Support opt-out of extra derived traits for rejections for #[derive(FromRequest)] (#729)

* Handle structs without fields

* Support opt-out of derived rejection traits

* Handle duplicate opt outs

* Improve error if opting out of `Display` or `Debug` but not `Error`

* document `rejection_derive`

* Handle using both `via` and `rejection_derive`

* don't derive debug for `RejectionDeriveOptOuts`

* Update axum-macros/src/from_request.rs

Co-authored-by: Jonas Platte <[email protected]>

Co-authored-by: Jonas Platte <[email protected]>

axum-macros/tests/from_request/fail/derive_opt_out_debug_and_display_without_error.rs

@@ -0,0 +1,9 @@
+use axum_macros::FromRequest;
+
+#[derive(FromRequest)]
+#[from_request(rejection_derive(!Debug, !Display))]
+struct Extractor {
+    body: String,
+}
+
+fn main() {}

axum-macros/tests/from_request/fail/derive_opt_out_debug_and_display_without_error.stderr

@@ -0,0 +1,5 @@
+error: opt out of `Debug` and `Display` requires also opting out of `Error`. Use `#[from_request(rejection_derive(!Debug, !Display, !Error))]`
+ --> tests/from_request/fail/derive_opt_out_debug_and_display_without_error.rs:4:34
+  |
+4 | #[from_request(rejection_derive(!Debug, !Display))]
+  |                                  ^^^^^

axum-macros/tests/from_request/fail/derive_opt_out_debug_without_error.rs

@@ -0,0 +1,9 @@
+use axum_macros::FromRequest;
+
+#[derive(FromRequest)]
+#[from_request(rejection_derive(!Debug))]
+struct Extractor {
+    body: String,
+}
+
+fn main() {}

axum-macros/tests/from_request/fail/derive_opt_out_debug_without_error.stderr

@@ -0,0 +1,5 @@
+error: opt out of `Debug` requires also opting out of `Error`. Use `#[from_request(rejection_derive(!Debug, !Error))]`
+ --> tests/from_request/fail/derive_opt_out_debug_without_error.rs:4:34
+  |
+4 | #[from_request(rejection_derive(!Debug))]
+  |                                  ^^^^^

axum-macros/tests/from_request/fail/derive_opt_out_display_without_error.rs

@@ -0,0 +1,9 @@
+use axum_macros::FromRequest;
+
+#[derive(FromRequest)]
+#[from_request(rejection_derive(!Display))]
+struct Extractor {
+    body: String,
+}
+
+fn main() {}

axum-macros/tests/from_request/fail/derive_opt_out_display_without_error.stderr

@@ -0,0 +1,5 @@
+error: opt out of `Display` requires also opting out of `Error`. Use `#[from_request(rejection_derive(!Display, !Error))]`
+ --> tests/from_request/fail/derive_opt_out_display_without_error.rs:4:34
+  |
+4 | #[from_request(rejection_derive(!Display))]
+  |                                  ^^^^^^^

axum-macros/tests/from_request/fail/derive_opt_out_duplicate.rs

@@ -0,0 +1,9 @@
+use axum_macros::FromRequest;
+
+#[derive(FromRequest)]
+#[from_request(rejection_derive(!Error, !Error))]
+struct Extractor {
+    body: String,
+}
+
+fn main() {}

axum-macros/tests/from_request/fail/derive_opt_out_duplicate.stderr

@@ -0,0 +1,5 @@
+error: `Error` opt out specified more than once
+ --> tests/from_request/fail/derive_opt_out_duplicate.rs:4:42
+  |
+4 | #[from_request(rejection_derive(!Error, !Error))]
+  |                                          ^^^^^

axum-macros/tests/from_request/fail/rejection_derive_and_via.rs

@@ -0,0 +1,10 @@
+use axum_macros::FromRequest;
+use axum::extract::Extension;
+
+#[derive(FromRequest, Clone)]
+#[from_request(rejection_derive(!Error), via(Extension))]
+struct Extractor {
+    config: String,
+}
+
+fn main() {}

axum-macros/tests/from_request/fail/rejection_derive_and_via.stderr

@@ -0,0 +1,13 @@
+error: cannot use both `rejection_derive` and `via`
+ --> tests/from_request/fail/rejection_derive_and_via.rs:5:42
+  |
+5 | #[from_request(rejection_derive(!Error), via(Extension))]
+  |                                          ^^^
+
+warning: unused import: `axum::extract::Extension`
+ --> tests/from_request/fail/rejection_derive_and_via.rs:2:5
+  |
+2 | use axum::extract::Extension;
+  |     ^^^^^^^^^^^^^^^^^^^^^^^^
+  |
+  = note: `#[warn(unused_imports)]` on by default

axum-macros/tests/from_request/fail/unknown_attr_container.rs

@@ -0,0 +1,7 @@
+use axum_macros::FromRequest;
+
+#[derive(FromRequest)]
+#[from_request(foo)]
+struct Extractor;
+
+fn main() {}

axum-macros/tests/from_request/fail/unknown_attr_container.stderr

@@ -0,0 +1,5 @@
+error: expected `via` or `rejection_derive`
+ --> tests/from_request/fail/unknown_attr_container.rs:4:16
+  |
+4 | #[from_request(foo)]
+  |                ^^^

axum-macros/tests/from_request/fail/unknown_attr_field.stderr

@@ -1,5 +1,5 @@
 error: expected `via`
- --> tests/from_request/fail/unknown_attr.rs:4:33
+ --> tests/from_request/fail/unknown_attr_field.rs:4:33
   |
 4 | struct Extractor(#[from_request(foo)] String);
   |                                 ^^^

axum-macros/tests/from_request/fail/via_and_rejection_derive.rs

@@ -0,0 +1,10 @@
+use axum_macros::FromRequest;
+use axum::extract::Extension;
+
+#[derive(FromRequest, Clone)]
+#[from_request(via(Extension), rejection_derive(!Error))]
+struct Extractor {
+    config: String,
+}
+
+fn main() {}

axum-macros/tests/from_request/fail/via_and_rejection_derive.stderr

@@ -0,0 +1,13 @@
+error: cannot use both `via` and `rejection_derive`
+ --> tests/from_request/fail/via_and_rejection_derive.rs:5:32
+  |
+5 | #[from_request(via(Extension), rejection_derive(!Error))]
+  |                                ^^^^^^^^^^^^^^^^
+
+warning: unused import: `axum::extract::Extension`
+ --> tests/from_request/fail/via_and_rejection_derive.rs:2:5
+  |
+2 | use axum::extract::Extension;
+  |     ^^^^^^^^^^^^^^^^^^^^^^^^
+  |
+  = note: `#[warn(unused_imports)]` on by default