Enables where clauses for traits.

With these changes where clauses are enabled for traits. This commit also adds error handling when an `impl` is created for a generic trait with where clause. Generic traits are not supported yet on super traits or where clauses, when the support is added we should also perform the bounds check there. Fixes #4560 Fixes #970
FuelLabs · May 24, 2023 · 4f18e94 · 4f18e94
1 parent e5d3185
commit 4f18e94
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Showing 20 changed files with 175 additions and 24 deletions.
diff --git a/sway-core/src/semantic_analysis/ast_node/declaration/enum.rs b/sway-core/src/semantic_analysis/ast_node/declaration/enum.rs
@@ -27,7 +27,7 @@ impl ty::TyEnumDecl {
         // Type check the type parameters. This will also insert them into the
         // current namespace.
         let new_type_parameters = check!(
-            TypeParameter::type_check_type_params(ctx.by_ref(), type_parameters, false),
+            TypeParameter::type_check_type_params(ctx.by_ref(), type_parameters),
             return err(warnings, errors),
             warnings,
             errors

diff --git a/sway-core/src/semantic_analysis/ast_node/declaration/function.rs b/sway-core/src/semantic_analysis/ast_node/declaration/function.rs
@@ -68,7 +68,7 @@ impl ty::TyFunctionDecl {
         // Type check the type parameters. This will also insert them into the
         // current namespace.
         let new_type_parameters = check!(
-            TypeParameter::type_check_type_params(ctx.by_ref(), type_parameters, false),
+            TypeParameter::type_check_type_params(ctx.by_ref(), type_parameters),
             return err(warnings, errors),
             warnings,
             errors
@@ -149,7 +149,7 @@ impl ty::TyFunctionDecl {
         check!(
             return_type
                 .type_id
-                .check_type_parameter_bounds(&ctx, &return_type.span),
+                .check_type_parameter_bounds(&ctx, &return_type.span, vec![]),
             return err(warnings, errors),
             warnings,
             errors

diff --git a/sway-core/src/semantic_analysis/ast_node/declaration/function/function_parameter.rs b/sway-core/src/semantic_analysis/ast_node/declaration/function/function_parameter.rs
@@ -43,7 +43,7 @@ impl ty::TyFunctionParameter {
         check!(
             type_argument
                 .type_id
-                .check_type_parameter_bounds(&ctx, &type_argument.span),
+                .check_type_parameter_bounds(&ctx, &type_argument.span, vec![]),
             return err(warnings, errors),
             warnings,
             errors

diff --git a/sway-core/src/semantic_analysis/ast_node/declaration/impl_trait.rs b/sway-core/src/semantic_analysis/ast_node/declaration/impl_trait.rs
@@ -44,7 +44,7 @@ impl ty::TyImplTrait {
         // Type check the type parameters. This will also insert them into the
         // current namespace.
         let new_impl_type_parameters = check!(
-            TypeParameter::type_check_type_params(ctx.by_ref(), impl_type_parameters, false),
+            TypeParameter::type_check_type_params(ctx.by_ref(), impl_type_parameters),
             return err(warnings, errors),
             warnings,
             errors
@@ -262,7 +262,7 @@ impl ty::TyImplTrait {
         // Type check the type parameters. This will also insert them into the
         // current namespace.
         let new_impl_type_parameters = check!(
-            TypeParameter::type_check_type_params(ctx.by_ref(), impl_type_parameters, false),
+            TypeParameter::type_check_type_params(ctx.by_ref(), impl_type_parameters),
             return err(warnings, errors),
             warnings,
             errors
@@ -300,9 +300,11 @@ impl ty::TyImplTrait {
         );
 
         check!(
-            implementing_for
-                .type_id
-                .check_type_parameter_bounds(&ctx, &implementing_for.span),
+            implementing_for.type_id.check_type_parameter_bounds(
+                &ctx,
+                &implementing_for.span,
+                vec![]
+            ),
             return err(warnings, errors),
             warnings,
             errors
@@ -421,6 +423,23 @@ fn type_check_trait_implementation(
         errors
     );
 
+    for (type_arg, type_param) in trait_type_arguments
+        .clone()
+        .iter()
+        .zip(trait_type_parameters)
+    {
+        check!(
+            type_arg.type_id.check_type_parameter_bounds(
+                &ctx,
+                &type_arg.span(),
+                type_param.trait_constraints.clone()
+            ),
+            return err(warnings, errors),
+            warnings,
+            errors
+        );
+    }
+
     // This map keeps track of the remaining functions in the interface surface
     // that still need to be implemented for the trait to be fully implemented.
     let mut method_checklist: BTreeMap<Ident, ty::TyTraitFn> = BTreeMap::new();

diff --git a/sway-core/src/semantic_analysis/ast_node/declaration/struct.rs b/sway-core/src/semantic_analysis/ast_node/declaration/struct.rs
@@ -30,7 +30,7 @@ impl ty::TyStructDecl {
         // Type check the type parameters. This will also insert them into the
         // current namespace.
         let new_type_parameters = check!(
-            TypeParameter::type_check_type_params(ctx.by_ref(), type_parameters, false),
+            TypeParameter::type_check_type_params(ctx.by_ref(), type_parameters),
             return err(warnings, errors),
             warnings,
             errors

