Resolve alias declarations when resolving struct symbols.

sway-core/src/language/parsed/declaration.rs

@@ -33,6 +33,7 @@ use crate::{
     decl_engine::{
         parsed_engine::{ParsedDeclEngine, ParsedDeclEngineGet},
         parsed_id::ParsedDeclId,
+        DeclEngineGetParsedDeclId,
     },
     engine_threading::{
         DebugWithEngines, DisplayWithEngines, EqWithEngines, PartialEqWithEngines,
@@ -142,6 +143,22 @@ impl Declaration {
     ) -> Result<ParsedDeclId<StructDeclaration>, ErrorEmitted> {
         match self {
             Declaration::StructDeclaration(decl_id) => Ok(*decl_id),
+            Declaration::TypeAliasDeclaration(decl_id) => {
+                let alias = engines.pe().get_type_alias(decl_id);
+                let struct_decl_id = engines.te().get(alias.ty.type_id).expect_struct(
+                    handler,
+                    engines,
+                    &self.span(engines),
+                )?;
+
+                let parsed_decl_id = engines.de().get_parsed_decl_id(&struct_decl_id);
+                parsed_decl_id.ok_or_else(|| {
+                    handler.emit_err(CompileError::InternalOwned(
+                        "Cannot get parsed decl id from decl id".to_string(),
+                        self.span(engines),
+                    ))
+                })
+            }
             decl => Err(handler.emit_err(CompileError::DeclIsNotAStruct {
                 actually: decl.friendly_type_name().to_string(),
                 span: decl.span(engines),

sway-core/src/language/ty/declaration/declaration.rs

@@ -555,7 +555,7 @@ impl TyDecl {
     /// Retrieves the declaration as a `DeclRef<DeclId<TyStructDecl>>`.
     ///
     /// Returns an error if `self` is not the [TyDecl][StructDecl] variant.
-    pub(crate) fn to_struct_id(
+    pub(crate) fn to_struct_decl(
         &self,
         handler: &Handler,
         engines: &Engines,

sway-core/src/semantic_analysis/ast_node/declaration/auto_impl.rs

@@ -405,7 +405,7 @@ where
             return Some((None, None));
         }
 
-        let implementing_for_decl_id = decl.to_struct_id(&Handler::default(), engines).unwrap();
+        let implementing_for_decl_id = decl.to_struct_decl(&Handler::default(), engines).unwrap();
         let struct_decl = self.ctx.engines().de().get(&implementing_for_decl_id);
 
         let program_id = struct_decl.span().source_id().map(|sid| sid.program_id());

sway-core/src/semantic_analysis/ast_node/expression/match_expression/typed/typed_scrutinee.rs

@@ -233,7 +233,7 @@ fn type_check_struct(
     let unknown_decl =
         ctx.namespace()
             .resolve_symbol_typed(handler, engines, &struct_name, ctx.self_type())?;
-    let struct_id = unknown_decl.to_struct_id(handler, ctx.engines())?;
+    let struct_id = unknown_decl.to_struct_decl(handler, ctx.engines())?;
     let mut struct_decl = (*decl_engine.get_struct(&struct_id)).clone();
 
     // monomorphize the struct definition

sway-core/src/semantic_analysis/ast_node/expression/typed_expression.rs

@@ -1108,7 +1108,7 @@ impl ty::TyExpression {
                 None,
             )?
             .expect_typed();
-        let storage_key_struct_decl_ref = storage_key_decl_opt.to_struct_id(handler, engines)?;
+        let storage_key_struct_decl_ref = storage_key_decl_opt.to_struct_decl(handler, engines)?;
         let mut storage_key_struct_decl =
             (*decl_engine.get_struct(&storage_key_struct_decl_ref)).clone();
 

sway-core/src/semantic_analysis/namespace/root.rs

@@ -8,7 +8,7 @@ use crate::{
     engine_threading::*,
     language::{
         parsed::*,
-        ty::{self, TyDecl, TyTraitItem},
+        ty::{self, StructDecl, TyDecl, TyTraitItem},
         CallPath, Visibility,
     },
     namespace::{ModulePath, ModulePathBuf},
@@ -99,6 +99,23 @@ impl ResolvedDeclaration {
         }
     }
 
