Allow more dead code

oli-obk · oli-obk · commit c85e4240be20 · 2025-08-26T07:19:59.000Z
diff --git a/test_suite/tests/regression/issue2371.rs b/test_suite/tests/regression/issue2371.rs
@@ -1,3 +1,5 @@
+#![allow(dead_code)]
+
 use serde_derive::Deserialize;
 
 #[derive(Deserialize)]
diff --git a/test_suite/tests/regression/issue2409.rs b/test_suite/tests/regression/issue2409.rs
@@ -1,3 +1,5 @@
+#![allow(dead_code)]
+
 use serde_derive::Deserialize;
 
 macro_rules! bug {
diff --git a/test_suite/tests/regression/issue2844.rs b/test_suite/tests/regression/issue2844.rs
@@ -1,4 +1,4 @@
-#![allow(clippy::trivially_copy_pass_by_ref)]
+#![allow(clippy::trivially_copy_pass_by_ref, dead_code)]
 
 use serde_derive::{Deserialize, Serialize};
 
diff --git a/test_suite/tests/regression/issue2846.rs b/test_suite/tests/regression/issue2846.rs
@@ -1,4 +1,4 @@
-#![allow(clippy::trivially_copy_pass_by_ref)]
+#![allow(clippy::trivially_copy_pass_by_ref, dead_code)]
 
 use serde_derive::Deserialize;
 
diff --git a/test_suite/tests/test_borrow.rs b/test_suite/tests/test_borrow.rs
@@ -1,7 +1,10 @@
 #![allow(
     clippy::derive_partial_eq_without_eq,
     clippy::items_after_statements,
-    clippy::used_underscore_binding
+    clippy::used_underscore_binding,
+    // We use lots of declarations inside function bodies to avoid conflicts,
+    // but they aren't used. We just want to make sure they compile.
+    dead_code,
 )]
 
 use serde::de::value::{BorrowedStrDeserializer, MapDeserializer};
diff --git a/test_suite/tests/test_gen.rs b/test_suite/tests/test_gen.rs
@@ -18,7 +18,10 @@
     clippy::ptr_arg,
     clippy::too_many_lines,
     clippy::trivially_copy_pass_by_ref,
-    clippy::type_repetition_in_bounds
+    clippy::type_repetition_in_bounds,
+    // We use lots of declarations inside function bodies to avoid conflicts,
+    // but they aren't used. We just want to make sure they compile.
+    dead_code,
 )]
 #![deny(clippy::collection_is_never_read)]
 
diff --git a/test_suite/tests/test_remote.rs b/test_suite/tests/test_remote.rs
@@ -1,4 +1,4 @@
-#![allow(clippy::redundant_field_names)]
+#![allow(clippy::redundant_field_names, dead_code)]
 
 use serde_derive::{Deserialize, Serialize};
 
diff --git a/test_suite/tests/test_self.rs b/test_suite/tests/test_self.rs
@@ -1,4 +1,4 @@
-#![allow(clippy::used_underscore_binding)]
+#![allow(clippy::used_underscore_binding, dead_code)]
 
 use serde_derive::{Deserialize, Serialize};
 
diff --git a/test_suite/tests/ui/conflict/alias-enum.stderr b/test_suite/tests/ui/conflict/alias-enum.stderr
@@ -7,18 +7,18 @@ error[E0425]: cannot find value `__FAIL__` in this scope
 warning: unreachable pattern
   --> tests/ui/conflict/alias-enum.rs:13:9
    |
-8  |         #[serde(alias = "a", alias = "b", alias = "c")]
+ 8 |         #[serde(alias = "a", alias = "b", alias = "c")]
    |                                      --- matches all the relevant values
 ...
 13 |         b: (),
    |         ^ no value can reach this
    |
-   = note: `#[warn(unreachable_patterns)]` on by default
+   = note: `#[warn(unreachable_patterns)]` (part of `#[warn(unused)]`) on by default
 
