diff options
Diffstat (limited to 'src/test')
| -rw-r--r-- | src/test/ui/drop/dropck_legal_cycles.rs | 14 | ||||
| -rw-r--r-- | src/test/ui/issues/issue-30371.rs | 1 | ||||
| -rw-r--r-- | src/test/ui/lint/for_loop_over_fallibles.rs | 43 | ||||
| -rw-r--r-- | src/test/ui/lint/for_loop_over_fallibles.stderr | 101 |
4 files changed, 152 insertions, 7 deletions
diff --git a/src/test/ui/drop/dropck_legal_cycles.rs b/src/test/ui/drop/dropck_legal_cycles.rs index 27a599315dc..6a0fe7784fb 100644 --- a/src/test/ui/drop/dropck_legal_cycles.rs +++ b/src/test/ui/drop/dropck_legal_cycles.rs @@ -1017,7 +1017,7 @@ impl<'a> Children<'a> for HM<'a> { where C: Context + PrePost<Self>, Self: Sized { if let Some(ref hm) = self.contents.get() { - for (k, v) in hm.iter().nth(index / 2) { + if let Some((k, v)) = hm.iter().nth(index / 2) { [k, v][index % 2].descend_into_self(context); } } @@ -1032,7 +1032,7 @@ impl<'a> Children<'a> for VD<'a> { where C: Context + PrePost<Self>, Self: Sized { if let Some(ref vd) = self.contents.get() { - for r in vd.iter().nth(index) { + if let Some(r) = vd.iter().nth(index) { r.descend_into_self(context); } } @@ -1047,7 +1047,7 @@ impl<'a> Children<'a> for VM<'a> { where C: Context + PrePost<VM<'a>> { if let Some(ref vd) = self.contents.get() { - for (_idx, r) in vd.iter().nth(index) { + if let Some((_idx, r)) = vd.iter().nth(index) { r.descend_into_self(context); } } @@ -1062,7 +1062,7 @@ impl<'a> Children<'a> for LL<'a> { where C: Context + PrePost<LL<'a>> { if let Some(ref ll) = self.contents.get() { - for r in ll.iter().nth(index) { + if let Some(r) = ll.iter().nth(index) { r.descend_into_self(context); } } @@ -1077,7 +1077,7 @@ impl<'a> Children<'a> for BH<'a> { where C: Context + PrePost<BH<'a>> { if let Some(ref bh) = self.contents.get() { - for r in bh.iter().nth(index) { + if let Some(r) = bh.iter().nth(index) { r.descend_into_self(context); } } @@ -1092,7 +1092,7 @@ impl<'a> Children<'a> for BTM<'a> { where C: Context + PrePost<BTM<'a>> { if let Some(ref bh) = self.contents.get() { - for (k, v) in bh.iter().nth(index / 2) { + if let Some((k, v)) = bh.iter().nth(index / 2) { [k, v][index % 2].descend_into_self(context); } } @@ -1107,7 +1107,7 @@ impl<'a> Children<'a> for BTS<'a> { where C: Context + PrePost<BTS<'a>> { if let Some(ref bh) = self.contents.get() { - for r in bh.iter().nth(index) { + if let Some(r) = bh.iter().nth(index) { r.descend_into_self(context); } } diff --git a/src/test/ui/issues/issue-30371.rs b/src/test/ui/issues/issue-30371.rs index a1ae9a36bc1..eea548c482f 100644 --- a/src/test/ui/issues/issue-30371.rs +++ b/src/test/ui/issues/issue-30371.rs @@ -1,5 +1,6 @@ // run-pass #![allow(unreachable_code)] +#![allow(for_loops_over_fallibles)] #![deny(unused_variables)] fn main() { diff --git a/src/test/ui/lint/for_loop_over_fallibles.rs b/src/test/ui/lint/for_loop_over_fallibles.rs new file mode 100644 index 00000000000..43d71c2e808 --- /dev/null +++ b/src/test/ui/lint/for_loop_over_fallibles.rs @@ -0,0 +1,43 @@ +// check-pass + +fn main() { + // Common + for _ in Some(1) {} + //~^ WARN for loop over an `Option`. This is more readably written as an `if let` statement + //~| HELP to check pattern in a loop use `while let` + //~| HELP consider using `if let` to clear intent + for _ in Ok::<_, ()>(1) {} + //~^ WARN for loop over a `Result`. This is more readably written as an `if let` statement + //~| HELP to check pattern in a loop use `while let` + //~| HELP consider using `if let` to clear intent + + // `Iterator::next` specific + for _ in [0; 0].iter().next() {} + //~^ WARN for loop over an `Option`. This is more readably written as an `if let` statement + //~| HELP to iterate over `[0; 0].iter()` remove the call to `next` + //~| HELP consider using `if let` to clear intent + + // `Result<impl Iterator, _>`, but function doesn't return `Result` + for _ in Ok::<_, ()>([0; 0].iter()) {} + //~^ WARN for loop over a `Result`. This is more readably written as an `if let` statement + //~| HELP to check pattern in a loop use `while let` + //~| HELP consider using `if let` to clear intent +} + +fn _returns_result() -> Result<(), ()> { + // `Result<impl Iterator, _>` + for _ in Ok::<_, ()>([0; 0].iter()) {} + //~^ WARN for loop over a `Result`. This is more readably written as an `if let` statement + //~| HELP to check pattern in a loop use `while let` + //~| HELP consider unwrapping the `Result` with `?