pub fn multispan_sugg<I>(diag: &mut Diagnostic, help_msg: &str, sugg: I)where
    I: IntoIterator<Item = (Span, String)>,
Expand description

Create a suggestion made from several span → replacement.

Note: in the JSON format (used by compiletest_rs), the help message will appear once per replacement. In human-readable format though, it only appears once before the whole suggestion.