Add ProgramBuilder::Alias()

Combines the calls to ty.alias() and AST().AddConstructedType()

Change-Id: I84eaf6275d37141cf8973db7e04d25d9cb9c6351
Reviewed-on: https://dawn-review.googlesource.com/c/tint/+/53801
Commit-Queue: Ben Clayton <bclayton@google.com>
Kokoro: Kokoro <noreply+kokoro@google.com>
Reviewed-by: Antonio Maiorano <amaiorano@google.com>
diff --git a/src/ast/alias_test.cc b/src/ast/alias_test.cc
index d3c5ec7..e55428d 100644
--- a/src/ast/alias_test.cc
+++ b/src/ast/alias_test.cc
@@ -35,7 +35,7 @@
 
 TEST_F(AstAliasTest, Create) {
   auto* u32 = create<U32>();
-  auto* a = create<Alias>(Sym("a_type"), u32);
+  auto* a = Alias("a_type", u32);
   EXPECT_EQ(a->symbol(), Symbol(1, ID()));
   EXPECT_EQ(a->type(), u32);
 }
@@ -46,7 +46,7 @@
 TEST_F(AstAliasTest, TypeName_LinearTime) {
   Type* type = ty.i32();
   for (int i = 0; i < 1024; i++) {
-    type = create<Alias>(Symbols().New(), type);
+    type = Alias(Symbols().New(), type);
   }
   for (int i = 0; i < 16384; i++) {
     type->type_name();
@@ -54,22 +54,22 @@
 }
 
 TEST_F(AstAliasTest, TypeName) {
-  auto* at = create<Alias>(Sym("Particle"), create<I32>());
+  auto* at = Alias("Particle", create<I32>());
   EXPECT_EQ(at->type_name(), "__alias_$1__i32");
 }
 
 TEST_F(AstAliasTest, FriendlyName) {
-  auto* at = create<Alias>(Sym("Particle"), create<I32>());
+  auto* at = Alias("Particle", create<I32>());
   EXPECT_EQ(at->FriendlyName(Symbols()), "Particle");
 }
 
 TEST_F(AstAliasTest, UnwrapAll_TwiceAliasPointerTwiceAlias) {
   auto* u32 = create<U32>();
-  auto* a = create<Alias>(Sym("a_type"), u32);
-  auto* aa = create<Alias>(Sym("aa_type"), a);
+  auto* a = create<ast::Alias>(Sym("a_type"), u32);
+  auto* aa = create<ast::Alias>(Sym("aa_type"), a);
   auto* paa = create<Pointer>(aa, StorageClass::kUniform, Access::kUndefined);
-  auto* apaa = create<Alias>(Sym("paa_type"), paa);
-  auto* aapaa = create<Alias>(Sym("aapaa_type"), apaa);
+  auto* apaa = create<ast::Alias>(Sym("paa_type"), paa);
+  auto* aapaa = create<ast::Alias>(Sym("aapaa_type"), apaa);
 
   EXPECT_EQ(aapaa->symbol(), Symbol(4, ID()));
   EXPECT_EQ(aapaa->type(), apaa);
diff --git a/src/program_builder.h b/src/program_builder.h
index 82814a7..4a9c3d0 100644
--- a/src/program_builder.h
+++ b/src/program_builder.h
@@ -1620,6 +1620,29 @@
     return create<ast::ReturnStatement>(Expr(std::forward<EXPR>(val)));
   }
 
+  /// Creates a ast::Alias registering it with the AST().ConstructedTypes().
+  /// @param source the source information
+  /// @param name the alias name
+  /// @param type the alias target type
+  /// @returns the alias type
+  template <typename NAME>
+  ast::Alias* Alias(const Source& source, NAME&& name, ast::Type* type) {
+    auto* out = ty.alias(source, std::forward<NAME>(name), type);
+    AST().AddConstructedType(out);
+    return out;
+  }
+
+  /// Creates a ast::Alias registering it with the AST().ConstructedTypes().
+  /// @param name the alias name
+  /// @param type the alias target type
+  /// @returns the alias type
+  template <typename NAME>
+  ast::Alias* Alias(NAME&& name, ast::Type* type) {
+    auto* out = ty.alias(std::forward<NAME>(name), type);
+    AST().AddConstructedType(out);
+    return out;
+  }
+
   /// Creates a ast::Struct registering it with the AST().ConstructedTypes().
   /// @param source the source information
   /// @param name the struct name
diff --git a/src/resolver/assignment_validation_test.cc b/src/resolver/assignment_validation_test.cc
index b270ec9..7c124b4 100644
--- a/src/resolver/assignment_validation_test.cc
+++ b/src/resolver/assignment_validation_test.cc
@@ -111,8 +111,7 @@
   // alias myint = i32;
   // var a : myint = 2;
   // a = 2
-  auto* myint = ty.alias("myint", ty.i32());
-  AST().AddConstructedType(myint);
+  auto* myint = Alias("myint", ty.i32());
   auto* var = Var("a", myint, ast::StorageClass::kNone, Expr(2));
   WrapInFunction(var, Assign(Source{{12, 34}}, "a", 2));
 
diff --git a/src/resolver/control_block_validation_test.cc b/src/resolver/control_block_validation_test.cc
index a999fbb..a7e7847 100644
--- a/src/resolver/control_block_validation_test.cc
+++ b/src/resolver/control_block_validation_test.cc
@@ -294,7 +294,7 @@
   //   default: {}
   // }
 
