src/tint/lang/wgsl/resolver/variable_validation_test.cc - dawn - Git at Google

 // Copyright 2021 The Dawn & Tint Authors
 //
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are met:
 //
 // 1. Redistributions of source code must retain the above copyright notice, this
 //    list of conditions and the following disclaimer.
 //
 // 2. Redistributions in binary form must reproduce the above copyright notice,
 //    this list of conditions and the following disclaimer in the documentation
 //    and/or other materials provided with the distribution.
 //
 // 3. Neither the name of the copyright holder nor the names of its
 //    contributors may be used to endorse or promote products derived from
 //    this software without specific prior written permission.
 //
 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 // AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 // IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 // DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
 // FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 // DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
 // SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
 // CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 // OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

 #include "gmock/gmock.h"
 #include "src/tint/lang/core/type/texture_dimension.h"
 #include "src/tint/lang/wgsl/resolver/resolver.h"
 #include "src/tint/lang/wgsl/resolver/resolver_helper_test.h"

 namespace tint::resolver {
 namespace {

 using namespace tint::core::fluent_types;     // NOLINT
 using namespace tint::core::number_suffixes;  // NOLINT

 struct ResolverVariableValidationTest : public resolver::TestHelper, public testing::Test {};

 TEST_F(ResolverVariableValidationTest, VarNoInitializerNoType) {
     // var a;
     WrapInFunction(Var(Source{{12, 34}}, "a"));

     EXPECT_FALSE(r()->Resolve());
     EXPECT_EQ(r()->error(), "12:34 error: var declaration requires a type or initializer");
 }

 TEST_F(ResolverVariableValidationTest, GlobalVarNoInitializerNoType) {
     // var a;
     GlobalVar(Source{{12, 34}}, "a");

     EXPECT_FALSE(r()->Resolve());
     EXPECT_EQ(r()->error(), "12:34 error: var declaration requires a type or initializer");
 }

 TEST_F(ResolverVariableValidationTest, VarInitializerNoReturnValueBuiltin) {
     // fn f() { var a = storageBarrier(); }
     auto* NoReturnValueBuiltin = Call(Source{{12, 34}}, "storageBarrier");
     WrapInFunction(Var("a", NoReturnValueBuiltin));

     EXPECT_FALSE(r()->Resolve());
     EXPECT_EQ(r()->error(),
               "12:34 error: builtin function 'storageBarrier' does not return a value");
 }

 TEST_F(ResolverVariableValidationTest, GlobalVarInitializerNoReturnValueBuiltin) {
     // var a = storageBarrier();
     auto* NoReturnValueBuiltin = Call(Source{{12, 34}}, "storageBarrier");
     GlobalVar("a", NoReturnValueBuiltin);

     EXPECT_FALSE(r()->Resolve());
     EXPECT_EQ(r()->error(),
               "12:34 error: builtin function 'storageBarrier' does not return a value");
 }

 TEST_F(ResolverVariableValidationTest, GlobalVarNoAddressSpace) {
     // var a : i32;
     GlobalVar(Source{{12, 34}}, "a", ty.i32());

     EXPECT_FALSE(r()->Resolve());
     EXPECT_EQ(
         r()->error(),
         R"(12:34 error: module-scope 'var' declarations that are not of texture or sampler types must provide an address space)");
 }

 TEST_F(ResolverVariableValidationTest, GlobalVarWithInitializerNoAddressSpace) {
     // var a = 1;
     GlobalVar(Source{{12, 34}}, "a", Expr(1_a));

     EXPECT_FALSE(r()->Resolve());
     EXPECT_EQ(
         r()->error(),
         R"(12:34 error: module-scope 'var' declarations that are not of texture or sampler types must provide an address space)");
 }

 TEST_F(ResolverVariableValidationTest, GlobalVarUsedAtModuleScope) {
     // var<private> a : i32;
     // var<private> b : i32 = a;
     GlobalVar(Source{{12, 34}}, "a", ty.i32(), core::AddressSpace::kPrivate);
     GlobalVar("b", ty.i32(), core::AddressSpace::kPrivate, Expr(Source{{56, 78}}, "a"));

