Generate shortcut for Clone and Ord only when all generics are custom bound (#137)

* Generate shortcut for Clone and Ord only when all generics are custom bound

* Formatting fixed

* unicode-ident pinning for CI tests

* Addition version pinning in CI

* Updated UI test on nightly

* Updated ui test for zeroize-on-drop

Author: spirali

.github/workflows/test.yml

@@ -67,6 +67,9 @@ jobs:
           cargo update -p glob --precise 0.3.2
           cargo update -p proc-macro2 --precise 1.0.80
           cargo update -p quote --precise 1.0.35
+          cargo update -p unicode-ident --precise 1.0.22
+          cargo update -p ryu --precise 1.0.20
+          cargo update -p itoa --precise 1.0.15
       - name: Build
         run:
           cargo build --workspace ${{ matrix.features }}
@@ -130,6 +133,9 @@ jobs:
           cargo update -p pretty_assertions --precise 1.4.0
           cargo update -p proc-macro2 --precise 1.0.80
           cargo update -p quote --precise 1.0.35
+          cargo update -p unicode-ident --precise 1.0.22
+          cargo update -p ryu --precise 1.0.20
+          cargo update -p itoa --precise 1.0.15
       - name: Build
         run:
           cargo build --target thumbv6m-none-eabi ${{ matrix.features }} -p ensure-no-std

src/attr/item.rs

@@ -238,6 +238,15 @@ impl DeriveWhere {
 		})
 	}
 
+	/// Returns `true` if all [`Generic`] are
+	/// [`CustomBound`](Generic::CustomBound)
+	pub fn all_custom_bound(&self) -> bool {
+		self.generics.iter().all(|generic| match generic {
+			Generic::CustomBound(_) => true,
+			Generic::NoBound(_) => false,
+		})
+	}
+
 	/// Returns `true` if the given generic type parameter if present.
 	pub fn has_type_param(&self, type_param: &Ident) -> bool {
 		self.generics.iter().any(|generic| match generic {

src/trait_/clone.rs

@@ -57,9 +57,7 @@ impl TraitImpl for Clone {
 		body: &TokenStream,
 	) -> TokenStream {
 		// Special implementation for items also implementing `Copy`.
-		if (derive_where.generics.is_empty() || derive_where.any_custom_bound())
-			&& derive_where.contains(Trait::Copy)
-		{
+		if (derive_where.all_custom_bound()) && derive_where.contains(Trait::Copy) {
 			return quote! {
 				#[inline]
 				fn clone(&self) -> Self { *self }
@@ -93,9 +91,7 @@ impl TraitImpl for Clone {
 	}
 
 	fn build_body(&self, derive_where: &DeriveWhere, data: &Data) -> TokenStream {
-		if (derive_where.generics.is_empty() || derive_where.any_custom_bound())
-			&& derive_where.contains(Trait::Copy)
-		{
+		if (derive_where.all_custom_bound()) && derive_where.contains(Trait::Copy) {
 			return TokenStream::new();
 		}
 

src/trait_/partial_ord.rs

@@ -33,9 +33,7 @@ impl TraitImpl for PartialOrd {
 		generics: &SplitGenerics<'_>,
 		body: &TokenStream,
 	) -> TokenStream {
-		let body = if (derive_where.generics.is_empty() || derive_where.any_custom_bound())
-			&& derive_where.contains(Trait::Ord)
-		{
+		let body = if (derive_where.all_custom_bound()) && derive_where.contains(Trait::Ord) {
 			quote! {
 				::core::option::Option::Some(::core::cmp::Ord::cmp(self, __other))
 			}
@@ -54,8 +52,7 @@ impl TraitImpl for PartialOrd {
 	fn build_body(&self, derive_where: &DeriveWhere, data: &Data) -> TokenStream {
 		if data.is_empty(**self)
 			|| data.is_incomparable()
-			|| ((derive_where.generics.is_empty() || derive_where.any_custom_bound())
-				&& derive_where.contains(Trait::Ord))
+			|| (derive_where.all_custom_bound() && derive_where.contains(Trait::Ord))
 		{
 			TokenStream::new()
 		} else {

tests/bound.rs

@@ -81,3 +81,17 @@ fn ord_requirement() {
 	#[derive_where(Eq, Ord, PartialEq, PartialOrd; T::Type)]
 	struct Test<T: Trait>(T::Type);
 }
+
+#[test]
+fn ord_and_partial_ord() {
+	trait Trait {}
+	#[derive_where(PartialOrd, Ord, PartialEq, Eq; I: Trait, T)]
+	struct Foo<T, I>(T, PhantomData<I>);
+}
+
+#[test]
+fn copy_and_clone() {
+	trait Trait {}
+	#[derive_where(Copy, Clone; I: Trait, T)]
+	struct Foo<T, I>(T, PhantomData<I>);
+}

tests/ui/union.stderr

@@ -6,11 +6,11 @@ error: traits other then `Clone` and `Copy` aren't supported by unions
 8 | | }
   | |_^
 
-error[E0277]: the trait bound `MissingCopy<T>: std::marker::Copy` is not satisfied
+error[E0277]: the trait bound `MissingCopy<T>: Copy` is not satisfied
   --> tests/ui/union.rs:10:1
    |
 10 | #[derive_where(Clone)]
-   | ^^^^^^^^^^^^^^^^^^^^^^ the trait `std::marker::Copy` is not implemented for `MissingCopy<T>`
+   | ^^^^^^^^^^^^^^^^^^^^^^ the trait `Copy` is not implemented for `MissingCopy<T>`
    |
 note: required by a bound in `__AssertCopy`
   --> tests/ui/union.rs:10:1

tests/ui/zeroize-on-drop/zeroize-on-drop.stderr

@@ -16,10 +16,11 @@ note: the following trait bounds were not satisfied:
   --> tests/ui/zeroize-on-drop/zeroize-on-drop.rs:10:1
    |
 10 | #[derive_where(ZeroizeOnDrop(no_drop))]
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ unsatisfied trait bound introduced in this `derive` macro
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ type parameter would need to implement `AssertZeroizeOnDrop`
+   = help: consider manually implementing the trait to avoid undesired bounds
    = help: items from traits can only be used if the type parameter is bounded by the trait
-   = note: this error originates in the derive macro `::derive_where::DeriveWhere` which comes from the expansion of the attribute macro `derive_where` (in Nightly builds, run with -Z macro-backtrace for more info)
+   = note: this error originates in the derive macro `::derive_where::DeriveWhere` (in Nightly builds, run with -Z macro-backtrace for more info)
 help: the following trait defines an item `__derive_where_zeroize_on_drop`, perhaps you need to restrict type parameter `T` with it:
    |
-11 | struct NoDropNoZeroizeOnDrop<T: <NoDropNoZeroizeOnDrop<T> as DeriveWhereAssertZeroizeOnDrop>::assert::AssertZeroizeOnDrop>(T);
-   |                               +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
+11 | struct NoDropNoZeroizeOnDrop<T: AssertZeroizeOnDrop>(T);
+   |                               +++++++++++++++++++++