-  auto* my_int = ty.alias("MyInt", ty.u32());
+  auto* my_int = Alias("MyInt", ty.u32());
   auto* var = Var("a", my_int, ast::StorageClass::kNone, Expr(2u));
 
   ast::CaseSelectorList default_csl;
@@ -304,7 +304,6 @@
                                             default_csl, block_default));
 
   auto* block = Block(Decl(var), create<ast::SwitchStatement>(Expr("a"), body));
-  AST().AddConstructedType(my_int);
 
   WrapInFunction(block);
 
diff --git a/src/resolver/function_validation_test.cc b/src/resolver/function_validation_test.cc
index 1bb927c..94e6791 100644
--- a/src/resolver/function_validation_test.cc
+++ b/src/resolver/function_validation_test.cc
@@ -230,8 +230,7 @@
        FunctionTypeMustMatchReturnStatementTypeF32Alias_pass) {
   // type myf32 = f32;
   // fn func -> myf32 { return 2.0; }
-  auto* myf32 = ty.alias("myf32", ty.f32());
-  AST().AddConstructedType(myf32);
+  auto* myf32 = Alias("myf32", ty.f32());
   Func("func", ast::VariableList{}, myf32,
        ast::StatementList{
            Return(Source{Source::Location{12, 34}}, Expr(2.f)),
@@ -245,8 +244,7 @@
        FunctionTypeMustMatchReturnStatementTypeF32Alias_fail) {
   // type myf32 = f32;
   // fn func -> myf32 { return 2; }
-  auto* myf32 = ty.alias("myf32", ty.f32());
-  AST().AddConstructedType(myf32);
+  auto* myf32 = Alias("myf32", ty.f32());
   Func("func", ast::VariableList{}, myf32,
        ast::StatementList{
            Return(Source{Source::Location{12, 34}}, Expr(2u)),
diff --git a/src/resolver/host_shareable_validation_test.cc b/src/resolver/host_shareable_validation_test.cc
index 57e6fbc..e783f1d 100644
--- a/src/resolver/host_shareable_validation_test.cc
+++ b/src/resolver/host_shareable_validation_test.cc
@@ -66,12 +66,10 @@
 }
 
 TEST_F(ResolverHostShareableValidationTest, Aliases) {
-  auto* a1 = ty.alias("a1", ty.bool_());
-  AST().AddConstructedType(a1);
+  auto* a1 = Alias("a1", ty.bool_());
   auto* s = Structure("S", {Member(Source{{12, 34}}, "x", a1)},
                       {create<ast::StructBlockDecoration>()});
-  auto* a2 = ty.alias("a2", s);
-  AST().AddConstructedType(a2);
+  auto* a2 = Alias("a2", s);
   Global(Source{{56, 78}}, "g", a2, ast::StorageClass::kStorage,
          ast::Access::kRead,
          ast::DecorationList{
@@ -122,14 +120,12 @@
                           Member(Source{{2, 1}}, "y1", ty.vec3<f32>()),
                           Member(Source{{3, 1}}, "z1", ty.array<i32, 4>()),
                       });
-  auto* a1 = ty.alias("a1", i1);
-  AST().AddConstructedType(a1);
+  auto* a1 = Alias("a1", i1);
   auto* i2 = Structure("I2", {
                                  Member(Source{{4, 1}}, "x2", ty.mat2x2<f32>()),
                                  Member(Source{{5, 1}}, "y2", i1),
                              });
-  auto* a2 = ty.alias("a2", i2);
-  AST().AddConstructedType(a2);
+  auto* a2 = Alias("a2", i2);
   auto* i3 = Structure("I3", {
                                  Member(Source{{4, 1}}, "x3", a1),
                                  Member(Source{{5, 1}}, "y3", i2),
diff --git a/src/resolver/resolver_test.cc b/src/resolver/resolver_test.cc
index 91b8195..f7ed724 100644
--- a/src/resolver/resolver_test.cc
+++ b/src/resolver/resolver_test.cc
@@ -293,8 +293,7 @@
 }
 
 TEST_F(ResolverTest, Stmt_VariableDecl_Alias) {
-  auto* my_int = ty.alias("MyInt", ty.i32());
-  AST().AddConstructedType(my_int);
+  auto* my_int = Alias("MyInt", ty.i32());
   auto* var = Var("my_var", my_int, ast::StorageClass::kNone, Expr(2));
   auto* init = var->constructor();
 