     EXPECT_FALSE(r()->Resolve());
     EXPECT_EQ(r()->error(), R"(56:78 error: 'var a' cannot be referenced at module-scope
 12:34 note: 'var a' declared here)");
 }

 TEST_F(ResolverVariableValidationTest, OverrideNoInitializerNoType) {
     // override a;
     Override(Source{{12, 34}}, "a");

     EXPECT_FALSE(r()->Resolve());
     EXPECT_EQ(r()->error(), "12:34 error: override declaration requires a type or initializer");
 }

 TEST_F(ResolverVariableValidationTest, OverrideExceedsIDLimit_LastUnreserved) {
     // override o0 : i32;
     // override o1 : i32;
     // ...
     // override bang : i32;
     constexpr size_t kLimit = std::numeric_limits<decltype(OverrideId::value)>::max();
     for (size_t i = 0; i <= kLimit; i++) {
         Override("o" + std::to_string(i), ty.i32());
     }
     Override(Source{{12, 34}}, "bang", ty.i32());

     EXPECT_FALSE(r()->Resolve());
     EXPECT_EQ(r()->error(), "12:34 error: number of 'override' variables exceeded limit of 65535");
 }

 TEST_F(ResolverVariableValidationTest, OverrideExceedsIDLimit_LastReserved) {
     // override o0 : i32;
     // override o1 : i32;
     // ...
     // @id(N) override oN : i32;
     constexpr size_t kLimit = std::numeric_limits<decltype(OverrideId::value)>::max();
     Override("reserved", ty.i32(), Id(AInt(kLimit)));
     for (size_t i = 0; i < kLimit; i++) {
         Override("o" + std::to_string(i), ty.i32());
     }
     Override(Source{{12, 34}}, "bang", ty.i32());

     EXPECT_FALSE(r()->Resolve());
     EXPECT_EQ(r()->error(), "12:34 error: number of 'override' variables exceeded limit of 65535");
 }

 TEST_F(ResolverVariableValidationTest, VarTypeNotConstructible) {
     // var i : i32;
     // var p : pointer<function, i32> = &v;
     auto* i = Var("i", ty.i32());
     auto* p = Var("a", ty.ptr<function, i32>(Source{{56, 78}}), core::AddressSpace::kUndefined,
                   AddressOf(Source{{12, 34}}, "i"));
     WrapInFunction(i, p);

     EXPECT_FALSE(r()->Resolve());
     EXPECT_EQ(r()->error(), "56:78 error: function-scope 'var' must have a constructible type");
 }

 TEST_F(ResolverVariableValidationTest, LetTypeNotConstructible) {
     // @group(0) @binding(0) var t1 : texture_2d<f32>;
     // let t2 : t1;
     auto* t1 = GlobalVar("t1", ty.sampled_texture(core::type::TextureDimension::k2d, ty.f32()),
                          Group(0_a), Binding(0_a));
     auto* t2 = Let(Source{{56, 78}}, "t2", Expr(t1));
     WrapInFunction(t2);

     EXPECT_FALSE(r()->Resolve());
     EXPECT_EQ(r()->error(), "56:78 error: texture_2d<f32> cannot be used as the type of a 'let'");
 }

 TEST_F(ResolverVariableValidationTest, OverrideExplicitTypeNotScalar) {
     // override o : vec3<f32>;
     Override(Source{{56, 78}}, "o", ty.vec3<f32>());

     EXPECT_FALSE(r()->Resolve());
     EXPECT_EQ(r()->error(), "56:78 error: vec3<f32> cannot be used as the type of a 'override'");
 }

 TEST_F(ResolverVariableValidationTest, OverrideInferedTypeNotScalar) {
     // override o = vec3(1.0f);
     Override(Source{{56, 78}}, "o", Call<vec3<f32>>(1.0_f));

     EXPECT_FALSE(r()->Resolve());
     EXPECT_EQ(r()->error(), "56:78 error: vec3<f32> cannot be used as the type of a 'override'");
 }

 TEST_F(ResolverVariableValidationTest, ConstInitializerWrongType) {
     // const c : i32 = 2u
     WrapInFunction(Const(Source{{3, 3}}, "c", ty.i32(), Expr(2_u)));

