[NLL] Returns are interesting for free regions
Based on #53088 - creating now to get feedback.
Closes#51175
* Make assigning to the return type interesting.
* Use "returning this value" instead of "return" in error messages.
* Prefer one of the explanations that we have a name for to a generic interesting cause in some cases.
* Treat causes that involve the destination of a call like assignments.
Make some ported cfail tests robust w.r.t. NLL
Updated the most glaring instances of weak tests w.r.t. NLL that came from #53196.
See also the bulletpoint list on #53351.
Rollup of 11 pull requests
Successful merges:
- #52858 (Implement Iterator::size_hint for Elaborator.)
- #53321 (Fix usage of `wasm_target_feature`)
- #53326 ([nll] add regression test for issue #27868)
- #53347 (rustc_resolve: don't allow paths starting with `::crate`.)
- #53349 ([nll] add tests for #48697 and #30104)
- #53357 (Pretty print btreemap for GDB)
- #53358 (`{to,from}_{ne,le,be}_bytes` for unsigned integer types)
- #53406 (Do not suggest conversion method that is already there)
- #53407 (make more ported compile fail tests more robust w.r.t. NLL)
- #53413 (Warn that `#![feature(rust_2018_preview)]` is implied when the edition is set to Rust 2018.)
- #53434 (wasm: Remove --strip-debug argument to LLD)
Failed merges:
r? @ghost
make more ported compile fail tests more robust w.r.t. NLL
This is similar to PR #53369, except it covers a disjoint (and much smaller) set of tests that I needed to look at more carefully before being 100% certain they were the same kind of issue.
[nll] add tests for #48697 and #30104
Adds tests for the following issues:
- #48697 ``[NLL] ICE: unexpected region for local data with reference to closure``
- #30104 ``Destructuring boxes into multiple mutable references seems broken``
r? @nikomatsakis
[nll] add regression test for issue #27868
Adds a test for #27868 ``Inconsistent evaluation order for assignment operations``
apart of #47366 ``tracking issue for bugs fixed by the MIR borrow checker or NLL``
r? @nikomatsakis
compile-fail-fulldeps/proc-macro/proc-macro-attributes.rs - resolution change for derive helper attributes with the same name as derive itself
run-pass/macro-comma-support.rs - indeterminate resolutions for macros in expression positions
ui/issues/issue-49074.rs - diagnostics regression, not enough recovery to report the second error
ui/object-lifetime/object-lifetime-default.stderr - unstable diagnostics?
rustc_resolve: overhaul `#![feature(uniform_paths)]` error reporting.
Fixes#53408 by only considering external crates to conflict within their (type/module) namespace, *not* with the value or macro namespaces, and also by adding a special-cased error for redundant `use crate_name;` imports (without actually allowing them).
Also, all canaries for a given import are grouped into one diagnostic per namespace, in order to make block-scoped ambiguities clearer.
See changed/added tests for more details.
r? @petrochenkov cc @aturon @joshtriplett
syntax_ext: remove leftover span_err_if_not_stage0 macro.
I believe this is the right fix for #53380, although I'm not sure what happened.
My guess is this copy of the macro was accidentally missed when others were removed?
cc @matthewjasper @varkor (please do not put this in a rollup, in case it fails)
Addressed #51602Fixed#51602
r? @estebank
here I have addressed the case where `in` was not expected right after `if` block. Speaking of `type ascription` I am not sure if this the best approach which I have implemented. Plus I think one more test case can be added to test `type-ascription` case, though I don't have any at this point of time. I will ping you again if all existing testcases pass.
Don't accept non-string literals for the format string in writeln
This is to improve diagnostics.
`println` and `eprintln` were already fixed by #52394.
Fixes#30143
For move errors, suggest match ergonomics instead of `ref`
Partially fixes issue #52423. Also makes errors and suggestions more consistent between move-from-place and move-from-value errors.
Limitations:
- Only the first pattern in a match arm can have a "consider removing this borrow operator" suggestion.
- Suggestions don't always compile as-is (see the TODOs in the test for details).
Sorry for the really long test. I wanted to make sure I handled every case I could think of, and it turned out there were a lot of them.
Questions:
- Is there any particular applicability I should set on those suggestions?
- Are the notes about the `Copy` trait excessive?
