Use free regions when determining self type in compare_impl_method

[sapphire-arches]

The ExplicitSelf::determine function expects to be able to compare regions. However, when the compare_self_type error reporting code runs we haven't resolved bound regions yet. Thus we replace them with free regions first. Fixes#48276

[rust-highfive]

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[emilyalbini]

Thanks for the PR @bobtwinkles, the release team will periodically make sure this PR gets reviewed.

@nikomatsakis, this PR needs your review!

[nikomatsakis]

@bors r+

[bors]

📌 Commit 9882050 has been approved by nikomatsakis

[Manishearth]

I get a failure on this in the rollup

[01:00:19] failures:
[01:00:19] [01:00:19] ---- [ui] ui/issue-48276.rs stdout ----
[01:00:19] diff of stderr:
[01:00:19] [01:00:19] 1	error[E0185]: method `from` has a `&self` declaration in the impl, but not in the trait
[01:00:19] 2 --> $DIR/issue-48276.rs:21:5
[01:00:19] 3 |
[01:00:19] -	15 | fn from(a: A) -> Self;
[01:00:19] +	LL | fn from(a: A) -> Self;
[01:00:19] 5 | ---------------------- trait method declared without `&self`
[01:00:19] 6	...
[01:00:19] -	21 | fn from(self: &'a Self) -> &'b str {
[01:00:19] +	LL | fn from(self: &'a Self) -> &'b str {
[01:00:19] 8 | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ `&self` used in impl
[01:00:19] 9 [01:00:19] 10	error[E0185]: method `from` has a `&self` declaration in the impl, but not in the trait
[01:00:19] [01:00:19] 11 --> $DIR/issue-48276.rs:30:5
[01:00:19] 12 |
[01:00:19] -	30 | fn from(&self) -> B {
[01:00:19] +	LL | fn from(&self) -> B {
[01:00:19] 14 | ^^^^^^^^^^^^^^^^^^^ `&self` used in impl
[01:00:19] 15 |
[01:00:19] 16 = note: `from` from trait: `fn(T) -> Self`
[01:00:19] [01:00:19] 18	error[E0185]: method `from` has a `&self` declaration in the impl, but not in the trait
[01:00:19] 19 --> $DIR/issue-48276.rs:37:5
[01:00:19] 20 |
[01:00:19] -	37 | fn from(&self) -> &'static str {
[01:00:19] +	LL | fn from(&self) -> &'static str {
[01:00:19] 22 | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ `&self` used in impl
[01:00:19] 23 |
[01:00:19] 24 = note: `from` from trait: `fn(T) -> Self`
[01:00:19] [01:00:19] 25 [01:00:19] 26	error: aborting due to 3 previous errors
[01:00:19] 27 [01:00:19] +	If you want more information on this error, try using "rustc --explain E0185"
[01:00:19] 28 [01:00:19] [01:00:19] [01:00:19] The actual stderr differed from the expected stderr.
[01:00:19] Actual stderr saved to /checkout/obj/build/x86_64-unknown-linux-gnu/test/ui/issue-48276.stderr
[01:00:19] To update references, run this command from build directory:
[01:00:19] /checkout/src/test/ui/update-references.sh '/checkout/obj/build/x86_64-unknown-linux-gnu/test/ui' 'issue-48276.rs'
[01:00:19] [01:00:19] error: 1 errors occurred comparing output.
[01:00:19] status: exit code: 101
[01:00:19] stdout:
[01:00:19] ------------------------------------------
[01:00:19] [01:00:19] ------------------------------------------
[01:00:19] stderr:
[01:00:19] ------------------------------------------
[01:00:19] error[E0185]: method `from` has a `&self` declaration in the impl, but not in the trait
[01:00:19] --> /checkout/src/test/ui/issue-48276.rs:21:5
[01:00:19] |
[01:00:19] LL | fn from(a: A) -> Self;
[01:00:19] | ---------------------- trait method declared without `&self`
[01:00:19] ...
[01:00:19] LL | fn from(self: &'a Self) -> &'b str {
[01:00:19] | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ `&self` used in impl
[01:00:19] [01:00:19] error[E0185]: method `from` has a `&self` declaration in the impl, but not in the trait
[01:00:19] --> /checkout/src/test/ui/issue-48276.rs:30:5
[01:00:19] |
[01:00:19] LL | fn from(&self) -> B {
[01:00:19] | ^^^^^^^^^^^^^^^^^^^ `&self` used in impl
[01:00:19] |
[01:00:19] = note: `from` from trait: `fn(T) -> Self`
[01:00:19] [01:00:19] error[E0185]: method `from` has a `&self` declaration in the impl, but not in the trait
[01:00:19] --> /checkout/src/test/ui/issue-48276.rs:37:5
[01:00:19] |
[01:00:19] LL | fn from(&self) -> &'static str {
[01:00:19] | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ `&self` used in impl
[01:00:19] |
[01:00:19] = note: `from` from trait: `fn(T) -> Self`
[01:00:19] [01:00:19] error: aborting due to 3 previous errors
[01:00:19] [01:00:19] If you want more information on this error, try using "rustc --explain E0185"
[01:00:19] [01:00:19] ------------------------------------------
[01:00:19] [01:00:19] thread '[ui] ui/issue-48276.rs' panicked at 'explicit panic', tools/compiletest/src/runtest.rs:2893:9
[01:00:19] note: Run with `RUST_BACKTRACE=1` for a backtrace.
[01:00:19] [01:00:19] [01:00:19] failures:
[01:00:19] [ui] ui/issue-48276.rs
[01:00:19] [01:00:19] test result: FAILED. 1243 passed; 1 failed; 4 ignored; 0 measured; 0 filtered out
[01:00:19] [01:00:19] thread 'main' panicked at 'Some tests failed', tools/compiletest/src/main.rs:476:22
[01:00:19] 

[emilyalbini]

That failure is caused by #48449, which replaces line numbers with LL.

[Manishearth]

@bors r-

re-r+ when this is fixed

[nikomatsakis]

easiest way to fix is to rebase and re-run the UI tests locally

[sapphire-arches]

Yep. I'll try and get to this tonight, and will certainly have it by later tomorrow. I've gotten unexpectedly busy this week.

…

On Thu, Mar 1, 2018, 13:28 Niko Matsakis ***@***.***> wrote: easiest way to fix is to rebase and re-run the UI tests locally — You are receiving this because you were mentioned. Reply to this email directly, view it on GitHub <#48419 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/ABcc_EDw7wFqKFFaNpf8Y5ys7qog7IZdks5taD3TgaJpZM4SOsQM> .

[sapphire-arches]

Rebased and updated to new stderr format. Should be an easy review =)

[nikomatsakis]

@bors r+

[bors]

📌 Commit c0d41fb has been approved by nikomatsakis

[bors]

⌛ Testing commit c0d41fb with merge 9a46d8adb83f73c72a2e876764993c4746957199...

[bors]

💔 Test failed - status-appveyor

[emilyalbini]

Appveyor timeout on dist x86_64.

@bors retry

[kennytm]

Note: Timeout is due to being stuck when cloning rust-by-examples. This happened 1 month before in #47761 (comment).

[bors]

⌛ Testing commit c0d41fb with merge 0bae326...

[bors]

☀️ Test successful - status-appveyor, status-travis
Approved by: nikomatsakis
Pushing 0bae326 to master...