Add and use generics.is_empty() and generics.is_own_empty, rather than using generics' attributes

[spastorino]

r? @compiler-errors

Related to #123929

[rustbot]

HIR ty lowering was modified

cc @fmease

Some changes occurred in src/tools/rustfmt

cc @rust-lang/rustfmt

Some changes occurred in src/tools/clippy

cc @rust-lang/clippy

[compiler-errors]

Please fix clippy and rustfmt, otherwise looks fine. I will review again when it's fixed.

[spastorino]

Please fix clippy and rustfmt, otherwise looks fine. I will review again when it's fixed.

Not sure what do you mean by fix clippy. About rustfmt is fixed, didn't realize rustfmt was using ast::Generics.

[spastorino]

@rustbot review

[bors]

☔ The latest upstream changes (presumably #125257) made this pull request unmergeable. Please resolve the merge conflicts.

[compiler-errors]

@bors r+

[bors]

📌 Commit 4501ae8 has been approved by compiler-errors

It is now in the queue for this repository.

[bors]

⌛ Testing commit 4501ae8 with merge 1d1283e...

[bors]

☀️ Test successful - checks-actions
Approved by: compiler-errors
Pushing 1d1283e to master...

[rust-timer]

Finished benchmarking commit (1d1283e): comparison URL.

Overall result: ✅ improvements - no action needed

@rustbot label: -perf-regression

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
Regressions ❌ (secondary)	-	-	0
Improvements ✅ (primary)	-0.3%	[-0.3%, -0.3%]	1
Improvements ✅ (secondary)	-1.4%	[-1.4%, -1.4%]	1
All ❌✅ (primary)	-0.3%	[-0.3%, -0.3%]	1

Max RSS (memory usage)

Results (primary -2.0%)

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)	-2.0%	[-2.0%, -2.0%]	1
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	-2.0%	[-2.0%, -2.0%]	1

Cycles

Results (secondary -3.0%)

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)	-3.0%	[-5.4%, -1.5%]	15
All ❌✅ (primary)	-	-	0

Binary size

This benchmark run did not return any relevant results for this metric.

Bootstrap: 669.813s -> 668.514s (-0.19%)
Artifact size: 316.18 MiB -> 316.20 MiB (0.01%)