diff --git a/sway-core/src/semantic_analysis/ast_node/declaration/trait.rs b/sway-core/src/semantic_analysis/ast_node/declaration/trait.rs
@@ -56,7 +56,7 @@ impl ty::TyTraitDecl {
         // Type check the type parameters. This will also insert them into the
         // current namespace.
         let new_type_parameters = check!(
-            TypeParameter::type_check_type_params(ctx.by_ref(), type_parameters, true),
+            TypeParameter::type_check_type_params(ctx.by_ref(), type_parameters),
             return err(warnings, errors),
             warnings,
             errors

diff --git a/sway-core/src/semantic_analysis/ast_node/expression/typed_expression/enum_instantiation.rs b/sway-core/src/semantic_analysis/ast_node/expression/typed_expression/enum_instantiation.rs
@@ -110,7 +110,7 @@ pub(crate) fn instantiate_enum(
             let type_id = type_engine.insert(decl_engine, TypeInfo::Enum(enum_ref.clone()));
 
             check!(
-                type_id.check_type_parameter_bounds(&ctx, &enum_variant_name.span()),
+                type_id.check_type_parameter_bounds(&ctx, &enum_variant_name.span(), vec![]),
                 return err(warnings, errors),
                 warnings,
                 errors

diff --git a/sway-core/src/semantic_analysis/ast_node/expression/typed_expression/struct_instantiation.rs b/sway-core/src/semantic_analysis/ast_node/expression/typed_expression/struct_instantiation.rs
@@ -131,7 +131,7 @@ pub(crate) fn struct_instantiation(
     }
 
     check!(
-        type_id.check_type_parameter_bounds(&ctx, &span),
+        type_id.check_type_parameter_bounds(&ctx, &span, vec![]),
         return err(warnings, errors),
         warnings,
         errors

diff --git a/sway-core/src/type_system/ast_elements/type_parameter.rs b/sway-core/src/type_system/ast_elements/type_parameter.rs
@@ -134,20 +134,13 @@ impl TypeParameter {
     pub(crate) fn type_check_type_params(
         mut ctx: TypeCheckContext,
         type_params: Vec<TypeParameter>,
-        disallow_trait_constraints: bool,
     ) -> CompileResult<Vec<TypeParameter>> {
         let mut warnings = vec![];
         let mut errors = vec![];
 
         let mut new_type_params: Vec<TypeParameter> = vec![];
 
         for type_param in type_params.into_iter() {
-            if disallow_trait_constraints && !type_param.trait_constraints.is_empty() {
-                let errors = vec![CompileError::WhereClauseNotYetSupported {
-                    span: type_param.trait_constraints_span,
-                }];
-                return err(vec![], errors);
-            }
             new_type_params.push(check!(
                 TypeParameter::type_check(ctx.by_ref(), type_param),
                 continue,

diff --git a/sway-core/src/type_system/id.rs b/sway-core/src/type_system/id.rs
@@ -363,16 +363,21 @@ impl TypeId {
         &self,
         ctx: &TypeCheckContext,
         span: &Span,
+        trait_constraints: Vec<TraitConstraint>,
     ) -> CompileResult<()> {
         let warnings = vec![];
         let mut errors = vec![];
         let engines = ctx.engines();
 
-        let structure_generics = engines
+        let mut structure_generics = engines
             .te()
             .get(*self)
             .extract_inner_types_with_trait_constraints(engines);
 
+        if !trait_constraints.is_empty() {
+            structure_generics.insert(*self, trait_constraints);
+        }
+
         for (structure_type_id, structure_trait_constraints) in &structure_generics {
             if structure_trait_constraints.is_empty() {
                 continue;

diff --git a/sway-error/src/error.rs b/sway-error/src/error.rs
@@ -564,8 +564,6 @@ pub enum CompileError {
     Lex { error: LexError },
     #[error("{}", error)]
     Parse { error: ParseError },
-    #[error("\"where\" clauses are not yet supported")]
-    WhereClauseNotYetSupported { span: Span },
     #[error("Could not evaluate initializer to a const declaration.")]
     NonConstantDeclValue { span: Span },
     #[error("Declaring storage in a {program_kind} is not allowed.")]
@@ -787,7 +785,6 @@ impl Spanned for CompileError {
             UnexpectedDeclaration { span, .. } => span.clone(),
             ContractAddressMustBeKnown { span, .. } => span.clone(),
             ConvertParseTree { error } => error.span(),
-            WhereClauseNotYetSupported { span, .. } => span.clone(),
             Lex { error } => error.span(),
             Parse { error } => error.span.clone(),
             EnumNotFound { span, .. } => span.clone(),