 warning: unreachable pattern
   --> tests/ui/conflict/alias-enum.rs:12:25
    |
-8  |         #[serde(alias = "a", alias = "b", alias = "c")]
+ 8 |         #[serde(alias = "a", alias = "b", alias = "c")]
    |                                                   --- matches all the relevant values
 ...
 12 |         #[serde(alias = "c")]
diff --git a/test_suite/tests/ui/conflict/alias.stderr b/test_suite/tests/ui/conflict/alias.stderr
@@ -7,13 +7,13 @@ error[E0425]: cannot find value `__FAIL__` in this scope
 warning: unreachable pattern
   --> tests/ui/conflict/alias.rs:10:5
    |
-5  |     #[serde(alias = "a", alias = "b", alias = "c")]
+ 5 |     #[serde(alias = "a", alias = "b", alias = "c")]
    |                                  --- matches all the relevant values
 ...
 10 |     b: (),
    |     ^ no value can reach this
    |
-   = note: `#[warn(unreachable_patterns)]` on by default
+   = note: `#[warn(unreachable_patterns)]` (part of `#[warn(unused)]`) on by default
 
 warning: unreachable pattern
  --> tests/ui/conflict/alias.rs:9:21
diff --git a/test_suite/tests/ui/conflict/internal-tag-alias.stderr b/test_suite/tests/ui/conflict/internal-tag-alias.stderr
@@ -1,11 +1,11 @@
 error: variant field name `conflict` conflicts with internal tag
   --> tests/ui/conflict/internal-tag-alias.rs:4:1
    |
-4  | / #[serde(tag = "conflict")]
-5  | | enum E {
-6  | |     A {
-7  | |         #[serde(alias = "conflict")]
-8  | |         x: (),
-9  | |     },
+ 4 | / #[serde(tag = "conflict")]
+ 5 | | enum E {
+ 6 | |     A {
+ 7 | |         #[serde(alias = "conflict")]
+ 8 | |         x: (),
+ 9 | |     },
 10 | | }
    | |_^
diff --git a/test_suite/tests/ui/conflict/internal-tag.stderr b/test_suite/tests/ui/conflict/internal-tag.stderr
@@ -1,11 +1,11 @@
 error: variant field name `conflict` conflicts with internal tag
   --> tests/ui/conflict/internal-tag.rs:4:1
    |
-4  | / #[serde(tag = "conflict")]
-5  | | enum E {
-6  | |     A {
-7  | |         #[serde(rename = "conflict")]
-8  | |         x: (),
-9  | |     },
+ 4 | / #[serde(tag = "conflict")]
+ 5 | | enum E {
+ 6 | |     A {
+ 7 | |         #[serde(rename = "conflict")]
+ 8 | |         x: (),
+ 9 | |     },
 10 | | }
    | |_^
diff --git a/test_suite/tests/ui/default-attribute/incorrect_type_enum_adjacently_tagged.stderr b/test_suite/tests/ui/default-attribute/incorrect_type_enum_adjacently_tagged.stderr
@@ -1,7 +1,7 @@
 error[E0308]: `match` arms have incompatible types
   --> tests/ui/default-attribute/incorrect_type_enum_adjacently_tagged.rs:10:33
    |
-5  | #[derive(Deserialize)]
+ 5 | #[derive(Deserialize)]
    |          -----------
    |          |
    |          this is found to be of type `i8`
@@ -13,7 +13,7 @@ error[E0308]: `match` arms have incompatible types
 error[E0308]: `match` arms have incompatible types
   --> tests/ui/default-attribute/incorrect_type_enum_adjacently_tagged.rs:12:27
    |
-5  | #[derive(Deserialize)]
+ 5 | #[derive(Deserialize)]
    |          -----------
    |          |
    |          this is found to be of type `u8`
@@ -25,7 +25,7 @@ error[E0308]: `match` arms have incompatible types
 error[E0308]: `match` arms have incompatible types
   --> tests/ui/default-attribute/incorrect_type_enum_adjacently_tagged.rs:15:27
    |
-5  | #[derive(Deserialize)]
+ 5 | #[derive(Deserialize)]
    |          -----------
    |          |
    |          this is found to be of type `i8`
