remove redundent "<>" for ty::Slice with reference type

[lyming2007]

this fix #103271

[rustbot]

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[fee1-dead]

There might be a better way. AFAICT this diagnostic is erroneous because the span it covers does not contain the angle brackets, so it prints the suggestion on [_] instead of <[_]>. I believe this can be done pretty cheaply using span_to_source, skipping white space and enlarging the span if you see angle brackets from both sides.

[lyming2007]

There might be a better way. AFAICT this diagnostic is erroneous because the span it covers does not contain the angle brackets, so it prints the suggestion on [_] instead of <[_]>. I believe this can be done pretty cheaply using span_to_source, skipping white space and enlarging the span if you see angle brackets from both sides.

pushed a new fix by seeing angle brackets from both sides.

[fee1-dead]

One last nit. Should be good to go after this.

[fee1-dead]

Looks good to me, thanks for this PR!

@bors r+

[bors]

📌 Commit 868ccd5 has been approved by fee1-dead

It is now in the queue for this repository.

[Dylan-DPC]

failed in rollup

@bors r-

[lyming2007]

@fee1-dead should I do something for the merging conflict? This is the first time I encounter this type of conflict

[Dylan-DPC]

What merging conflict? I don't see any conflict in your PR.

[lyming2007]

failed in rollup

failed in rollup

It says failed in #103921 (comment)

[Dylan-DPC]

yes it means your pr failed some tests when it was rolled up. You should see the failures in the error log (after a bit of scrolling ;P). You need to update those tests and then we can merge this again

[lyming2007]

yes it means your pr failed some tests when it was rolled up. You should see the failures in the error log (after a bit of scrolling ;P). You need to update those tests and then we can merge this again

I changed according to that error log. But the CI didn't pass:

---- [ui] src/test/ui/type/issue-103271.rs stdout ----
diff of stderr:

7	   = note: the following trait bounds were not satisfied:
8	           `&[_]: ExactSizeIterator`
9	           which is required by `&mut &[_]: ExactSizeIterator`
+	   = help: items from traits can only be used if the trait is in scope
+	help: the following trait is implemented but not in scope; perhaps add a `use` for it:
+	   |
+	LL | use object::read::read_ref::ReadRef;
+	   |
10	help: the function `len` is implemented on `[_]`
11	   |
12	LL |     let length = <[_]>::len;

[lyming2007]

yes it means your pr failed some tests when it was rolled up. You should see the failures in the error log (after a bit of scrolling ;P). You need to update those tests and then we can merge this again

I think my last code should fix the in the error log. can you merge it again?

[lyming2007]

@Dylan-DPC any progress on it?

[Dylan-DPC]

The CI doesn't seem to pass though? let me rerun it. Also i would wait for @fee1-dead 's confirmation whether it is fine to be merged again or not

[lyming2007]

in the error log

I fixed it according to the error of this log error log
which seems conflict with the CI in PR #103675

[GuillaumeGomez]

Failed in #104151.

@bors r-

[lyming2007]

the test in https://github.com/rust-lang-ci/rust/actions/runs/3420197276/jobs/5694702753 failed as I mentioned before:

failures:

---- [ui] src/test/ui/type/issue-103271.rs stdout ----
diff of stderr:

7	   = note: the following trait bounds were not satisfied:
8	           `&[_]: ExactSizeIterator`
9	           which is required by `&mut &[_]: ExactSizeIterator`
-	   = help: items from traits can only be used if the trait is in scope
-	help: the following trait is implemented but not in scope; perhaps add a `use` for it:
-	   |
-	LL | use object::read::read_ref::ReadRef;
-	   |
15	help: the function `len` is implemented on `[_]`
16	   |
17	LL |     let length = <[_]>::len;

but if I removed these code:

-	   = help: items from traits can only be used if the trait is in scope
-	help: the following trait is implemented but not in scope; perhaps add a `use` for it:
-	   |
-	LL | use object::read::read_ref::ReadRef;
-	   |

This CI would fail at:

---- [ui] src/test/ui/type/issue-103271.rs stdout ----
diff of stderr:

7	   = note: the following trait bounds were not satisfied:
8	           `&[_]: ExactSizeIterator`
9	           which is required by `&mut &[_]: ExactSizeIterator`
+	   = help: items from traits can only be used if the trait is in scope
+	help: the following trait is implemented but not in scope; perhaps add a `use` for it:
+	   |
+	LL | use object::read::read_ref::ReadRef;
+	   |
10	help: the function `len` is implemented on `[_]`
11	   |
12	LL |     let length = <[_]>::len;

@fee1-dead

[fee1-dead]

I asked on Zulip, and this is #26454. The solution here is to use another function name that does not have the suggestion.

[lyming2007]

@fee1-dead should be ok now. please approve it again. :)

[fee1-dead]

@bors r+

[bors]

📌 Commit 0b6934d has been approved by fee1-dead

It is now in the queue for this repository.