Auto merge of #8500 - rust-lang:testless-dbg-macro, r=Manishearth

Omit dbg_macro in test code

This fixes #8481.

---

changelog: none

clippy_lints/src/dbg_macro.rs

@@ -1,4 +1,5 @@
 use clippy_utils::diagnostics::span_lint_and_sugg;
+use clippy_utils::is_in_test_function;
 use clippy_utils::macros::root_macro_call_first_node;
 use clippy_utils::source::snippet_with_applicability;
 use rustc_errors::Applicability;
@@ -35,6 +36,10 @@ impl LateLintPass<'_> for DbgMacro {
     fn check_expr(&mut self, cx: &LateContext<'_>, expr: &Expr<'_>) {
         let Some(macro_call) = root_macro_call_first_node(cx, expr) else { return };
         if cx.tcx.is_diagnostic_item(sym::dbg_macro, macro_call.def_id) {
+            // we make an exception for test code
+            if is_in_test_function(cx.tcx, expr.hir_id) {
+                return;
+            }
             let mut applicability = Applicability::MachineApplicable;
             let suggestion = match expr.peel_drop_temps().kind {
                 // dbg!()

tests/ui/dbg_macro.rs

@@ -1,3 +1,4 @@
+// compile-flags: --test
 #![warn(clippy::dbg_macro)]
 
 fn foo(n: u32) -> u32 {
@@ -40,3 +41,8 @@ mod issue7274 {
         dbg!(2);
     });
 }
+
+#[test]
+pub fn issue8481() {
+    dbg!(1);
+}

tests/ui/dbg_macro.stderr

@@ -1,5 +1,5 @@
 error: `dbg!` macro is intended as a debugging tool
-  --> $DIR/dbg_macro.rs:4:22
+  --> $DIR/dbg_macro.rs:5:22
    |
 LL |     if let Some(n) = dbg!(n.checked_sub(4)) { n } else { n }
    |                      ^^^^^^^^^^^^^^^^^^^^^^
@@ -11,7 +11,7 @@ LL |     if let Some(n) = n.checked_sub(4) { n } else { n }
    |                      ~~~~~~~~~~~~~~~~
 
 error: `dbg!` macro is intended as a debugging tool
-  --> $DIR/dbg_macro.rs:8:8
+  --> $DIR/dbg_macro.rs:9:8
    |
 LL |     if dbg!(n <= 1) {
    |        ^^^^^^^^^^^^
@@ -22,7 +22,7 @@ LL |     if n <= 1 {
    |        ~~~~~~
 
 error: `dbg!` macro is intended as a debugging tool
-  --> $DIR/dbg_macro.rs:9:9
+  --> $DIR/dbg_macro.rs:10:9
    |
 LL |         dbg!(1)
    |         ^^^^^^^
@@ -33,7 +33,7 @@ LL |         1
    |
 
 error: `dbg!` macro is intended as a debugging tool
-  --> $DIR/dbg_macro.rs:11:9
+  --> $DIR/dbg_macro.rs:12:9
    |
 LL |         dbg!(n * factorial(n - 1))
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^
@@ -44,7 +44,7 @@ LL |         n * factorial(n - 1)
    |
 
 error: `dbg!` macro is intended as a debugging tool
-  --> $DIR/dbg_macro.rs:16:5
+  --> $DIR/dbg_macro.rs:17:5
    |
 LL |     dbg!(42);
    |     ^^^^^^^^
@@ -55,7 +55,7 @@ LL |     42;
    |     ~~
 
 error: `dbg!` macro is intended as a debugging tool
-  --> $DIR/dbg_macro.rs:17:5
+  --> $DIR/dbg_macro.rs:18:5
    |
 LL |     dbg!(dbg!(dbg!(42)));
    |     ^^^^^^^^^^^^^^^^^^^^
@@ -66,7 +66,7 @@ LL |     dbg!(dbg!(42));
    |     ~~~~~~~~~~~~~~
 
 error: `dbg!` macro is intended as a debugging tool
-  --> $DIR/dbg_macro.rs:18:14
+  --> $DIR/dbg_macro.rs:19:14
    |
 LL |     foo(3) + dbg!(factorial(4));
    |              ^^^^^^^^^^^^^^^^^^
@@ -77,7 +77,7 @@ LL |     foo(3) + factorial(4);
    |              ~~~~~~~~~~~~
 
 error: `dbg!` macro is intended as a debugging tool
-  --> $DIR/dbg_macro.rs:19:5
+  --> $DIR/dbg_macro.rs:20:5
    |
 LL |     dbg!(1, 2, dbg!(3, 4));
    |     ^^^^^^^^^^^^^^^^^^^^^^
@@ -88,7 +88,7 @@ LL |     (1, 2, dbg!(3, 4));
    |     ~~~~~~~~~~~~~~~~~~
 
 error: `dbg!` macro is intended as a debugging tool
-  --> $DIR/dbg_macro.rs:20:5
+  --> $DIR/dbg_macro.rs:21:5
    |
 LL |     dbg!(1, 2, 3, 4, 5);
    |     ^^^^^^^^^^^^^^^^^^^
@@ -99,7 +99,7 @@ LL |     (1, 2, 3, 4, 5);
    |     ~~~~~~~~~~~~~~~
 
 error: `dbg!` macro is intended as a debugging tool
-  --> $DIR/dbg_macro.rs:40:9
+  --> $DIR/dbg_macro.rs:41:9
    |
 LL |         dbg!(2);
    |         ^^^^^^^