     EXPECT_FALSE(r()->Resolve());
     EXPECT_EQ(r()->error(),
               R"(3:3 error: cannot initialize 'const' of type 'i32' with value of type 'u32')");
 }

 TEST_F(ResolverVariableValidationTest, LetInitializerWrongType) {
     // var v : i32 = 2u
     WrapInFunction(Let(Source{{3, 3}}, "v", ty.i32(), Expr(2_u)));

     EXPECT_FALSE(r()->Resolve());
     EXPECT_EQ(r()->error(),
               R"(3:3 error: cannot initialize 'let' of type 'i32' with value of type 'u32')");
 }

 TEST_F(ResolverVariableValidationTest, VarInitializerWrongType) {
     // var v : i32 = 2u
     WrapInFunction(Var(Source{{3, 3}}, "v", ty.i32(), Expr(2_u)));

     EXPECT_FALSE(r()->Resolve());
     EXPECT_EQ(r()->error(),
               R"(3:3 error: cannot initialize 'var' of type 'i32' with value of type 'u32')");
 }

 TEST_F(ResolverVariableValidationTest, ConstInitializerWrongTypeViaAlias) {
     auto* a = Alias("I32", ty.i32());
     WrapInFunction(Const(Source{{3, 3}}, "v", ty.Of(a), Expr(2_u)));

     EXPECT_FALSE(r()->Resolve());
     EXPECT_EQ(r()->error(),
               R"(3:3 error: cannot initialize 'const' of type 'i32' with value of type 'u32')");
 }

 TEST_F(ResolverVariableValidationTest, LetInitializerWrongTypeViaAlias) {
     auto* a = Alias("I32", ty.i32());
     WrapInFunction(Let(Source{{3, 3}}, "v", ty.Of(a), Expr(2_u)));

     EXPECT_FALSE(r()->Resolve());
     EXPECT_EQ(r()->error(),
               R"(3:3 error: cannot initialize 'let' of type 'i32' with value of type 'u32')");
 }

 TEST_F(ResolverVariableValidationTest, VarInitializerWrongTypeViaAlias) {
     auto* a = Alias("I32", ty.i32());
     WrapInFunction(Var(Source{{3, 3}}, "v", ty.Of(a), Expr(2_u)));

     EXPECT_FALSE(r()->Resolve());
     EXPECT_EQ(r()->error(),
               R"(3:3 error: cannot initialize 'var' of type 'i32' with value of type 'u32')");
 }

 TEST_F(ResolverVariableValidationTest, LetOfPtrConstructedWithRef) {
     // var a : f32;
     // let b : ptr<function,f32> = a;
     const auto priv = core::AddressSpace::kFunction;
     auto* var_a = Var("a", ty.f32(), priv);
     auto* var_b = Let(Source{{12, 34}}, "b", ty.ptr<f32>(priv), Expr("a"));
     WrapInFunction(var_a, var_b);

     ASSERT_FALSE(r()->Resolve());

     EXPECT_EQ(
         r()->error(),
         R"(12:34 error: cannot initialize 'let' of type 'ptr<function, f32, read_write>' with value of type 'f32')");
 }

 TEST_F(ResolverVariableValidationTest, LocalLetRedeclared) {
     // let l : f32 = 1.;
     // let l : i32 = 0;
     auto* l1 = Let("l", ty.f32(), Expr(1_f));
     auto* l2 = Let(Source{{12, 34}}, "l", ty.i32(), Expr(0_i));
     WrapInFunction(l1, l2);

     EXPECT_FALSE(r()->Resolve());
     EXPECT_EQ(r()->error(),
               "12:34 error: redeclaration of 'l'\nnote: 'l' previously declared here");
 }

 TEST_F(ResolverVariableValidationTest, GlobalVarRedeclaredAsLocal) {
     // var v : f32 = 2.1;
     // fn my_func() {
     //   var v : f32 = 2.0;
     //   return 0;
     // }

     GlobalVar("v", ty.f32(), core::AddressSpace::kPrivate, Expr(2.1_f));

     WrapInFunction(Var(Source{{12, 34}}, "v", ty.f32(), Expr(2_f)));