diff --git a/test/src/e2e_vm_tests/test_programs/should_fail/where_clause_traits/Forc.lock b/test/src/e2e_vm_tests/test_programs/should_fail/where_clause_traits/Forc.lock
@@ -0,0 +1,8 @@
+[[package]]
+name = 'core'
+source = 'path+from-root-8E4C78460FB62C32'
+
+[[package]]
+name = 'where_clause_traits'
+source = 'member'
+dependencies = ['core']
diff --git a/test/src/e2e_vm_tests/test_programs/should_fail/where_clause_traits/Forc.toml b/test/src/e2e_vm_tests/test_programs/should_fail/where_clause_traits/Forc.toml
@@ -0,0 +1,9 @@
+[project]
+name = "where_clause_traits"
+authors = ["Fuel Labs <contact@fuel.sh>"]
+entry = "main.sw"
+license = "Apache-2.0"
+implicit-std = false
+
+[dependencies]
+core = { path = "../../../../../../sway-lib-core" }
diff --git a/test/src/e2e_vm_tests/test_programs/should_fail/where_clause_traits/src/main.sw b/test/src/e2e_vm_tests/test_programs/should_fail/where_clause_traits/src/main.sw
@@ -0,0 +1,30 @@
+script;
+
+trait MyTrait {
+    fn method(self);
+}
+
+trait MyTraitGeneric<T> where T : MyTrait {
+    fn method(self);
+}
+
+struct S1 {
+    s1: u64
+}
+
+impl MyTraitGeneric<S1> for u64 {
+    fn method(self){
+        let s = S1{s1: self};
+        s.method();
+    }
+}
+
+impl<T> MyTraitGeneric<T> for u32 {
+    fn method(self){
+        let s = S1{s1: self};
+        s.method();
+    }
+}
+
+fn main() {
+}
diff --git a/test/src/e2e_vm_tests/test_programs/should_fail/where_clause_traits/test.toml b/test/src/e2e_vm_tests/test_programs/should_fail/where_clause_traits/test.toml
@@ -0,0 +1,8 @@
+category = "fail"
+
+# check: $()impl MyTraitGeneric<S1> for u64 {
+# nextln:$()Trait "MyTrait" is not implemented for type "S1".
+
+# check: $()impl<T> MyTraitGeneric<T> for u32 {
+# nextln: $()Expects trait constraint "T: MyTrait" which is missing from type parameter "T".
+
diff --git a/test/src/e2e_vm_tests/test_programs/should_pass/language/where_clause_traits/Forc.lock b/test/src/e2e_vm_tests/test_programs/should_pass/language/where_clause_traits/Forc.lock
@@ -0,0 +1,13 @@
+[[package]]
+name = 'core'
+source = 'path+from-root-8E4C78460FB62C32'
+
+[[package]]
+name = 'std'
+source = 'path+from-root-8E4C78460FB62C32'
+dependencies = ['core']
+
+[[package]]
+name = 'where_clause_traits'
+source = 'member'
+dependencies = ['std']
diff --git a/test/src/e2e_vm_tests/test_programs/should_pass/language/where_clause_traits/Forc.toml b/test/src/e2e_vm_tests/test_programs/should_pass/language/where_clause_traits/Forc.toml
@@ -0,0 +1,8 @@
+[project]
+name = "where_clause_traits"
+authors = ["Fuel Labs <contact@fuel.sh>"]
+entry = "main.sw"
+license = "Apache-2.0"
+
+[dependencies]
+std = { path = "../../../../../../../sway-lib-std" }
diff --git a/.../e2e_vm_tests/test_programs/should_pass/language/where_clause_traits/json_abi_oracle.json b/.../e2e_vm_tests/test_programs/should_pass/language/where_clause_traits/json_abi_oracle.json
@@ -0,0 +1,25 @@
+{
+  "configurables": [],
+  "functions": [
+    {
+      "attributes": null,
+      "inputs": [],
+      "name": "main",
+      "output": {
+        "name": "",
+        "type": 0,
+        "typeArguments": null
+      }
+    }
+  ],
+  "loggedTypes": [],
+  "messagesTypes": [],
+  "types": [
+    {
+      "components": null,
+      "type": "u8",
+      "typeId": 0,
+      "typeParameters": null
+    }
+  ]
+}
diff --git a/test/src/e2e_vm_tests/test_programs/should_pass/language/where_clause_traits/src/main.sw b/test/src/e2e_vm_tests/test_programs/should_pass/language/where_clause_traits/src/main.sw
@@ -0,0 +1,31 @@
+script;
+
+trait MyTrait {
+    fn new() -> Self;
+}
+
+trait MyTraitGeneric<T> where T : MyTrait {
+    fn get_value(self) -> T;
+}
+
+struct S1 {
+    s1: u64
+}
+
+impl MyTrait for S1 {
+    fn new() -> Self {
+        S1 {s1: 0}
+    }
+}
+
+impl MyTraitGeneric<S1> for u64 {
+    fn get_value(self) -> S1 {
+        S1::new()
+    }
+}
+
+fn main() -> u8 {
+    let _s0: S1 = 42u64.get_value();
+
+    0u8
+}
diff --git a/test/src/e2e_vm_tests/test_programs/should_pass/language/where_clause_traits/test.toml b/test/src/e2e_vm_tests/test_programs/should_pass/language/where_clause_traits/test.toml
@@ -0,0 +1,5 @@
+category = "run"
+expected_result = { action = "return", value = 0 }
+validate_abi = true
+
+expected_warnings = 1