@@ -308,10 +307,8 @@
 }
 
 TEST_F(ResolverTest, Stmt_VariableDecl_AliasRedeclared) {
-  auto* my_int1 = ty.alias(Source{{12, 34}}, "MyInt", ty.i32());
-  auto* my_int2 = ty.alias(Source{{56, 78}}, "MyInt", ty.i32());
-  AST().AddConstructedType(my_int1);
-  AST().AddConstructedType(my_int2);
+  Alias(Source{{12, 34}}, "MyInt", ty.i32());
+  Alias(Source{{56, 78}}, "MyInt", ty.i32());
   WrapInFunction();
 
   EXPECT_FALSE(r()->Resolve());
@@ -450,8 +447,7 @@
 }
 
 TEST_F(ResolverTest, Expr_ArrayAccessor_Alias_Array) {
-  auto* aary = ty.alias("myarrty", ty.array<f32, 3>());
-  AST().AddConstructedType(aary);
+  auto* aary = Alias("myarrty", ty.array<f32, 3>());
 
   Global("my_var", aary, ast::StorageClass::kPrivate);
 
@@ -1124,8 +1120,7 @@
 TEST_F(ResolverTest, Expr_MemberAccessor_Struct_Alias) {
   auto* st = Structure("S", {Member("first_member", ty.i32()),
                              Member("second_member", ty.f32())});
-  auto* alias = ty.alias("alias", st);
-  AST().AddConstructedType(alias);
+  auto* alias = Alias("alias", st);
   Global("my_struct", alias, ast::StorageClass::kInput);
 
   auto* mem = MemberAccessor("my_struct", "second_member");
diff --git a/src/resolver/storage_class_validation_test.cc b/src/resolver/storage_class_validation_test.cc
index 29c8945..033e7f6 100644
--- a/src/resolver/storage_class_validation_test.cc
+++ b/src/resolver/storage_class_validation_test.cc
@@ -86,8 +86,7 @@
 TEST_F(ResolverStorageClassValidationTest, StorageBufferBoolAlias) {
   // type a = bool;
   // var<storage, read> g : a;
-  auto* a = ty.alias("a", ty.bool_());
-  AST().AddConstructedType(a);
+  auto* a = Alias("a", ty.bool_());
   Global(Source{{56, 78}}, "g", a, ast::StorageClass::kStorage,
          ast::DecorationList{
              create<ast::BindingDecoration>(0),
@@ -141,10 +140,8 @@
   // var<storage, read> g : a1;
   auto* s = Structure("S", {Member(Source{{12, 34}}, "x", ty.i32())},
                       {create<ast::StructBlockDecoration>()});
-  auto* a1 = ty.alias("a1", s);
-  AST().AddConstructedType(a1);
-  auto* a2 = ty.alias("a2", a1);
-  AST().AddConstructedType(a2);
+  auto* a1 = Alias("a1", s);
+  auto* a2 = Alias("a2", a1);
   Global(Source{{56, 78}}, "g", a2, ast::StorageClass::kStorage,
          ast::Access::kRead,
          ast::DecorationList{
@@ -208,8 +205,7 @@
 TEST_F(ResolverStorageClassValidationTest, UniformBufferBoolAlias) {
   // type a = bool;
   // var<uniform> g : a;
-  auto* a = ty.alias("a", ty.bool_());
-  AST().AddConstructedType(a);
+  auto* a = Alias("a", ty.bool_());
   Global(Source{{56, 78}}, "g", a, ast::StorageClass::kUniform,
          ast::DecorationList{
              create<ast::BindingDecoration>(0),
@@ -261,8 +257,7 @@
   // var<uniform> g : a1;
   auto* s = Structure("S", {Member(Source{{12, 34}}, "x", ty.i32())},
                       {create<ast::StructBlockDecoration>()});
-  auto* a1 = ty.alias("a1", s);
-  AST().AddConstructedType(a1);
+  auto* a1 = Alias("a1", s);
   Global(Source{{56, 78}}, "g", a1, ast::StorageClass::kUniform,
          ast::DecorationList{
              create<ast::BindingDecoration>(0),
diff --git a/src/resolver/struct_layout_test.cc b/src/resolver/struct_layout_test.cc
index 667020c..be0e808 100644
--- a/src/resolver/struct_layout_test.cc
+++ b/src/resolver/struct_layout_test.cc
@@ -52,10 +52,8 @@
 }
 
