Less import overhead for errors

[est31]

This removes huge (3+ lines) import lists found in files that had their error reporting migrated. These lists are bad for developer workflows as adding, removing, or editing a single error's name might cause a chain reaction that bloats the git diff. As the error struct names are long, the likelihood of such chain reactions is high.

Follows the suggestion by @Nilstrieb in the zulip thread to replace the use errors::{FooErr, BarErr}; with use errors; and then changing to errors::FooErr on the usage sites.

I have used sed to do most of the changes, i.e. something like:

sed -i -E 's/(create_err|create_feature_err|emit_err|create_note|emit_fatal|emit_warning)\(([[:alnum:]]+|[A-Z][[:alnum:]:]*)( \{|\))/\1(errors::\2\3/' path/to/file.rs

& then I manually fixed the errors that occured. Most manual changes were required in compiler/rustc_parse/src/parser/expr.rs.

r? @compiler-errors

[compiler-errors]

Cool, thanks @est31 for doing this.

@bors r+ p=1

[bors]

📌 Commit 580cc89 has been approved by compiler-errors

It is now in the queue for this repository.

[bors]

⌛ Testing commit 580cc89 with merge 7f97aea...

[bors]

☀️ Test successful - checks-actions
Approved by: compiler-errors
Pushing 7f97aea to master...

[bors]

☀️ Test successful - checks-actions
Approved by: compiler-errors
Pushing 7f97aea to master...

[rust-timer]

Finished benchmarking commit (7f97aea): comparison URL.

Overall result: ❌✅ regressions and improvements - ACTION NEEDED

Next Steps: If you can justify the regressions found in this perf run, please indicate this with @rustbot label: +perf-regression-triaged along with sufficient written justification. If you cannot justify the regressions please open an issue or create a new PR that fixes the regressions, add a comment linking to the newly created issue or PR, and then add the perf-regression-triaged label to this PR.

@rustbot label: +perf-regression
cc @rust-lang/wg-compiler-performance

Instruction count

This is a highly reliable metric that was used to determine the overall result at the top of this comment.

	mean	range	count
Regressions ❌ (primary)	0.4%	[0.3%, 0.5%]	2
Regressions ❌ (secondary)	0.9%	[0.3%, 1.3%]	11
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-0.7%	[-0.7%, -0.7%]	2
All ❌✅ (primary)	0.4%	[0.3%, 0.5%]	2

Max RSS (memory usage)

Results

This is a less reliable metric that may be of interest but was not used to determine the overall result at the top of this comment.

	mean	range	count
Regressions ❌ (primary)	-	-	0
Regressions ❌ (secondary)	2.4%	[2.3%, 2.5%]	3
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-3.4%	[-6.0%, -2.5%]	4
All ❌✅ (primary)	-	-	0

Cycles

Results

This is a less reliable metric that may be of interest but was not used to determine the overall result at the top of this comment.

	mean	range	count
Regressions ❌ (primary)	-	-	0
Regressions ❌ (secondary)	-	-	0
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-4.8%	[-4.9%, -4.6%]	2
All ❌✅ (primary)	-	-	0

[lqd]

This is of course noise, and has corrected in #102842 (comment)

@rustbot label: +perf-regression-triaged