. The retries for ErrorKind::Interrupted are done by higher abstractions like std::io::Read::read_exact, and they explicitly document that they do this.
https://github.com/rust-lang/rust/blob/7fc048f0712ba515ca11f...