diff --git a/test_suite/tests/ui/default-attribute/incorrect_type_enum_externally_tagged.stderr b/test_suite/tests/ui/default-attribute/incorrect_type_enum_externally_tagged.stderr
@@ -13,7 +13,7 @@ error[E0308]: `match` arms have incompatible types
 error[E0308]: `match` arms have incompatible types
   --> tests/ui/default-attribute/incorrect_type_enum_externally_tagged.rs:11:27
    |
-5  | #[derive(Deserialize)]
+ 5 | #[derive(Deserialize)]
    |          -----------
    |          |
    |          this is found to be of type `u8`
@@ -25,7 +25,7 @@ error[E0308]: `match` arms have incompatible types
 error[E0308]: `match` arms have incompatible types
   --> tests/ui/default-attribute/incorrect_type_enum_externally_tagged.rs:14:27
    |
-5  | #[derive(Deserialize)]
+ 5 | #[derive(Deserialize)]
    |          -----------
    |          |
    |          this is found to be of type `i8`
diff --git a/test_suite/tests/ui/default-attribute/incorrect_type_enum_internally_tagged.stderr b/test_suite/tests/ui/default-attribute/incorrect_type_enum_internally_tagged.stderr
@@ -1,7 +1,7 @@
 error[E0308]: `match` arms have incompatible types
   --> tests/ui/default-attribute/incorrect_type_enum_internally_tagged.rs:12:27
    |
-5  | #[derive(Deserialize)]
+ 5 | #[derive(Deserialize)]
    |          -----------
    |          |
    |          this is found to be of type `u8`
@@ -13,7 +13,7 @@ error[E0308]: `match` arms have incompatible types
 error[E0308]: `match` arms have incompatible types
   --> tests/ui/default-attribute/incorrect_type_enum_internally_tagged.rs:15:27
    |
-5  | #[derive(Deserialize)]
+ 5 | #[derive(Deserialize)]
    |          -----------
    |          |
    |          this is found to be of type `i8`
diff --git a/test_suite/tests/ui/default-attribute/incorrect_type_enum_untagged.stderr b/test_suite/tests/ui/default-attribute/incorrect_type_enum_untagged.stderr
@@ -1,7 +1,7 @@
 error[E0308]: `match` arms have incompatible types
   --> tests/ui/default-attribute/incorrect_type_enum_untagged.rs:10:33
    |
-5  | #[derive(Deserialize)]
+ 5 | #[derive(Deserialize)]
    |          -----------
    |          |
    |          this is found to be of type `i8`
@@ -13,7 +13,7 @@ error[E0308]: `match` arms have incompatible types
 error[E0308]: `match` arms have incompatible types
   --> tests/ui/default-attribute/incorrect_type_enum_untagged.rs:12:27
    |
-5  | #[derive(Deserialize)]
+ 5 | #[derive(Deserialize)]
    |          -----------
    |          |
    |          this is found to be of type `u8`
@@ -25,7 +25,7 @@ error[E0308]: `match` arms have incompatible types
 error[E0308]: `match` arms have incompatible types
   --> tests/ui/default-attribute/incorrect_type_enum_untagged.rs:15:27
    |
-5  | #[derive(Deserialize)]
+ 5 | #[derive(Deserialize)]
    |          -----------
    |          |
    |          this is found to be of type `i8`
diff --git a/test_suite/tests/ui/default-attribute/incorrect_type_newtype.stderr b/test_suite/tests/ui/default-attribute/incorrect_type_newtype.stderr
@@ -2,10 +2,7 @@ error[E0308]: mismatched types
  --> tests/ui/default-attribute/incorrect_type_newtype.rs:6:19
   |
 6 | #[serde(default = "main")]
-  |                   ^^^^^^
-  |                   |
-  |                   expected `Newtype`, found `()`
-  |                   expected due to this
+  |                   ^^^^^^ expected `Newtype`, found `()`
 