 TEST_F(ResolverStructLayoutTest, Alias) {
-  auto* alias_a = ty.alias("a", ty.f32());
-  AST().AddConstructedType(alias_a);
-  auto* alias_b = ty.alias("b", ty.f32());
-  AST().AddConstructedType(alias_b);
+  auto* alias_a = Alias("a", ty.f32());
+  auto* alias_b = Alias("b", ty.f32());
 
   auto* s = Structure("S", {
                                Member("a", alias_a),
diff --git a/src/resolver/struct_pipeline_stage_use_test.cc b/src/resolver/struct_pipeline_stage_use_test.cc
index b6d5655..4c481a5 100644
--- a/src/resolver/struct_pipeline_stage_use_test.cc
+++ b/src/resolver/struct_pipeline_stage_use_test.cc
@@ -158,8 +158,7 @@
 
 TEST_F(ResolverPipelineStageUseTest, StructUsedAsShaderParamViaAlias) {
   auto* s = Structure("S", {Member("a", ty.f32(), {Location(0)})});
-  auto* s_alias = ty.alias("S_alias", s);
-  AST().AddConstructedType(s_alias);
+  auto* s_alias = Alias("S_alias", s);
 
   Func("main", {Param("param", s_alias)}, ty.void_(), {},
        {Stage(ast::PipelineStage::kFragment)});
@@ -174,8 +173,7 @@
 
 TEST_F(ResolverPipelineStageUseTest, StructUsedAsShaderReturnTypeViaAlias) {
   auto* s = Structure("S", {Member("a", ty.f32(), {Location(0)})});
-  auto* s_alias = ty.alias("S_alias", s);
-  AST().AddConstructedType(s_alias);
+  auto* s_alias = Alias("S_alias", s);
 
   Func("main", {}, s_alias, {Return(Construct(s_alias, Expr(0.f)))},
        {Stage(ast::PipelineStage::kFragment)});
diff --git a/src/resolver/struct_storage_class_use_test.cc b/src/resolver/struct_storage_class_use_test.cc
index 7a83ab0..8af99be 100644
--- a/src/resolver/struct_storage_class_use_test.cc
+++ b/src/resolver/struct_storage_class_use_test.cc
@@ -78,8 +78,7 @@
 
 TEST_F(ResolverStorageClassUseTest, StructReachableViaGlobalAlias) {
   auto* s = Structure("S", {Member("a", ty.f32())});
-  auto* a = ty.alias("A", s);
-  AST().AddConstructedType(a);
+  auto* a = Alias("A", s);
   Global("g", a, ast::StorageClass::kPrivate);
 
   ASSERT_TRUE(r()->Resolve()) << r()->error();
@@ -131,8 +130,7 @@
 
 TEST_F(ResolverStorageClassUseTest, StructReachableViaLocalAlias) {
   auto* s = Structure("S", {Member("a", ty.f32())});
-  auto* a = ty.alias("A", s);
-  AST().AddConstructedType(a);
+  auto* a = Alias("A", s);
   WrapInFunction(Var("g", a));
 
   ASSERT_TRUE(r()->Resolve()) << r()->error();
diff --git a/src/resolver/type_validation_test.cc b/src/resolver/type_validation_test.cc
index 5c9973e..2eb0707 100644
--- a/src/resolver/type_validation_test.cc
+++ b/src/resolver/type_validation_test.cc
@@ -338,9 +338,7 @@
   //  a: u32;
   //}
 
-  auto* alias = ty.alias("RTArr", ty.array<u32>());
-  AST().AddConstructedType(alias);
-
+  auto* alias = Alias("RTArr", ty.array<u32>());
   Structure("s",
             {
                 Member(Source{{12, 34}}, "b", alias),
@@ -365,9 +363,7 @@
   //  b: RTArr;
   //}
 
-  auto* alias = ty.alias("RTArr", ty.array<u32>());
-  AST().AddConstructedType(alias);
-
+  auto* alias = Alias("RTArr", ty.array<u32>());
   Structure("s",
             {
                 Member("a", ty.u32()),
diff --git a/src/resolver/validation_test.cc b/src/resolver/validation_test.cc
index 07356a7..e271bdc 100644
--- a/src/resolver/validation_test.cc
+++ b/src/resolver/validation_test.cc
@@ -1708,8 +1708,7 @@
 }
 
 TEST_F(ResolverValidationTest, Expr_Constructor_Vector_Alias_Argument_Error) {
-  auto* alias = ty.alias("UnsignedInt", ty.u32());
-  AST().AddConstructedType(alias);
+  auto* alias = Alias("UnsignedInt", ty.u32());
   Global("uint_var", alias, ast::StorageClass::kInput);
 
   auto* tc = vec2<f32>(Expr(Source{{12, 34}}, "uint_var"));
@@ -1722,10 +1721,8 @@
 }
 
 TEST_F(ResolverValidationTest, Expr_Constructor_Vector_Alias_Argument_Success) {
-  auto* f32_alias = ty.alias("Float32", ty.f32());
-  auto* vec2_alias = ty.alias("VectorFloat2", ty.vec2<f32>());
-  AST().AddConstructedType(f32_alias);
-  AST().AddConstructedType(vec2_alias);
+  auto* f32_alias = Alias("Float32", ty.f32());
+  auto* vec2_alias = Alias("VectorFloat2", ty.vec2<f32>());
   Global("my_f32", f32_alias, ast::StorageClass::kInput);
   Global("my_vec2", vec2_alias, ast::StorageClass::kInput);
 
