Derive forward attribute

concordium-std/CHANGELOG.md

@@ -4,7 +4,9 @@
 
 - Support adding attribute `#[concordium(repr(u))]` for enum types, where `u` is either `u8` or `u16`. Setting this changes the integer serialization used for the variant tags in derive macros such as  `Serial`, `Deserial`, `DeserialWithState` and `SchemaType`.
 - Support adding attribute `#[concordium(tag = n)]` for enum variants, where `n` is some unsigned integer literal. Setting this attribute on a variant overrides the tag used in derive macros such as `Serial`, `Deserial`, `DeserialWithState` and `SchemaType`. Note that setting `#[concordium(repr(u*))]` is required when using this attribute.
-
+- Support adding `#[concordium(forward = n)]`, for enum variants, where `n` is either an unsigned integer literal, `cis2_events`, `cis3_events`, `cis4_events` or an array of the same options.
+  Setting this attribute on a variant overrides the (de)serialization to flatten with the (de)serialization of the inner field when using derive macros such as `Serial`, `Deserial`, `DeserialWithState` and `SchemaType`.
+  Note that setting `#[concordium(repr(u*))]` is required when using this attribute.
 
 ## concordium-std 7.0.0 (2023-06-16)
 

concordium-std/tests/derive-deserial-with-state/fail-colliding-forward.rs

@@ -0,0 +1,29 @@
+//! Ensure `derive(DeserialWithState)` fails when 'forward' attributes are
+//! colliding.
+use concordium_std::*;
+
+#[derive(DeserialWithState)]
+#[concordium(state_parameter = "S", repr(u8))]
+enum Count<S> {
+    One {
+        field: StateSet<u32, S>,
+    },
+    #[concordium(forward = [5, 6])]
+    Two(Inner),
+
+    #[concordium(forward = 5)]
+    Three(Inner),
+}
+
+#[derive(Deserial)]
+#[concordium(repr(u8))]
+enum Inner {
+    #[concordium(tag = 5)]
+    Alpha {
+        balance: u32,
+    },
+    #[concordium(tag = 6)]
+    Beta(u16),
+}
+
+fn main() {}

concordium-std/tests/derive-deserial-with-state/fail-colliding-forward.stderr

@@ -0,0 +1,11 @@
+error: The tag of 'Three' collides with the tag of 'Two'.
+  --> tests/derive-deserial-with-state/fail-colliding-forward.rs:14:28
+   |
+14 |     #[concordium(forward = 5)]
+   |                            ^
+
+error: The tag of 'Two' collides with the tag of 'Three'.
+  --> tests/derive-deserial-with-state/fail-colliding-forward.rs:11:29
+   |
+11 |     #[concordium(forward = [5, 6])]
+   |                             ^

concordium-std/tests/derive-deserial-with-state/fail-colliding-tag-forward.rs

@@ -0,0 +1,29 @@
+//! Ensure `derive(DeserialWithState)` fails when 'forward' and 'tag' attributes
+//! are colliding.
+use concordium_std::*;
+
+#[derive(DeserialWithState)]
+#[concordium(state_parameter = "S", repr(u8))]
+enum Count<S> {
+    One {
+        field: StateSet<u32, S>,
+    },
+    #[concordium(forward = [5, 6])]
+    Two(Inner),
+
+    #[concordium(tag = 5)]
+    Three(Inner),
+}
+
+#[derive(Deserial)]
+#[concordium(repr(u8))]
+enum Inner {
+    #[concordium(tag = 5)]
+    Alpha {
+        balance: u32,
+    },
+    #[concordium(tag = 6)]
+    Beta(u16),
+}
+
+fn main() {}

concordium-std/tests/derive-deserial-with-state/fail-colliding-tag-forward.stderr

@@ -0,0 +1,11 @@
+error: The tag of 'Three' collides with the tag of 'Two'.
+  --> tests/derive-deserial-with-state/fail-colliding-tag-forward.rs:14:18
+   |
+14 |     #[concordium(tag = 5)]
+   |                  ^^^
+
+error: The tag of 'Two' collides with the tag of 'Three'.
+  --> tests/derive-deserial-with-state/fail-colliding-tag-forward.rs:11:29
+   |
+11 |     #[concordium(forward = [5, 6])]
+   |                             ^

concordium-std/tests/derive-deserial-with-state/fail-forward-collide-with-inferred.rs

@@ -0,0 +1,25 @@
+//! Ensure `derive(DeserialWithState)` fails when a 'forward' attribute collides
+//! with the default tag for another variant.
+use concordium_std::*;
+
+#[derive(DeserialWithState)]
+#[concordium(state_parameter = "S", repr(u8))]
+enum Count<S> {
+    One {
+        field: StateSet<u32, S>,
+    },
+    #[concordium(forward = [0, 6])]
+    Two(Inner),
+}
+
+#[derive(Deserial)]
+#[concordium(repr(u8))]
+enum Inner {
+    Alpha {
+        balance: u32,
+    },
+    #[concordium(tag = 6)]
+    Beta(u16),
+}
+
+fn main() {}

concordium-std/tests/derive-deserial-with-state/fail-forward-collide-with-inferred.stderr