` to iterate over its contents + //~| HELP consider using `if let` to clear intent + + // `Result<impl IntoIterator>` + for _ in Ok::<_, ()>([0; 0]) {} + //~^ WARN for loop over a `Result`. This is more readably written as an `if let` statement + //~| HELP to check pattern in a loop use `while let` + //~| HELP consider unwrapping the `Result` with `?` to iterate over its contents + //~| HELP consider using `if let` to clear intent + + Ok(()) +} diff --git a/src/test/ui/lint/for_loop_over_fallibles.stderr b/src/test/ui/lint/for_loop_over_fallibles.stderr new file mode 100644 index 00000000000..96efdf85c49 --- /dev/null +++ b/src/test/ui/lint/for_loop_over_fallibles.stderr @@ -0,0 +1,101 @@ +warning: for loop over an `Option`. This is more readably written as an `if let` statement + --> $DIR/for_loop_over_fallibles.rs:5:14 + | +LL | for _ in Some(1) {} + | ^^^^^^^ + | + = note: `#[warn(for_loops_over_fallibles)]` on by default +help: to check pattern in a loop use `while let` + | +LL | while let Some(_) = Some(1) {} + | ~~~~~~~~~~~~~~~ ~~~ +help: consider using `if let` to clear intent + | +LL | if let Some(_) = Some(1) {} + | ~~~~~~~~~~~~ ~~~ + +warning: for loop over a `Result`. This is more readably written as an `if let` statement + --> $DIR/for_loop_over_fallibles.rs:9:14 + | +LL | for _ in Ok::<_, ()>(1) {} + | ^^^^^^^^^^^^^^ + | +help: to check pattern in a loop use `while let` + | +LL | while let Ok(_) = Ok::<_, ()>(1) {} + | ~~~~~~~~~~~~~ ~~~ +help: consider using `if let` to clear intent + | +LL | if let Ok(_) = Ok::<_, ()>(1) {} + | ~~~~~~~~~~ ~~~ + +warning: for loop over an `Option`. This is more readably written as an `if let` statement + --> $DIR/for_loop_over_fallibles.rs:15:14 + | +LL | for _ in [0; 0].iter().next() {} + | ^^^^^^^^^^^^^^^^^^^^ + | +help: to iterate over `[0; 0].iter()` remove the call to `next` + | +LL | for _ in [0; 0].iter().by_ref() {} + | ~~~~~~~~~ +help: consider using `if let` to clear intent + | +LL | if let Some(_) = [0; 0].iter().next() {} + | ~~~~~~~~~~~~ ~~~ + +warning: for loop over a `Result`. This is more readably written as an `if let` statement + --> $DIR/for_loop_over_fallibles.rs:21:14 + | +LL | for _ in Ok::<_, ()>([0; 0].iter()) {} + | ^^^^^^^^^^^^^^^^^^^^^^^^^^ + | +help: to check pattern in a loop use `while let` + | +LL | while let Ok(_) = Ok::<_, ()>([0; 0].iter()) {} + | ~~~~~~~~~~~~~ ~~~ +help: consider using `if let` to clear intent + | +LL | if let Ok(_) = Ok::<_, ()>([0; 0].iter()) {} + | ~~~~~~~~~~ ~~~ + +warning: for loop over a `Result`. This is more readably written as an `if let` statement + --> $DIR/for_loop_over_fallibles.rs:29:14 + | +LL | for _ in Ok::<_, ()>([0; 0].iter()) {} + | ^^^^^^^^^^^^^^^^^^^^^^^^^^ + | +help: to check pattern in a loop use `while let` + | +LL | while let Ok(_) = Ok::<_, ()>([0; 0].iter()) {} + | ~~~~~~~~~~~~~ ~~~ +help: consider unwrapping the `Result` with `?` to iterate over its contents + | +LL | for _ in Ok::<_, ()>([0; 0].iter())? {} + | + +help: consider using `if let` to clear intent + | +LL | if let Ok(_) = Ok::<_, ()>([0; 0].iter()) {} + | ~~~~~~~~~~ ~~~ + +warning: for loop over a `Result`. This is more readably written as an `if let` statement + --> $DIR/for_loop_over_fallibles.rs:36:14 + | +LL | for _ in Ok::<_, ()>([0; 0]) {} + | ^^^^^^^^^^^^^^^^^^^ + | +help: to check pattern in a loop use `while let` + | +LL | while let Ok(_) = Ok::<_, ()>([0; 0]) {} + | ~~~~~~~~~~~~~ ~~~ +help: consider unwrapping the `Result` with `?` to iterate over its contents + | +LL | for _ in Ok::<_, ()>([0; 0])? {} + | + +help: consider using `if let` to clear intent + | +LL | if let Ok(_) = Ok::<_, ()>([0; 0]) {} + | ~~~~~~~~~~ ~~~ + +warning: 6 warnings emitted + |