@@ -1735,8 +1732,7 @@
 }
 
 TEST_F(ResolverValidationTest, Expr_Constructor_Vector_ElementTypeAlias_Error) {
-  auto* f32_alias = ty.alias("Float32", ty.f32());
-  AST().AddConstructedType(f32_alias);
+  auto* f32_alias = Alias("Float32", ty.f32());
 
   // vec2<Float32>(1.0f, 1u)
   auto* vec_type = ty.vec(f32_alias, 2);
@@ -1754,8 +1750,7 @@
 
 TEST_F(ResolverValidationTest,
        Expr_Constructor_Vector_ElementTypeAlias_Success) {
-  auto* f32_alias = ty.alias("Float32", ty.f32());
-  AST().AddConstructedType(f32_alias);
+  auto* f32_alias = Alias("Float32", ty.f32());
 
   // vec2<Float32>(1.0f, 1.0f)
   auto* vec_type = ty.vec(f32_alias, 2);
@@ -1768,8 +1763,7 @@
 
 TEST_F(ResolverValidationTest,
        Expr_Constructor_Vector_ArgumentElementTypeAlias_Error) {
-  auto* f32_alias = ty.alias("Float32", ty.f32());
-  AST().AddConstructedType(f32_alias);
+  auto* f32_alias = Alias("Float32", ty.f32());
 
   // vec3<u32>(vec<Float32>(), 1.0f)
   auto* vec_type = ty.vec(f32_alias, 2);
@@ -1786,8 +1780,7 @@
 
 TEST_F(ResolverValidationTest,
        Expr_Constructor_Vector_ArgumentElementTypeAlias_Success) {
-  auto* f32_alias = ty.alias("Float32", ty.f32());
-  AST().AddConstructedType(f32_alias);
+  auto* f32_alias = Alias("Float32", ty.f32());
 
   // vec3<f32>(vec<Float32>(), 1.0f)
   auto* vec_type = ty.vec(f32_alias, 2);
@@ -2017,8 +2010,7 @@
   // matNxM<Float32>(vecM<u32>(), ...); with N arguments
 
   const auto param = GetParam();
-  auto* f32_alias = ty.alias("Float32", ty.f32());
-  AST().AddConstructedType(f32_alias);
+  auto* f32_alias = Alias("Float32", ty.f32());
 
   ast::ExpressionList args;
   for (uint32_t i = 1; i <= param.columns; i++) {
@@ -2043,8 +2035,7 @@
   // matNxM<Float32>(vecM<f32>(), ...); with N arguments
 
   const auto param = GetParam();
-  auto* f32_alias = ty.alias("Float32", ty.f32());
-  AST().AddConstructedType(f32_alias);
+  auto* f32_alias = Alias("Float32", ty.f32());
 
   ast::ExpressionList args;
   for (uint32_t i = 1; i <= param.columns; i++) {
@@ -2062,8 +2053,7 @@
 }
 
 TEST_F(ResolverValidationTest, Expr_MatrixConstructor_ArgumentTypeAlias_Error) {
-  auto* alias = ty.alias("VectorUnsigned2", ty.vec2<u32>());
-  AST().AddConstructedType(alias);
+  auto* alias = Alias("VectorUnsigned2", ty.vec2<u32>());
   auto* tc = mat2x2<f32>(
       create<ast::TypeConstructorExpression>(
           Source{{12, 34}}, ty.MaybeCreateTypename(alias), ExprList()),
@@ -2080,8 +2070,7 @@
   const auto param = GetParam();
   auto* matrix_type = ty.mat<f32>(param.columns, param.rows);
   auto* vec_type = ty.vec<f32>(param.rows);
-  auto* vec_alias = ty.alias("VectorFloat2", vec_type);
-  AST().AddConstructedType(vec_alias);
+  auto* vec_alias = Alias("VectorFloat2", vec_type);
 
   ast::ExpressionList args;
   for (uint32_t i = 1; i <= param.columns; i++) {
@@ -2099,8 +2088,7 @@
 TEST_P(MatrixConstructorTest, Expr_Constructor_ArgumentElementTypeAlias_Error) {
   const auto param = GetParam();
   auto* matrix_type = ty.mat<f32>(param.columns, param.rows);
-  auto* f32_alias = ty.alias("UnsignedInt", ty.u32());
-  AST().AddConstructedType(f32_alias);
+  auto* f32_alias = Alias("UnsignedInt", ty.u32());
 