@@ -0,0 +1,11 @@
+error: The tag of 'Two' collides with the tag of 'One'.
+  --> tests/derive-deserial-with-state/fail-forward-collide-with-inferred.rs:11:29
+   |
+11 |     #[concordium(forward = [0, 6])]
+   |                             ^
+
+error: The tag of 'One' collides with the tag of 'Two'.
+ --> tests/derive-deserial-with-state/fail-forward-collide-with-inferred.rs:8:5
+  |
+8 |     One {
+  |     ^^^

concordium-std/tests/derive-deserial-with-state/fail-forward-gt-repr.rs

@@ -0,0 +1,26 @@
+//! Ensure `derive(DeserialWithState)` fails when a 'forward' attribute is
+//! greater than what 'repr(u8)' can represent.
+use concordium_std::*;
+
+#[derive(DeserialWithState)]
+#[concordium(state_parameter = "S", repr(u8))]
+enum Count<S> {
+    One {
+        field: StateSet<u32, S>,
+    },
+    #[concordium(forward = [500, 6])]
+    Two(Inner),
+}
+
+#[derive(Deserial)]
+#[concordium(repr(u16))]
+enum Inner {
+    #[concordium(tag = 500)]
+    Alpha {
+        balance: u32,
+    },
+    #[concordium(tag = 6)]
+    Beta(u16),
+}
+
+fn main() {}

concordium-std/tests/derive-deserial-with-state/fail-forward-gt-repr.stderr

@@ -0,0 +1,5 @@
+error: 'forward' attribute tag value of 500 cannot be represented by the type u8 set in 'repr(u8)'
+  --> tests/derive-deserial-with-state/fail-forward-gt-repr.rs:11:29
+   |
+11 |     #[concordium(forward = [500, 6])]
+   |                             ^^^

concordium-std/tests/derive-deserial-with-state/fail-forward-without-repr.rs

@@ -0,0 +1,26 @@
+//! Ensure `derive(DeserialWithState)` fails when using 'forward' attribute
+//! without a 'repr' attribute.
+use concordium_std::*;
+
+#[derive(DeserialWithState)]
+#[concordium(state_parameter = "S")]
+enum Count<S> {
+    One {
+        field: StateSet<u32, S>,
+    },
+    #[concordium(forward = [5, 6])]
+    Two(Inner),
+}
+
+#[derive(Deserial)]
+#[concordium(repr(u8))]
+enum Inner {
+    #[concordium(tag = 5)]
+    Alpha {
+        balance: u32,
+    },
+    #[concordium(tag = 6)]
+    Beta(u16),
+}
+
+fn main() {}

concordium-std/tests/derive-deserial-with-state/fail-forward-without-repr.stderr

@@ -0,0 +1,7 @@
+error: 'repr(..)' attribute must be set on the type when using 'forward' attribute
+ --> tests/derive-deserial-with-state/fail-forward-without-repr.rs:5:10
+  |
+5 | #[derive(DeserialWithState)]
+  |          ^^^^^^^^^^^^^^^^^
+  |
+  = note: this error originates in the derive macro `DeserialWithState` (in Nightly builds, run with -Z macro-backtrace for more info)

concordium-std/tests/derive-deserial/fail-colliding-forward.rs

@@ -0,0 +1,28 @@
+//! Ensure `derive(Deserial)` fails when 'forward' attributes are colliding.
+use concordium_std::*;
+
+#[derive(Deserial)]
+#[concordium(repr(u8))]
+enum Count {
+    One {
+        field: u32,
+    },
+    #[concordium(forward = [5, 6])]
+    Two(Inner),
+
+    #[concordium(forward = 5)]
+    Three(Inner),
+}
+
+#[derive(Deserial)]
+#[concordium(repr(u8))]
+enum Inner {
+    #[concordium(tag = 5)]
+    Alpha {
+        balance: u32,
+    },
+    #[concordium(tag = 6)]
+    Beta(u16),
+}
+
+fn main() {}

concordium-std/tests/derive-deserial/fail-colliding-forward.stderr

@@ -0,0 +1,11 @@
+error: The tag of 'Three' collides with the tag of 'Two'.
+  --> tests/derive-deserial/fail-colliding-forward.rs:13:28
+   |
+13 |     #[concordium(forward = 5)]
+   |                            ^
+
+error: The tag of 'Two' collides with the tag of 'Three'.
+  --> tests/derive-deserial/fail-colliding-forward.rs:10:29
+   |
+10 |     #[concordium(forward = [5, 6])]
+   |                             ^

