Changed error message E0408 to new format

[faebser]

Followed your text and was able to change the ouput to the new format.
I did not encounter any broken test therefore this is a really small commit.

Thanks for letting me hack on the compiler :)

r? @jonathandturner

[rust-highfive]

Thanks for the pull request, and welcome! The Rust team is excited to review your changes, and you should hear from @jonathandturner (or someone else) soon.

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[faebser]

Part of #35233
Fixes #35698

[GuillaumeGomez]

Thanks for your PR!

You also need to update the corresponding test(s) to reflect your changes. They are located in src/test/compile_fail/.

[sophiajt]

@faebser - as @GuillaumeGomez mentions, the test infrastructure has some quirks. One is that the labels aren't tested until you add your first NOTE. You can read about this in the Extra Credit part of the blog post

[faebser]

@jonathandturner thanks for the heads up. I will work on the test as soon I have time.

[GuillaumeGomez]

@faebser: Don't worry, we're not in a hurry. Just comment here once done.

[faebser]

@jonathandturner I don't really get where I have to add the note?
If i try to add a note to https://github.com/rust-lang/rust/blob/master/src/test/compile-fail/E0408.rs (which I think is the original test case that you refer to in your blog post) I just get an unexpected note error if i run the test.

[sophiajt]

@faebser - can you add your changes to this PR so we can take a look?

[faebser]

@jonathandturner I added my try as a commit to the PR.
Running python src/bootstrap/bootstrap.py --step check-cfail --stage 1 gives the following errors:

failures:
---- [compile-fail] compile-fail/E0408.rs stdout ----
error: /home/faebser/workspace/rust/src/test/compile-fail/E0408.rs:15:unexpected"error":'15:19:15:23: variable `y` from pattern #1 is not bound in pattern #2[E0408]'
error: /home/faebser/workspace/rust/src/test/compile-fail/E0408.rs:15:unexpected"note":'pattern doesn't bind `y`'
error: /home/faebser/workspace/rust/src/test/compile-fail/E0408.rs:14: expected error not found: variable `y` from pattern #2 is not bound in pattern #1
error: /home/faebser/workspace/rust/src/test/compile-fail/E0408.rs:14: expected note not found: pattern doesn't bind `y`
error:2 unexpected errors found,2 expected errors not found
status: exit code:101

[GuillaumeGomez]

Then fix them? I don't know what to add actually. :-/

[faebser]

@GuillaumeGomez: I am sorry but I am a bit lost and I don't really understand how to fix this error. I added them to this PR because @jonathandturner asked me to.

[GuillaumeGomez]

The "errors" you see come from src/test/compile-fail/E0408.rs. So, you added annotations (like `//~ ERROR E0408') but some of them aren't matched with the current rustc output (that you updated).

So let's see the first one:

E0408.rs:15: unexpected "error": '15:19: 15:23: variable `y` from pattern #1 is not bound in pattern #2 [E0408]'

It says that an annotation was not found. So let's look to your file:

//~^ ERROR variable `y` from pattern #2 is not bound in pattern #1

It means you expect an error to be thrown by the line before this one (the "^" says it). Better like this?

[faebser]

@GuillaumeGomez: thanks for your comment. I also realised that #1 and #2 were the wrong way around thus generating the error.
I added one more test and will try to find the remaining ones tomorrow.

[GuillaumeGomez]

Once these fixed, please squash your commits. If you don't know how to do it, take a look here.

[GuillaumeGomez]

Generally, we use "//|" and not "//^" when it's on the same line. I mean that the note is thrown by the same line than the error, so it's the "same" issue. With this way to write it, we have the feeling that it's two different errors.

Also, can you align "//^ NOTE pattern doesn't bind y" with "// ERROR variable y from pattern #1 is not bound in pattern #2" please?

[GuillaumeGomez]

Same as above.

[faebser]

@GuillaumeGomez can you please review the third test too? thanks

[GuillaumeGomez]

All good for me. Please squash your commits now.

[KiChjang]

This looks like it only requires squashing, what's blocking this for 2 weeks?

[GuillaumeGomez]

No clue. :-/

[faebser]

Sorry for the delay, I thought that the squash was okay but after having another look today I saw that it did not work. I am working on fixing it right now.

[faebser]

@GuillaumeGomez: squash is okay now

[GuillaumeGomez]

Thanks!

@bors: r+ rollup

[bors]

📌 Commit 595b754 has been approved by GuillaumeGomez

[bors]

⌛ Testing commit 595b754 with merge c80d21d...

[bors]

💔 Test failed - auto-linux-cross-opt

[arielb1]

@bors retry

[alexcrichton]

@bors: retry