     EXPECT_TRUE(r()->Resolve()) << r()->error();
 }

 TEST_F(ResolverVariableValidationTest, VarRedeclaredInInnerBlock) {
     // {
     //  var v : f32;
     //  { var v : f32; }
     // }
     auto* var_outer = Var("v", ty.f32());
     auto* var_inner = Var(Source{{12, 34}}, "v", ty.f32());
     auto* inner = Block(Decl(var_inner));
     auto* outer_body = Block(Decl(var_outer), inner);

     WrapInFunction(outer_body);

     EXPECT_TRUE(r()->Resolve()) << r()->error();
 }

 TEST_F(ResolverVariableValidationTest, VarRedeclaredInIfBlock) {
     // {
     //   var v : f32 = 3.14;
     //   if (true) { var v : f32 = 2.0; }
     // }
     auto* var_a_float = Var("v", ty.f32(), Expr(3.1_f));

     auto* var = Var(Source{{12, 34}}, "v", ty.f32(), Expr(2_f));

     auto* cond = Expr(true);
     auto* body = Block(Decl(var));

     auto* outer_body = Block(Decl(var_a_float), If(cond, body));

     WrapInFunction(outer_body);

     EXPECT_TRUE(r()->Resolve()) << r()->error();
 }

 TEST_F(ResolverVariableValidationTest, InferredPtrStorageAccessMismatch) {
     // struct Inner {
     //    arr: array<i32, 4>;
     // }
     // struct S {
     //    inner: Inner;
     // }
     // @group(0) @binding(0) var<storage> s : S;
     // fn f() {
     //   let p : pointer<storage, i32, read_write> = &s.inner.arr[2i];
     // }
     auto* inner = Structure("Inner", Vector{
                                          Member("arr", ty.array<i32, 4>()),
                                      });
     auto* buf = Structure("S", Vector{
                                    Member("inner", ty.Of(inner)),
                                });
     auto* var = GlobalVar("s", ty.Of(buf), core::AddressSpace::kStorage, Binding(0_a), Group(0_a));

     auto* expr = IndexAccessor(MemberAccessor(MemberAccessor(var, "inner"), "arr"), 2_i);
     auto* ptr = Let(Source{{12, 34}}, "p", ty.ptr<storage, i32, read_write>(), AddressOf(expr));

     WrapInFunction(ptr);

     EXPECT_FALSE(r()->Resolve());
     EXPECT_EQ(
         r()->error(),
         R"(12:34 error: cannot initialize 'let' of type 'ptr<storage, i32, read_write>' with value of type 'ptr<storage, i32, read>')");
 }

 TEST_F(ResolverVariableValidationTest, NonConstructibleType_Atomic) {
     auto* v = Var("v", ty.atomic(Source{{12, 34}}, ty.i32()));
     WrapInFunction(v);

     EXPECT_FALSE(r()->Resolve());
     EXPECT_EQ(r()->error(), "12:34 error: function-scope 'var' must have a constructible type");
 }

 TEST_F(ResolverVariableValidationTest, NonConstructibleType_RuntimeArray) {
     auto* s = Structure("S", Vector{
                                  Member(Source{{12, 34}}, "m", ty.array<i32>()),
                              });
     auto* v = Var(Source{{56, 78}}, "v", ty.Of(s));
     WrapInFunction(v);

     EXPECT_FALSE(r()->Resolve());
     EXPECT_EQ(r()->error(),
               R"(error: runtime-sized arrays can only be used in the <storage> address space
 12:34 note: while analyzing structure member S.m
 56:78 note: while instantiating 'var' v)");
 }

 TEST_F(ResolverVariableValidationTest, NonConstructibleType_Struct_WithAtomic) {
     auto* s = Structure("S", Vector{
                                  Member("m", ty.atomic(ty.i32())),
                              });
     auto* v = Var("v", ty.Of(s));
     WrapInFunction(v);

     EXPECT_FALSE(r()->Resolve());
     EXPECT_EQ(r()->error(), "error: function-scope 'var' must have a constructible type");
 }