   ast::ExpressionList args;
   for (uint32_t i = 1; i <= param.columns; i++) {
@@ -2123,8 +2111,7 @@
 TEST_P(MatrixConstructorTest,
        Expr_Constructor_ArgumentElementTypeAlias_Success) {
   const auto param = GetParam();
-  auto* f32_alias = ty.alias("Float32", ty.f32());
-  AST().AddConstructedType(f32_alias);
+  auto* f32_alias = Alias("Float32", ty.f32());
 
   ast::ExpressionList args;
   for (uint32_t i = 1; i <= param.columns; i++) {
diff --git a/src/resolver/var_let_test.cc b/src/resolver/var_let_test.cc
index a351ac3..84b4ae7 100644
--- a/src/resolver/var_let_test.cc
+++ b/src/resolver/var_let_test.cc
@@ -39,8 +39,7 @@
   // }
 
   auto* S = Structure("S", {Member("i", ty.i32())});
-  auto* A = ty.alias("A", S);
-  AST().AddConstructedType(A);
+  auto* A = Alias("A", S);
 
   auto* i = Var("i", ty.i32(), ast::StorageClass::kNone);
   auto* u = Var("u", ty.u32(), ast::StorageClass::kNone);
@@ -91,8 +90,7 @@
   // }
 
   auto* S = Structure("S", {Member("i", ty.i32())});
-  auto* A = ty.alias("A", S);
-  AST().AddConstructedType(A);
+  auto* A = Alias("A", S);
 
   auto* v = Var("v", ty.i32(), ast::StorageClass::kNone);
   auto* i = Const("i", ty.i32(), Expr(1));
diff --git a/src/resolver/var_let_validation_test.cc b/src/resolver/var_let_validation_test.cc
index 96ada20..0fa67e8 100644
--- a/src/resolver/var_let_validation_test.cc
+++ b/src/resolver/var_let_validation_test.cc
@@ -80,8 +80,7 @@
 }
 
 TEST_F(ResolverVarLetValidationTest, LetConstructorWrongTypeViaAlias) {
-  auto* a = ty.alias("I32", ty.i32());
-  AST().AddConstructedType(a);
+  auto* a = Alias("I32", ty.i32());
   WrapInFunction(Const(Source{{3, 3}}, "v", a, Expr(2u)));
 
   EXPECT_FALSE(r()->Resolve());
@@ -91,8 +90,7 @@
 }
 
 TEST_F(ResolverVarLetValidationTest, VarConstructorWrongTypeViaAlias) {
-  auto* a = ty.alias("I32", ty.i32());
-  AST().AddConstructedType(a);
+  auto* a = Alias("I32", ty.i32());
   WrapInFunction(
       Var(Source{{3, 3}}, "v", a, ast::StorageClass::kNone, Expr(2u)));
 
diff --git a/src/writer/hlsl/generator_impl_workgroup_var_test.cc b/src/writer/hlsl/generator_impl_workgroup_var_test.cc
index a488f10..f48920d 100644
--- a/src/writer/hlsl/generator_impl_workgroup_var_test.cc
+++ b/src/writer/hlsl/generator_impl_workgroup_var_test.cc
@@ -39,8 +39,7 @@
 }
 
 TEST_F(HlslGeneratorImplTest_WorkgroupVar, Aliased) {
-  auto* alias = ty.alias("F32", ty.f32());
-  AST().AddConstructedType(alias);
+  auto* alias = Alias("F32", ty.f32());
 
   Global("wg", alias, ast::StorageClass::kWorkgroup);
 
diff --git a/src/writer/spirv/builder_accessor_expression_test.cc b/src/writer/spirv/builder_accessor_expression_test.cc
index b7400ee..19da1a4 100644
--- a/src/writer/spirv/builder_accessor_expression_test.cc
+++ b/src/writer/spirv/builder_accessor_expression_test.cc
@@ -394,8 +394,7 @@
                                               Member("b", ty.f32()),
                                           });
 
-  auto* alias = ty.alias("Alias", inner_struct);
-  AST().AddConstructedType(alias);
+  auto* alias = Alias("Alias", inner_struct);
   auto* s_type = Structure("Outer", {Member("inner", alias)});
 
   auto* var = Var("ident", s_type);
diff --git a/src/writer/spirv/builder_constructor_expression_test.cc b/src/writer/spirv/builder_constructor_expression_test.cc
index 2669331..5dd4be6 100644
--- a/src/writer/spirv/builder_constructor_expression_test.cc
+++ b/src/writer/spirv/builder_constructor_expression_test.cc
@@ -93,8 +93,7 @@
   // type Int = i32
   // cast<Int>(2.3f)
 
