Add a regression test for issue-82865

Author: JohnTitor

src/test/ui/resolve/issue-82865.rs

@@ -0,0 +1,13 @@
+// Regression test for #82865.
+
+#![feature(decl_macro)]
+
+use x::y::z; //~ ERROR: failed to resolve: maybe a missing crate `x`?
+
+macro mac () {
+    Box::z //~ ERROR: no function or associated item
+}
+
+fn main() {
+    mac!();
+}

src/test/ui/resolve/issue-82865.stderr

@@ -0,0 +1,21 @@
+error[E0433]: failed to resolve: maybe a missing crate `x`?
+  --> $DIR/issue-82865.rs:5:5
+   |
+LL | use x::y::z;
+   |     ^ maybe a missing crate `x`?
+
+error[E0599]: no function or associated item named `z` found for struct `Box<_, _>` in the current scope
+  --> $DIR/issue-82865.rs:8:10
+   |
+LL |     Box::z
+   |          ^ function or associated item not found in `Box<_, _>`
+...
+LL |     mac!();
+   |     ------- in this macro invocation
+   |
+   = note: this error originates in a macro (in Nightly builds, run with -Z macro-backtrace for more info)
+
+error: aborting due to 2 previous errors
+
+Some errors have detailed explanations: E0433, E0599.
+For more information about an error, try `rustc --explain E0433`.