 TEST_F(ResolverVariableValidationTest, NonConstructibleType_InferredType) {
     // @group(0) @binding(0) var s : sampler;
     // fn foo() {
     //   var v = s;
     // }
     GlobalVar("s", ty.sampler(core::type::SamplerKind::kSampler), Group(0_a), Binding(0_a));
     auto* v = Var(Source{{12, 34}}, "v", Expr("s"));
     WrapInFunction(v);

     EXPECT_FALSE(r()->Resolve());
     EXPECT_EQ(r()->error(), "12:34 error: function-scope 'var' must have a constructible type");
 }

 TEST_F(ResolverVariableValidationTest, InvalidAddressSpaceForInitializer) {
     // var<workgroup> v : f32 = 1.23;
     GlobalVar(Source{{12, 34}}, "v", ty.f32(), core::AddressSpace::kWorkgroup, Expr(1.23_f));

     EXPECT_FALSE(r()->Resolve());
     EXPECT_EQ(r()->error(),
               "12:34 error: var of address space 'workgroup' cannot have "
               "an initializer. var initializers are only supported for the "
               "address spaces 'private' and 'function'");
 }

 TEST_F(ResolverVariableValidationTest, VectorConstNoType) {
     // const a vec3 = vec3<f32>();
     WrapInFunction(Const("a", ty.vec3<Infer>(Source{{12, 34}}), Call<vec3<f32>>()));

     EXPECT_FALSE(r()->Resolve());
     EXPECT_EQ(r()->error(), "12:34 error: expected '<' for 'vec3'");
 }

 TEST_F(ResolverVariableValidationTest, VectorLetNoType) {
     // let a : vec3 = vec3<f32>();
     WrapInFunction(Let("a", ty.vec3<Infer>(Source{{12, 34}}), Call<vec3<f32>>()));

     EXPECT_FALSE(r()->Resolve());
     EXPECT_EQ(r()->error(), "12:34 error: expected '<' for 'vec3'");
 }

 TEST_F(ResolverVariableValidationTest, VectorVarNoType) {
     // var a : vec3;
     WrapInFunction(Var("a", ty.vec3<Infer>(Source{{12, 34}})));

     EXPECT_FALSE(r()->Resolve());
     EXPECT_EQ(r()->error(), "12:34 error: expected '<' for 'vec3'");
 }

 TEST_F(ResolverVariableValidationTest, MatrixConstNoType) {
     // const a : mat3x3 = mat3x3<f32>();
     WrapInFunction(Const("a", ty.mat3x3<Infer>(Source{{12, 34}}), Call<mat3x3<f32>>()));

     EXPECT_FALSE(r()->Resolve());
     EXPECT_EQ(r()->error(), "12:34 error: expected '<' for 'mat3x3'");
 }

 TEST_F(ResolverVariableValidationTest, MatrixLetNoType) {
     // let a : mat3x3 = mat3x3<f32>();
     WrapInFunction(Let("a", ty.mat3x3<Infer>(Source{{12, 34}}), Call<mat3x3<f32>>()));

     EXPECT_FALSE(r()->Resolve());
     EXPECT_EQ(r()->error(), "12:34 error: expected '<' for 'mat3x3'");
 }

 TEST_F(ResolverVariableValidationTest, MatrixVarNoType) {
     // var a : mat3x3;
     WrapInFunction(Var("a", ty.mat3x3<Infer>(Source{{12, 34}})));

     EXPECT_FALSE(r()->Resolve());
     EXPECT_EQ(r()->error(), "12:34 error: expected '<' for 'mat3x3'");
 }

 TEST_F(ResolverVariableValidationTest, GlobalConstWithRuntimeExpression) {
     GlobalConst("c", Call(Source{{12, 34}}, "dpdx", 1._a));

     EXPECT_FALSE(r()->Resolve());
     EXPECT_EQ(
         r()->error(),
         R"(12:34 error: const initializer requires a const-expression, but expression is a runtime-expression)");
 }

 TEST_F(ResolverVariableValidationTest, ConstInitWithVar) {
     auto* v = Var("v", Expr(1_i));
     auto* c = Const("c", Expr(Source{{12, 34}}, v));
     WrapInFunction(v, Decl(Source{{56, 78}}, c));

