Auto merge of #106458 - albertlarsan68:move-tests, r=jyn514

Move src/test to the root

See MCP at rust-lang/compiler-team#573

There may be more changes needed.

The first commit is just the move of the files:
You can check that the first commit did not do anything else than renames by running
```
git diff --diff-filter=r -M100% <rust-lang remote>/master <first commit hash>
```
The output should be empty, because the filter excludes renames, and the match threshold for qualifying a rename is 100%.

The second one is mostly a "find and replace" of `src/test` to `tests` and whatever is needed to make CI pass.

What is left to do:
---

- [x] Move directory
- [ ] Change references to `src/test`
    - [x] Change references in-tree
    - [ ] Change references in submodules / out-of-tree docs
- [x] Make CI pass:
    - [x] Fix tidy
    - [x] Fix tests
    - [x] Bless tests if needed (shouldn't normally)
- [ ] Merge it !

1 files changed, 29 insertions, 0 deletions

diff --git a/tests/rustdoc/synthetic_auto/self-referential.rs b/tests/rustdoc/synthetic_auto/self-referential.rs
new file mode 100644
index 00000000000..c6ae96de776
--- /dev/null
+++ b/tests/rustdoc/synthetic_auto/self-referential.rs
@@ -0,0 +1,29 @@
+// Some unusual code minimized from
+// https://github.com/sile/handy_async/tree/7b619b762c06544fc67792c8ff8ebc24a88fdb98
+
+pub trait Pattern {
+    type Value;
+}
+
+pub struct Constrain<A, B = A, C = A>(A, B, C);
+
+impl<A, B, C> Pattern for Constrain<A, B, C>
+    where A: Pattern,
+          B: Pattern<Value = A::Value>,
+          C: Pattern<Value = A::Value>,
+{
+    type Value = A::Value;
+}
+
+pub struct Wrapper<T>(T);
+
+impl<T> Pattern for Wrapper<T> {
+    type Value = T;
+}
+
+
+// @has self_referential/struct.WriteAndThen.html
+// @has - '//*[@id="synthetic-implementations-list"]//*[@class="impl has-srclink"]//h3[@class="code-header"]' \
+// "impl<P1> Send for WriteAndThen<P1>where    <P1 as Pattern>::Value: Send"
+pub struct WriteAndThen<P1>(pub P1::Value,pub <Constrain<P1, Wrapper<P1::Value>> as Pattern>::Value)
+    where P1: Pattern;