+    pub(crate) fn to_struct_decl(
+        &self,
+        handler: &Handler,
+        engines: &Engines,
+    ) -> Result<ResolvedDeclaration, ErrorEmitted> {
+        match self {
+            ResolvedDeclaration::Parsed(decl) => decl
+                .to_struct_decl(handler, engines)
+                .map(|id| ResolvedDeclaration::Parsed(Declaration::StructDeclaration(id.clone()))),
+            ResolvedDeclaration::Typed(decl) => decl.to_struct_decl(handler, engines).map(|id| {
+                ResolvedDeclaration::Typed(TyDecl::StructDecl(StructDecl {
+                    decl_id: id.clone(),
+                }))
+            }),
+        }
+    }
+
     pub(crate) fn visibility(&self, engines: &Engines) -> Visibility {
         match self {
             ResolvedDeclaration::Parsed(decl) => decl.visibility(engines.pe()),

sway-core/src/type_system/ast_elements/binding.rs

@@ -363,11 +363,14 @@ impl SymbolResolveTypeBinding<StructDeclaration> for TypeBinding<CallPath> {
         let engines = ctx.engines();
         // Grab the declaration.
         let unknown_decl = ctx.resolve_call_path_with_visibility_check(handler, &self.inner)?;
+
         // Check to see if this is a struct declaration.
-        let struct_decl_id = unknown_decl
+        let struct_decl = unknown_decl.to_struct_decl(handler, engines)?;
+        eprintln!("{:#?}", struct_decl);
+
+        Ok(struct_decl
             .resolve_parsed(engines.de())
-            .to_struct_decl(handler, engines)?;
-        Ok(struct_decl_id)
+            .to_struct_decl(handler, engines)?)
     }
 }
 
@@ -390,7 +393,7 @@ impl TypeCheckTypeBinding<ty::TyStructDecl> for TypeBinding<CallPath> {
         // Grab the declaration.
         let unknown_decl = ctx.resolve_call_path_with_visibility_check(handler, &self.inner)?;
         // Check to see if this is a struct declaration.
-        let struct_id = unknown_decl.to_struct_id(handler, engines)?;
+        let struct_id = unknown_decl.to_struct_decl(handler, engines)?;
         // Get a new copy from the declaration engine.
         let mut new_copy = (*decl_engine.get_struct(&struct_id)).clone();
         // Monomorphize the copy, in place.

test/src/e2e_vm_tests/test_programs/should_pass/language/type_alias_basic/Forc.lock

@@ -0,0 +1,8 @@
+[[package]]
+name = "alias"
+source = "path+from-root-DE984AFD05391BAA"
+
+[[package]]
+name = "use-alias"
+source = "member"
+dependencies = ["alias"]

test/src/e2e_vm_tests/test_programs/should_pass/language/type_alias_basic/Forc.toml

@@ -0,0 +1,6 @@
+[project]
+authors = ["Fuel Labs <contact@fuel.sh>"]
+entry = "main.sw"
+license = "Apache-2.0"
+name = "type_alias_basic"
+implicit-std = false

test/src/e2e_vm_tests/test_programs/should_pass/language/type_alias_basic/src/main.sw

@@ -0,0 +1,4 @@
+library;
+
+struct S {}
+pub type Alias = S;

test/src/e2e_vm_tests/test_programs/should_pass/language/type_alias_from_dependency/Forc.lock

@@ -0,0 +1,8 @@
+[[package]]
+name = "type_alias_basic"
+source = "path+from-root-05B061D32AED907C"
+
+[[package]]
+name = "type_alias_from_dependency"
+source = "member"
+dependencies = ["type_alias_basic"]

test/src/e2e_vm_tests/test_programs/should_pass/language/type_alias_from_dependency/Forc.toml

@@ -0,0 +1,9 @@
+[project]
+authors = ["Fuel Labs <contact@fuel.sh>"]
+entry = "main.sw"
+license = "Apache-2.0"
+name = "type_alias_from_dependency"
+implicit-std = false
+
+[dependencies]
+type_alias_basic = { path = "../type_alias_basic" }

test/src/e2e_vm_tests/test_programs/should_pass/language/type_alias_from_dependency/src/main.sw

@@ -0,0 +1,7 @@
+library;
+
+use type_alias_basic::*;
+
+fn foo() {
+    let z = type_alias_basic::Alias { };
+}

test/src/e2e_vm_tests/test_programs/should_pass/language/type_alias_from_dependency/test.toml

@@ -0,0 +1,3 @@
+category = "compile"
+validate_abi = false
+expected_warnings = 2