[`use_self`] fix FP when trait impl defined in macro

Found when working on `lintcheck --fix`

3 files changed, 53 insertions, 0 deletions

diff --git a/clippy_lints/src/use_self.rs b/clippy_lints/src/use_self.rs
index 65f1b546208..acf27c34e94 100644
--- a/clippy_lints/src/use_self.rs
+++ b/clippy_lints/src/use_self.rs
@@ -103,6 +103,7 @@ impl<'tcx> LateLintPass<'tcx> for UseSelf {
             if parameters.as_ref().map_or(true, |params| {
                 !params.parenthesized && !params.args.iter().any(|arg| matches!(arg, GenericArg::Lifetime(_)))
             });
+            if !item.span.from_expansion();
             if !is_from_proc_macro(cx, item); // expensive, should be last check
             then {
                 StackItem::Check {
diff --git a/tests/ui/use_self_trait.fixed b/tests/ui/use_self_trait.fixed
index 9bcd692fb35..12adf1e41a6 100644
--- a/tests/ui/use_self_trait.fixed
+++ b/tests/ui/use_self_trait.fixed
@@ -112,4 +112,30 @@ impl NameTrait for u8 {
     }
 }
 
+mod impl_in_macro {
+    macro_rules! parse_ip_impl {
+        // minimized from serde=1.0.118
+        ($ty:ty) => {
+            impl FooTrait for $ty {
+                fn new() -> Self {
+                    <$ty>::bar()
+                }
+            }
+        };
+    }
+
+    struct Foo;
+
+    trait FooTrait {
+        fn new() -> Self;
+    }
+
+    impl Foo {
+        fn bar() -> Self {
+            Self
+        }
+    }
+    parse_ip_impl!(Foo); // Should not lint
+}
+
 fn main() {}
diff --git a/tests/ui/use_self_trait.rs b/tests/ui/use_self_trait.rs
index de305d40f33..49dbcddc1d8 100644
--- a/tests/ui/use_self_trait.rs
+++ b/tests/ui/use_self_trait.rs
@@ -112,4 +112,30 @@ impl NameTrait for u8 {
     }
 }
 
+mod impl_in_macro {
+    macro_rules! parse_ip_impl {
+        // minimized from serde=1.0.118
+        ($ty:ty) => {
+            impl FooTrait for $ty {
+                fn new() -> Self {
+                    <$ty>::bar()
+                }
+            }
+        };
+    }
+
+    struct Foo;
+
+    trait FooTrait {
+        fn new() -> Self;
+    }
+
+    impl Foo {
+        fn bar() -> Self {
+            Self
+        }
+    }
+    parse_ip_impl!(Foo); // Should not lint
+}
+
 fn main() {}