 error[E0308]: `match` arms have incompatible types
  --> tests/ui/default-attribute/incorrect_type_newtype.rs:7:34
diff --git a/test_suite/tests/ui/default-attribute/incorrect_type_struct.stderr b/test_suite/tests/ui/default-attribute/incorrect_type_struct.stderr
@@ -2,10 +2,7 @@ error[E0308]: mismatched types
  --> tests/ui/default-attribute/incorrect_type_struct.rs:6:19
   |
 6 | #[serde(default = "main")]
-  |                   ^^^^^^
-  |                   |
-  |                   expected `Struct`, found `()`
-  |                   expected due to this
+  |                   ^^^^^^ expected `Struct`, found `()`
 
 error[E0308]: `match` arms have incompatible types
  --> tests/ui/default-attribute/incorrect_type_struct.rs:8:23
@@ -22,7 +19,7 @@ error[E0308]: `match` arms have incompatible types
 error[E0308]: `match` arms have incompatible types
   --> tests/ui/default-attribute/incorrect_type_struct.rs:11:23
    |
-5  | #[derive(Deserialize)]
+ 5 | #[derive(Deserialize)]
    |          -----------
    |          |
    |          this is found to be of type `i8`
@@ -51,7 +48,7 @@ error[E0308]: mismatched types
 error[E0308]: mismatched types
   --> tests/ui/default-attribute/incorrect_type_struct.rs:11:23
    |
-5  | #[derive(Deserialize)]
+ 5 | #[derive(Deserialize)]
    |          ----------- expected due to the type of this binding
 ...
 11 |     #[serde(default = "main")]
diff --git a/test_suite/tests/ui/default-attribute/incorrect_type_tuple.stderr b/test_suite/tests/ui/default-attribute/incorrect_type_tuple.stderr
@@ -2,10 +2,7 @@ error[E0308]: mismatched types
  --> tests/ui/default-attribute/incorrect_type_tuple.rs:6:19
   |
 6 | #[serde(default = "main")]
-  |                   ^^^^^^
-  |                   |
-  |                   expected `Tuple`, found `()`
-  |                   expected due to this
+  |                   ^^^^^^ expected `Tuple`, found `()`
 
 error[E0308]: `match` arms have incompatible types
  --> tests/ui/default-attribute/incorrect_type_tuple.rs:7:36
diff --git a/test_suite/tests/ui/on_unimplemented.stderr b/test_suite/tests/ui/on_unimplemented.stderr
@@ -2,10 +2,15 @@ error[E0277]: the trait bound `MyStruct: Serialize` is not satisfied
   --> tests/ui/on_unimplemented.rs:21:15
    |
 21 |     to_string(&MyStruct);
-   |     --------- ^^^^^^^^^ the trait `Serialize` is not implemented for `MyStruct`
+   |     --------- ^^^^^^^^^ unsatisfied trait bound
    |     |
    |     required by a bound introduced by this call
    |
+help: the trait `Serialize` is not implemented for `MyStruct`
+  --> tests/ui/on_unimplemented.rs:18:1
+   |
+18 | struct MyStruct;
+   | ^^^^^^^^^^^^^^^
    = note: for local types consider adding `#[derive(serde::Serialize)]` to your `MyStruct` type
    = note: for types from other crates check whether the crate offers a `serde` feature flag
    = help: the following other types implement trait `Serialize`:
@@ -21,18 +26,23 @@ error[E0277]: the trait bound `MyStruct: Serialize` is not satisfied
 note: required by a bound in `to_string`
   --> tests/ui/on_unimplemented.rs:6:8
    |
-4  | fn to_string<T>(_: &T) -> String
+ 4 | fn to_string<T>(_: &T) -> String
    |    --------- required by a bound in this function
-5  | where
-6  |     T: Serialize,
+ 5 | where
+ 6 |     T: Serialize,
    |        ^^^^^^^^^ required by this bound in `to_string`
 
