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, 22 insertions, 0 deletions

diff --git a/tests/ui/destructuring-assignment/note-unsupported.rs b/tests/ui/destructuring-assignment/note-unsupported.rs
new file mode 100644
index 00000000000..c69edd42170
--- /dev/null
+++ b/tests/ui/destructuring-assignment/note-unsupported.rs
@@ -0,0 +1,22 @@
+struct S { x: u8, y: u8 }
+
+fn main() {
+    let (a, b) = (1, 2);
+
+    (a, b) = (3, 4);
+    (a, b) += (3, 4); //~ ERROR invalid left-hand side of assignment
+    //~| ERROR binary assignment operation `+=` cannot be applied
+
+    [a, b] = [3, 4];
+    [a, b] += [3, 4]; //~ ERROR invalid left-hand side of assignment
+    //~| ERROR binary assignment operation `+=` cannot be applied
+
+    let s = S { x: 3, y: 4 };
+
+    S { x: a, y: b } = s;
+    S { x: a, y: b } += s; //~ ERROR invalid left-hand side of assignment
+    //~| ERROR binary assignment operation `+=` cannot be applied
+
+    S { x: a, ..s } = S { x: 3, y: 4 };
+    //~^ ERROR functional record updates are not allowed in destructuring assignments
+}