rest_when_destructuring_struct: check if inside of proc macro

Author: Erk-

clippy_lints/src/rest_when_destructuring_struct.rs

@@ -1,5 +1,6 @@
 use crate::rustc_lint::LintContext as _;
 use clippy_utils::diagnostics::span_lint_and_then;
+use clippy_utils::is_from_proc_macro;
 use itertools::Itertools;
 use rustc_abi::VariantIdx;
 use rustc_lint::LateLintPass;
@@ -50,6 +51,10 @@ impl<'tcx> LateLintPass<'tcx> for RestWhenDestructuringStruct {
             return;
         }
 
+        if is_from_proc_macro(cx, pat) {
+            return;
+        }
+
         if let rustc_hir::PatKind::Struct(path, fields, true) = pat.kind {
             let qty = cx.typeck_results().qpath_res(&path, pat.hir_id);
             let ty = cx.typeck_results().pat_ty(pat);

tests/ui/rest_when_destructuring_struct.fixed

@@ -1,7 +1,10 @@
+//@aux-build:proc_macros.rs
 #![warn(clippy::rest_when_destructuring_struct)]
 #![allow(dead_code)]
 #![allow(unused_variables)]
 
+extern crate proc_macros;
+
 struct S {
     a: u8,
     b: u8,
@@ -20,6 +23,9 @@ fn main() {
     let S { a, b, c: _ } = s;
     //~^ rest_when_destructuring_struct
 
+    let S { a, b, c,  } = s;
+    //~^ rest_when_destructuring_struct
+
     let e = E::A { a1: 1, a2: 2 };
 
     match e {
@@ -36,4 +42,15 @@ fn main() {
         //~^ rest_when_destructuring_struct
         E::C {} => (),
     }
+
+    proc_macros::external! {
+        let s1 = S { a: 1, b: 2, c: 3 };
+        let S { a, b, .. } = s1;
+    }
+
+    proc_macros::with_span! {
+        span
+        let s2 = S { a: 1, b: 2, c: 3 };
+        let S { a, b, .. } = s2;
+    }
 }

tests/ui/rest_when_destructuring_struct.rs

@@ -1,7 +1,10 @@
+//@aux-build:proc_macros.rs
 #![warn(clippy::rest_when_destructuring_struct)]
 #![allow(dead_code)]
 #![allow(unused_variables)]
 
+extern crate proc_macros;
+
 struct S {
     a: u8,
     b: u8,
@@ -20,6 +23,9 @@ fn main() {
     let S { a, b, .. } = s;
     //~^ rest_when_destructuring_struct
 
+    let S { a, b, c, .. } = s;
+    //~^ rest_when_destructuring_struct
+
     let e = E::A { a1: 1, a2: 2 };
 
     match e {
@@ -36,4 +42,15 @@ fn main() {
         //~^ rest_when_destructuring_struct
         E::C {} => (),
     }
+
+    proc_macros::external! {
+        let s1 = S { a: 1, b: 2, c: 3 };
+        let S { a, b, .. } = s1;
+    }
+
+    proc_macros::with_span! {
+        span
+        let s2 = S { a: 1, b: 2, c: 3 };
+        let S { a, b, .. } = s2;
+    }
 }

tests/ui/rest_when_destructuring_struct.stderr

@@ -1,5 +1,5 @@
 error: struct destructuring with rest (..)
-  --> tests/ui/rest_when_destructuring_struct.rs:20:9
+  --> tests/ui/rest_when_destructuring_struct.rs:23:9
    |
 LL |     let S { a, b, .. } = s;
    |         ^^^^^^^^^^^^^^
@@ -13,7 +13,19 @@ LL +     let S { a, b, c: _ } = s;
    |
 
 error: struct destructuring with rest (..)
-  --> tests/ui/rest_when_destructuring_struct.rs:27:9
+  --> tests/ui/rest_when_destructuring_struct.rs:26:9
+   |
+LL |     let S { a, b, c, .. } = s;
+   |         ^^^^^^^^^^^^^^^^^
+   |
+help: consider explicitly ignoring remaining fields with wildcard patterns (x: _)
+   |
+LL -     let S { a, b, c, .. } = s;
+LL +     let S { a, b, c,  } = s;
+   |
+
+error: struct destructuring with rest (..)
+  --> tests/ui/rest_when_destructuring_struct.rs:33:9
    |
 LL |         E::B { .. } => (),
    |         ^^^^^^^^^^^
@@ -25,7 +37,7 @@ LL +         E::B { b1: _, b2: _ } => (),
    |
 
 error: struct destructuring with rest (..)
-  --> tests/ui/rest_when_destructuring_struct.rs:29:9
+  --> tests/ui/rest_when_destructuring_struct.rs:35:9
    |
 LL |         E::C { .. } => (),
    |         ^^^^^^^^^^^
@@ -37,7 +49,7 @@ LL +         E::C {  } => (),
    |
 
 error: struct destructuring with rest (..)
-  --> tests/ui/rest_when_destructuring_struct.rs:35:9
+  --> tests/ui/rest_when_destructuring_struct.rs:41:9
    |
 LL |         E::B { b1: _, .. } => (),
    |         ^^^^^^^^^^^^^^^^^^
@@ -48,5 +60,5 @@ LL -         E::B { b1: _, .. } => (),
 LL +         E::B { b1: _, b2: _ } => (),
    |
 
-error: aborting due to 4 previous errors
+error: aborting due to 5 previous errors