Methods are defined within the context of a struct and their first parameter is always self
Associated functions don’t take self as a parameter
modified: compiler/rustc_typeck/src/check/method/suggest.rs
modified: src/test/ui/auto-ref-slice-plus-ref.stderr
modified: src/test/ui/block-result/issue-3563.stderr
modified: src/test/ui/issues/issue-28344.stderr
modified: src/test/ui/suggestions/dont-suggest-pin-array-dot-set.stderr
modified: src/test/ui/suggestions/suggest-methods.stderr
modified: src/test/ui/traits/trait-upcasting/subtrait-method.stderr
If a symbol name can only be imported from one place for a type, and
as long as it was not glob-imported anywhere in the current crate, we
can trim its printed path and print only the name.
This has wide implications on error messages with types, for example,
shortening `std::vec::Vec` to just `Vec`, as long as there is no other
`Vec` importable anywhere.
This adds a new '-Z trim-diagnostic-paths=false' option to control this
feature.
On the good path, with no diagnosis printed, we should try to avoid
issuing this query, so we need to prevent trimmed_def_paths query on
several cases.
This change also relies on a previous commit that differentiates
between `Debug` and `Display` on various rustc types, where the latter
is trimmed and presented to the user and the former is not.