concordium-std/tests/derive-deserial/fail-colliding-tag-forward.rs

@@ -0,0 +1,29 @@
+//! Ensure `derive(Deserial)` fails when 'forward' and 'tag' attributes are
+//! colliding.
+use concordium_std::*;
+
+#[derive(Deserial)]
+#[concordium(repr(u8))]
+enum Count {
+    One {
+        field: u32,
+    },
+    #[concordium(forward = [5, 6])]
+    Two(Inner),
+
+    #[concordium(tag = 5)]
+    Three(Inner),
+}
+
+#[derive(Deserial)]
+#[concordium(repr(u8))]
+enum Inner {
+    #[concordium(tag = 5)]
+    Alpha {
+        balance: u32,
+    },
+    #[concordium(tag = 6)]
+    Beta(u16),
+}
+
+fn main() {}

concordium-std/tests/derive-deserial/fail-colliding-tag-forward.stderr

@@ -0,0 +1,11 @@
+error: The tag of 'Three' collides with the tag of 'Two'.
+  --> tests/derive-deserial/fail-colliding-tag-forward.rs:14:18
+   |
+14 |     #[concordium(tag = 5)]
+   |                  ^^^
+
+error: The tag of 'Two' collides with the tag of 'Three'.
+  --> tests/derive-deserial/fail-colliding-tag-forward.rs:11:29
+   |
+11 |     #[concordium(forward = [5, 6])]
+   |                             ^

concordium-std/tests/derive-deserial/fail-forward-collide-with-inferred.rs

@@ -0,0 +1,25 @@
+//! Ensure `derive(Deserial)` fails when a 'forward' attribute collides with the
+//! default tag for another variant.
+use concordium_std::*;
+
+#[derive(Deserial)]
+#[concordium(repr(u8))]
+enum Count {
+    One {
+        field: u32,
+    },
+    #[concordium(forward = [0, 6])]
+    Two(Inner),
+}
+
+#[derive(Deserial)]
+#[concordium(repr(u8))]
+enum Inner {
+    Alpha {
+        balance: u32,
+    },
+    #[concordium(tag = 6)]
+    Beta(u16),
+}
+
+fn main() {}

concordium-std/tests/derive-deserial/fail-forward-collide-with-inferred.stderr

@@ -0,0 +1,11 @@
+error: The tag of 'Two' collides with the tag of 'One'.
+  --> tests/derive-deserial/fail-forward-collide-with-inferred.rs:11:29
+   |
+11 |     #[concordium(forward = [0, 6])]
+   |                             ^
+
+error: The tag of 'One' collides with the tag of 'Two'.
+ --> tests/derive-deserial/fail-forward-collide-with-inferred.rs:8:5
+  |
+8 |     One {
+  |     ^^^

concordium-std/tests/derive-deserial/fail-forward-gt-repr.rs

@@ -0,0 +1,26 @@
+//! Ensure `derive(Deserial)` fails when a 'forward' attribute is greater than
+//! what 'repr(u8)' can represent.
+use concordium_std::*;
+
+#[derive(Deserial)]
+#[concordium(repr(u8))]
+enum Count {
+    One {
+        field: u32,
+    },
+    #[concordium(forward = [500, 6])]
+    Two(Inner),
+}
+
+#[derive(Deserial)]
+#[concordium(repr(u16))]
+enum Inner {
+    #[concordium(tag = 500)]
+    Alpha {
+        balance: u32,
+    },
+    #[concordium(tag = 6)]
+    Beta(u16),
+}
+
+fn main() {}

concordium-std/tests/derive-deserial/fail-forward-gt-repr.stderr

@@ -0,0 +1,5 @@
+error: 'forward' attribute tag value of 500 cannot be represented by the type u8 set in 'repr(u8)'
+  --> tests/derive-deserial/fail-forward-gt-repr.rs:11:29
+   |
+11 |     #[concordium(forward = [500, 6])]
+   |                             ^^^

concordium-std/tests/derive-deserial/fail-forward-without-repr.rs

@@ -0,0 +1,25 @@
+//! Ensure `derive(Deserial)` fails when using 'forward' attribute without a
+//! 'repr' attribute.
+use concordium_std::*;
+
+#[derive(Deserial)]
+enum Count {
+    One {
+        field: u32,
+    },
+    #[concordium(forward = [5, 6])]
+    Two(Inner),
+}
+
+#[derive(Deserial)]
+#[concordium(repr(u8))]
+enum Inner {
+    #[concordium(tag = 5)]
+    Alpha {
+        balance: u32,
+    },
+    #[concordium(tag = 6)]
+    Beta(u16),
+}
+
+fn main() {}

concordium-std/tests/derive-deserial/fail-forward-without-repr.stderr

@@ -0,0 +1,7 @@
+error: 'repr(..)' attribute must be set on the type when using 'forward' attribute
+ --> tests/derive-deserial/fail-forward-without-repr.rs:5:10
+  |
+5 | #[derive(Deserial)]
+  |          ^^^^^^^^
+  |
+  = note: this error originates in the derive macro `Deserial` (in Nightly builds, run with -Z macro-backtrace for more info)