Move some tests from rustc_expand to rustc_parse.

[nnethercote]

There are some test cases involving parse and tokenstream and mut_visit that are located in rustc_expand. Because it used to be the case that constructing a ParseSess required the involvement of rustc_expand. However, since #64197 merged (a long time ago) rust_expand no longer needs to be involved.

This commit moves the tests into rustc_parse. This is the optimal place for the parse tests. It's not ideal for the tokenstream and mut_visit tests -- they would be better in rustc_ast -- but they still rely on parsing, which is not available in rustc_ast. But rustc_parse is lower down in the crate graph and closer to rustc_ast than rust_expand, so it's still an improvement for them.

The exact renaming is as follows:

• rustc_expand/src/mut_visit/tests.rs -> rustc_parse/src/parser/mut_visit/tests.rs
• rustc_expand/src/tokenstream/tests.rs -> rustc_parse/src/parser/tokenstream/tests.rs
• rustc_expand/src/tests.rs + rustc_expand/src/parse/tests.rs -> compiler/rustc_parse/src/parser/tests.rs

The latter two test files are combined because there's no need for them to be separate, and having a rustc_parse::parser::parse module would be weird. This also means some pub(crate)s can be removed.

r? @compiler-errors

[rustbot]

These commits modify the Cargo.lock file. Unintentional changes to Cargo.lock can be introduced when switching branches and rebasing PRs.

If this was unintentional then you should revert the changes before this PR is merged.
Otherwise, you can ignore this comment.

[compiler-errors]

@bors r+ rollup

[bors]

📌 Commit 70cc333 has been approved by compiler-errors

It is now in the queue for this repository.

[bors]

☔ The latest upstream changes (presumably #124646) made this pull request unmergeable. Please resolve the merge conflicts.

[bors]

🔒 Merge conflict

This pull request and the master branch diverged in a way that cannot be automatically merged. Please rebase on top of the latest master branch, and let the reviewer approve again.

How do I rebase?

Assuming self is your fork and upstream is this repository, you can resolve the conflict following these steps:

1. git checkout mv-expand-tests (switch to your branch)
2. git fetch upstream master (retrieve the latest master)
3. git rebase upstream/master -p (rebase on top of it)
4. Follow the on-screen instruction to resolve conflicts (check git status if you got lost).
5. git push self mv-expand-tests --force-with-lease (update this PR)

You may also read Git Rebasing to Resolve Conflicts by Drew Blessing for a short tutorial.

Please avoid the "Resolve conflicts" button on GitHub. It uses git merge instead of git rebase which makes the PR commit history more difficult to read.

Sometimes step 4 will complete without asking for resolution. This is usually due to difference between how Cargo.lock conflict is handled during merge and rebase. This is normal, and you should still perform step 5 to update this PR.

Error message

Removing compiler/rustc_expand/src/parse/tests.rs
Auto-merging compiler/rustc_expand/src/lib.rs
CONFLICT (content): Merge conflict in compiler/rustc_expand/src/lib.rs
Auto-merging Cargo.lock
Automatic merge failed; fix conflicts and then commit the result.

[nnethercote]

I rebased.

@bors r=compiler-errors

[bors]

📌 Commit 2acbe9c has been approved by compiler-errors

It is now in the queue for this repository.

[bors]

⌛ Testing commit 2acbe9c with merge 96f1da8...

[bors]

☀️ Test successful - checks-actions
Approved by: compiler-errors
Pushing 96f1da8 to master...

[rust-timer]

Finished benchmarking commit (96f1da8): comparison URL.

Overall result: no relevant changes - no action needed

@rustbot label: -perf-regression

Instruction count

This benchmark run did not return any relevant results for this metric.

Max RSS (memory usage)

This benchmark run did not return any relevant results for this metric.

Cycles

This benchmark run did not return any relevant results for this metric.

Binary size

This benchmark run did not return any relevant results for this metric.

Bootstrap: 676.339s -> 675.971s (-0.05%)
Artifact size: 315.76 MiB -> 315.93 MiB (0.06%)