 error[E0277]: the trait bound `MyStruct: Deserialize<'_>` is not satisfied
   --> tests/ui/on_unimplemented.rs:22:23
    |
 22 |     let _: MyStruct = from_str("");
-   |                       ^^^^^^^^^^^^ the trait `Deserialize<'_>` is not implemented for `MyStruct`
+   |                       ^^^^^^^^^^^^ unsatisfied trait bound
+   |
+help: the trait `Deserialize<'_>` is not implemented for `MyStruct`
+  --> tests/ui/on_unimplemented.rs:18:1
    |
+18 | struct MyStruct;
+   | ^^^^^^^^^^^^^^^
    = note: for local types consider adding `#[derive(serde::Deserialize)]` to your `MyStruct` type
    = note: for types from other crates check whether the crate offers a `serde` feature flag
    = help: the following other types implement trait `Deserialize<'de>`:
diff --git a/test_suite/tests/ui/transparent/de_at_least_one.stderr b/test_suite/tests/ui/transparent/de_at_least_one.stderr
@@ -1,11 +1,11 @@
 error: #[serde(transparent)] requires at least one field that is neither skipped nor has a default
   --> tests/ui/transparent/de_at_least_one.rs:4:1
    |
-4  | / #[serde(transparent)]
-5  | | struct S {
-6  | |     #[serde(skip)]
-7  | |     a: u8,
-8  | |     #[serde(default)]
-9  | |     b: u8,
+ 4 | / #[serde(transparent)]
+ 5 | | struct S {
+ 6 | |     #[serde(skip)]
+ 7 | |     a: u8,
+ 8 | |     #[serde(default)]
+ 9 | |     b: u8,
 10 | | }
    | |_^
diff --git a/test_suite/tests/ui/with-variant/skip_de_struct_field.stderr b/test_suite/tests/ui/with-variant/skip_de_struct_field.stderr
@@ -1,10 +1,10 @@
 error: variant `Struct` cannot have both #[serde(deserialize_with)] and a field `f1` marked with #[serde(skip_deserializing)]
   --> tests/ui/with-variant/skip_de_struct_field.rs:5:5
    |
-5  | /     #[serde(deserialize_with = "deserialize_some_other_variant")]
-6  | |     Struct {
-7  | |         #[serde(skip_deserializing)]
-8  | |         f1: String,
-9  | |         f2: u8,
+ 5 | /     #[serde(deserialize_with = "deserialize_some_other_variant")]
+ 6 | |     Struct {
+ 7 | |         #[serde(skip_deserializing)]
+ 8 | |         f1: String,
+ 9 | |         f2: u8,
 10 | |     },
    | |_____^
diff --git a/test_suite/tests/ui/with-variant/skip_ser_struct_field.stderr b/test_suite/tests/ui/with-variant/skip_ser_struct_field.stderr
@@ -1,10 +1,10 @@
 error: variant `Struct` cannot have both #[serde(serialize_with)] and a field `f1` marked with #[serde(skip_serializing)]
   --> tests/ui/with-variant/skip_ser_struct_field.rs:5:5
    |
-5  | /     #[serde(serialize_with = "serialize_some_other_variant")]
-6  | |     Struct {
-7  | |         #[serde(skip_serializing)]
-8  | |         f1: String,
-9  | |         f2: u8,
+ 5 | /     #[serde(serialize_with = "serialize_some_other_variant")]
+ 6 | |     Struct {
+ 7 | |         #[serde(skip_serializing)]
+ 8 | |         f1: String,
+ 9 | |         f2: u8,
 10 | |     },
    | |_____^
diff --git a/test_suite/tests/ui/with-variant/skip_ser_struct_field_if.stderr b/test_suite/tests/ui/with-variant/skip_ser_struct_field_if.stderr
@@ -1,10 +1,10 @@
 error: variant `Struct` cannot have both #[serde(serialize_with)] and a field `f1` marked with #[serde(skip_serializing_if)]
   --> tests/ui/with-variant/skip_ser_struct_field_if.rs:5:5
    |
-5  | /     #[serde(serialize_with = "serialize_some_newtype_variant")]
-6  | |     Struct {
-7  | |         #[serde(skip_serializing_if = "always")]
-8  | |         f1: String,
-9  | |         f2: u8,
+ 5 | /     #[serde(serialize_with = "serialize_some_newtype_variant")]
+ 6 | |     Struct {
+ 7 | |         #[serde(skip_serializing_if = "always")]
+ 8 | |         f1: String,
+ 9 | |         f2: u8,
 10 | |     },
    | |_____^
diff --git a/test_suite/tests/ui/with/incorrect_type.stderr b/test_suite/tests/ui/with/incorrect_type.stderr

Original file line number	Diff line number	Diff line change
`@@ -1,3 +1,5 @@`
	`1`	`+#![allow(dead_code)]`
	`2`	`+`
`1`	`3`	`use serde_derive::Deserialize;`
`2`	`4`
`3`	`5`	`#[derive(Deserialize)]`
Original file line number	Diff line number	Diff line change
`@@ -1,4 +1,4 @@`
`1`		`-#![allow(clippy::trivially_copy_pass_by_ref)]`
	`1`	`+#![allow(clippy::trivially_copy_pass_by_ref, dead_code)]`
`2`	`2`
`3`	`3`	`use serde_derive::{Deserialize, Serialize};`
`4`	`4`
Original file line number	Diff line number	Diff line change
`@@ -1,4 +1,4 @@`
`1`		`-#![allow(clippy::redundant_field_names)]`
	`1`	`+#![allow(clippy::redundant_field_names, dead_code)]`
`2`	`2`
`3`	`3`	`use serde_derive::{Deserialize, Serialize};`
`4`	`4`
Original file line number	Diff line number	Diff line change
`@@ -1,4 +1,4 @@`
`1`		`-#![allow(clippy::used_underscore_binding)]`
	`1`	`+#![allow(clippy::used_underscore_binding, dead_code)]`
`2`	`2`
`3`	`3`	`use serde_derive::{Deserialize, Serialize};`
`4`	`4`