-  auto* alias = ty.alias("Int", ty.i32());
-  AST().AddConstructedType(alias);
+  auto* alias = Alias("Int", ty.i32());
   auto* cast = Construct(alias, 2.3f);
   WrapInFunction(cast);
 
diff --git a/src/writer/spirv/builder_global_variable_test.cc b/src/writer/spirv/builder_global_variable_test.cc
index 6cc49f9d..9aa0bca 100644
--- a/src/writer/spirv/builder_global_variable_test.cc
+++ b/src/writer/spirv/builder_global_variable_test.cc
@@ -441,8 +441,7 @@
 
   auto* A = Structure("A", {Member("a", ty.i32())},
                       {create<ast::StructBlockDecoration>()});
-  auto* B = ty.alias("B", A);
-  AST().AddConstructedType(B);
+  auto* B = Alias("B", A);
   auto* var = Global("b", B, ast::StorageClass::kStorage, ast::Access::kRead,
                      ast::DecorationList{
                          create<ast::BindingDecoration>(0),
@@ -479,8 +478,7 @@
 
   auto* A = Structure("A", {Member("a", ty.i32())},
                       {create<ast::StructBlockDecoration>()});
-  auto* B = ty.alias("B", A);
-  AST().AddConstructedType(B);
+  auto* B = Alias("B", A);
   auto* var = Global("b", B, ast::StorageClass::kStorage, ast::Access::kRead,
                      ast::DecorationList{
                          create<ast::BindingDecoration>(0),
diff --git a/src/writer/wgsl/generator_impl_alias_type_test.cc b/src/writer/wgsl/generator_impl_alias_type_test.cc
index 4b7311b..f71ee45 100644
--- a/src/writer/wgsl/generator_impl_alias_type_test.cc
+++ b/src/writer/wgsl/generator_impl_alias_type_test.cc
@@ -22,8 +22,7 @@
 using WgslGeneratorImplTest = TestHelper;
 
 TEST_F(WgslGeneratorImplTest, EmitAlias_F32) {
-  auto* alias = ty.alias("a", ty.f32());
-  AST().AddConstructedType(alias);
+  auto* alias = Alias("a", ty.f32());
   GeneratorImpl& gen = Build();
 
   ASSERT_TRUE(gen.EmitConstructedType(alias)) << gen.error();
@@ -37,8 +36,7 @@
                                Member("b", ty.i32()),
                            });
 
-  auto* alias = ty.alias("B", s);
-  AST().AddConstructedType(alias);
+  auto* alias = Alias("B", s);
 
   GeneratorImpl& gen = Build();
 
@@ -58,8 +56,7 @@
                                Member("b", ty.i32()),
                            });
 
-  auto* alias = ty.alias("B", s);
-  AST().AddConstructedType(alias);
+  auto* alias = Alias("B", s);
 
   GeneratorImpl& gen = Build();
 
diff --git a/src/writer/wgsl/generator_impl_type_test.cc b/src/writer/wgsl/generator_impl_type_test.cc
index 5494e7b..9acd634 100644
--- a/src/writer/wgsl/generator_impl_type_test.cc
+++ b/src/writer/wgsl/generator_impl_type_test.cc
@@ -26,8 +26,7 @@
 using WgslGeneratorImplTest = TestHelper;
 
 TEST_F(WgslGeneratorImplTest, EmitType_Alias) {
-  auto* alias = ty.alias("alias", ty.f32());
-  AST().AddConstructedType(alias);
+  auto* alias = Alias("alias", ty.f32());
 
   GeneratorImpl& gen = Build();
 
@@ -37,7 +36,7 @@
 
 TEST_F(WgslGeneratorImplTest, EmitType_Array) {
   auto* arr = ty.array<bool, 4>();
-  AST().AddConstructedType(ty.alias("make_type_reachable", arr));
+  Alias("make_type_reachable", arr);
 
   GeneratorImpl& gen = Build();
 
@@ -47,7 +46,7 @@
 
 TEST_F(WgslGeneratorImplTest, EmitType_Array_Decoration) {
   auto* a = ty.array(ty.bool_(), 4, 16u);
-  AST().AddConstructedType(ty.alias("make_type_reachable", a));
+  Alias("make_type_reachable", a);
 
   GeneratorImpl& gen = Build();
 
@@ -57,7 +56,7 @@
 
 TEST_F(WgslGeneratorImplTest, EmitType_RuntimeArray) {
   auto* a = ty.array(ty.bool_(), 0);
-  AST().AddConstructedType(ty.alias("make_type_reachable", a));
+  Alias("make_type_reachable", a);
 
   GeneratorImpl& gen = Build();
 
@@ -67,7 +66,7 @@
 
 TEST_F(WgslGeneratorImplTest, EmitType_Bool) {
   auto* bool_ = ty.bool_();
-  AST().AddConstructedType(ty.alias("make_type_reachable", bool_));
+  Alias("make_type_reachable", bool_);
 
   GeneratorImpl& gen = Build();
 
@@ -77,7 +76,7 @@
 
 TEST_F(WgslGeneratorImplTest, EmitType_F32) {
   auto* f32 = ty.f32();
-  AST().AddConstructedType(ty.alias("make_type_reachable", f32));
+  Alias("make_type_reachable", f32);
 
