fix: keep parentheses when the precedence of inner expr is lower than the outer one

[roife]

fix #17185

Additionally, this PR simplifies some code in apply_demorgan.

[roife]

Besides, I'm not sure about the commented-out test:

rust-analyzer/crates/ide-assists/src/handlers/apply_demorgan.rs

Lines 222 to 231 in ef5c6da

	// FIXME : This needs to go.
	// // https://github.com/rust-lang/rust-analyzer/issues/10963
	// #[test]
	// fn demorgan_doesnt_hang() {
	// check_assist(
	// apply_demorgan,
	// "fn f() { 1 || 3 &&$0 4 || 5 }",
	// "fn f() { !(!1 || !3 || !4) || 5 }",
	// )
	// }

1 || 3 &&$0 4 || 5 should be transformed into 1 || !(!3 || !4) || 5 (just as the assist does currently) instead of !(!1 || !3 || !4) || 5. Perhaps we should update the test and uncomment it.

[alibektas]

Besides, I'm not sure about the commented-out test:

rust-analyzer/crates/ide-assists/src/handlers/apply_demorgan.rs

Lines 222 to 231 in ef5c6da

	// FIXME : This needs to go.
	// // https://github.com/rust-lang/rust-analyzer/issues/10963
	// #[test]
	// fn demorgan_doesnt_hang() {
	// check_assist(
	// apply_demorgan,
	// "fn f() { 1 || 3 &&$0 4 || 5 }",
	// "fn f() { !(!1 || !3 || !4) || 5 }",
	// )
	// }

1 || 3 &&$0 4 || 5 should be transformed into 1 || !(!3 || !4) || 5 (just as the assist does currently) instead of !(!1 || !3 || !4) || 5. Perhaps we should update the test and uncomment it.

Yes we can do definitely do that.

[Veykril]

Thanks!
@bors r+

[bors]

📌 Commit 4ada826 has been approved by Veykril

It is now in the queue for this repository.

[bors]

⌛ Testing commit 4ada826 with merge 7aecf1a...

[bors]

☀️ Test successful - checks-actions
Approved by: Veykril
Pushing 7aecf1a to master...