   GeneratorImpl& gen = Build();
 
@@ -87,7 +86,7 @@
 
 TEST_F(WgslGeneratorImplTest, EmitType_I32) {
   auto* i32 = ty.i32();
-  AST().AddConstructedType(ty.alias("make_type_reachable", i32));
+  Alias("make_type_reachable", i32);
 
   GeneratorImpl& gen = Build();
 
@@ -97,7 +96,7 @@
 
 TEST_F(WgslGeneratorImplTest, EmitType_Matrix) {
   auto* mat2x3 = ty.mat2x3<f32>();
-  AST().AddConstructedType(ty.alias("make_type_reachable", mat2x3));
+  Alias("make_type_reachable", mat2x3);
 
   GeneratorImpl& gen = Build();
 
@@ -107,7 +106,7 @@
 
 TEST_F(WgslGeneratorImplTest, EmitType_Pointer) {
   auto* p = ty.pointer<f32>(ast::StorageClass::kWorkgroup);
-  AST().AddConstructedType(ty.alias("make_type_reachable", p));
+  Alias("make_type_reachable", p);
 
   GeneratorImpl& gen = Build();
 
@@ -250,7 +249,7 @@
 
 TEST_F(WgslGeneratorImplTest, EmitType_U32) {
   auto* u32 = ty.u32();
-  AST().AddConstructedType(ty.alias("make_type_reachable", u32));
+  Alias("make_type_reachable", u32);
 
   GeneratorImpl& gen = Build();
 
@@ -260,7 +259,7 @@
 
 TEST_F(WgslGeneratorImplTest, EmitType_Vector) {
   auto* vec3 = ty.vec3<f32>();
-  AST().AddConstructedType(ty.alias("make_type_reachable", vec3));
+  Alias("make_type_reachable", vec3);
 
   GeneratorImpl& gen = Build();
 
@@ -282,7 +281,7 @@
   auto param = GetParam();
 
   auto* d = ty.depth_texture(param.dim);
-  AST().AddConstructedType(ty.alias("make_type_reachable", d));
+  Alias("make_type_reachable", d);
 
   GeneratorImpl& gen = Build();
 
@@ -304,7 +303,7 @@
   auto param = GetParam();
 
   auto* t = ty.sampled_texture(param.dim, ty.f32());
-  AST().AddConstructedType(ty.alias("make_type_reachable", t));
+  Alias("make_type_reachable", t);
 
   GeneratorImpl& gen = Build();
 
@@ -316,7 +315,7 @@
   auto param = GetParam();
 
   auto* t = ty.sampled_texture(param.dim, ty.i32());
-  AST().AddConstructedType(ty.alias("make_type_reachable", t));
+  Alias("make_type_reachable", t);
 
   GeneratorImpl& gen = Build();
 
@@ -328,7 +327,7 @@
   auto param = GetParam();
 
   auto* t = ty.sampled_texture(param.dim, ty.u32());
-  AST().AddConstructedType(ty.alias("make_type_reachable", t));
+  Alias("make_type_reachable", t);
 
   GeneratorImpl& gen = Build();
 
@@ -351,7 +350,7 @@
   auto param = GetParam();
 
   auto* t = ty.multisampled_texture(param.dim, ty.f32());
-  AST().AddConstructedType(ty.alias("make_type_reachable", t));
+  Alias("make_type_reachable", t);
 
   GeneratorImpl& gen = Build();
 
@@ -363,7 +362,7 @@
   auto param = GetParam();
 
   auto* t = ty.multisampled_texture(param.dim, ty.i32());
-  AST().AddConstructedType(ty.alias("make_type_reachable", t));
+  Alias("make_type_reachable", t);
 
   GeneratorImpl& gen = Build();
 
@@ -375,7 +374,7 @@
   auto param = GetParam();
 
   auto* t = ty.multisampled_texture(param.dim, ty.u32());
-  AST().AddConstructedType(ty.alias("make_type_reachable", t));
+  Alias("make_type_reachable", t);
 
   GeneratorImpl& gen = Build();
 
@@ -503,7 +502,7 @@
 
 TEST_F(WgslGeneratorImplTest, EmitType_Sampler) {
   auto* sampler = ty.sampler(ast::SamplerKind::kSampler);
-  AST().AddConstructedType(ty.alias("make_type_reachable", sampler));
+  Alias("make_type_reachable", sampler);
 
   GeneratorImpl& gen = Build();
 
@@ -513,7 +512,7 @@
 
 TEST_F(WgslGeneratorImplTest, EmitType_SamplerComparison) {
   auto* sampler = ty.sampler(ast::SamplerKind::kComparisonSampler);
-  AST().AddConstructedType(ty.alias("make_type_reachable", sampler));
+  Alias("make_type_reachable", sampler);
 
   GeneratorImpl& gen = Build();