     EXPECT_FALSE(r()->Resolve());
     EXPECT_EQ(
         r()->error(),
         R"(12:34 error: const initializer requires a const-expression, but expression is a runtime-expression
 56:78 note: consider changing 'const' to 'let')");
 }

 TEST_F(ResolverVariableValidationTest, ConstInitWithOverride) {
     auto* o = Override("v", Expr(1_i));
     auto* c = Const("c", Expr(Source{{12, 34}}, o));
     WrapInFunction(Decl(Source{{56, 78}}, c));

     EXPECT_FALSE(r()->Resolve());
     EXPECT_EQ(
         r()->error(),
         R"(12:34 error: const initializer requires a const-expression, but expression is an override-expression
 56:78 note: consider changing 'const' to 'let')");
 }

 TEST_F(ResolverVariableValidationTest, ConstInitWithLet) {
     auto* l = Let("v", Expr(1_i));
     auto* c = Const("c", Expr(Source{{12, 34}}, l));
     WrapInFunction(l, Decl(Source{{56, 78}}, c));

     EXPECT_FALSE(r()->Resolve());
     EXPECT_EQ(
         r()->error(),
         R"(12:34 error: const initializer requires a const-expression, but expression is a runtime-expression
 56:78 note: consider changing 'const' to 'let')");
 }

 TEST_F(ResolverVariableValidationTest, ConstInitWithRuntimeExpr) {
     // const c = clamp(2, dpdx(0.5), 3);
     auto* c = Const("c", Call("clamp", 2_a, Call(Source{{12, 34}}, "dpdx", 0.5_a), 3_a));
     WrapInFunction(Decl(Source{{56, 78}}, c));

     EXPECT_FALSE(r()->Resolve());
     EXPECT_EQ(
         r()->error(),
         R"(12:34 error: const initializer requires a const-expression, but expression is a runtime-expression
 56:78 note: consider changing 'const' to 'let')");
 }

 TEST_F(ResolverVariableValidationTest, ConstInitWithOverrideExpr) {
     auto* o = Override("v", Expr(1_i));
     auto* c = Const("c", Add(10_a, Expr(Source{{12, 34}}, o)));
     WrapInFunction(Decl(Source{{56, 78}}, c));

     EXPECT_FALSE(r()->Resolve());
     EXPECT_EQ(
         r()->error(),
         R"(12:34 error: const initializer requires a const-expression, but expression is an override-expression
 56:78 note: consider changing 'const' to 'let')");
 }

 TEST_F(ResolverVariableValidationTest, GlobalVariable_PushConstantWithInitializer) {
     // enable chromium_experimental_push_constant;
     // var<push_constant> a : u32 = 0u;
     Enable(wgsl::Extension::kChromiumExperimentalPushConstant);
     GlobalVar(Source{{1u, 2u}}, "a", ty.u32(), core::AddressSpace::kPushConstant,
               Expr(Source{{3u, 4u}}, u32(0)));

     ASSERT_FALSE(r()->Resolve());
     EXPECT_EQ(
         r()->error(),
         R"(1:2 error: var of address space 'push_constant' cannot have an initializer. var initializers are only supported for the address spaces 'private' and 'function')");
 }

 }  // namespace
 }  // namespace tint::resolver
	// Copyright 2021 The Dawn & Tint Authors
	//
	// Redistribution and use in source and binary forms, with or without
	// modification, are permitted provided that the following conditions are met:
	//
	// 1. Redistributions of source code must retain the above copyright notice, this
	// list of conditions and the following disclaimer.
	//
	// 2. Redistributions in binary form must reproduce the above copyright notice,
	// this list of conditions and the following disclaimer in the documentation
	// and/or other materials provided with the distribution.
	//
	// 3. Neither the name of the copyright holder nor the names of its
	// contributors may be used to endorse or promote products derived from
	// this software without specific prior written permission.
	//
	// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
	// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
	// DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
	// FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
	// DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
	// SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
	// CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
	// OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
	// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

	#include "gmock/gmock.h"
	#include "src/tint/lang/core/type/texture_dimension.h"
	#include "src/tint/lang/wgsl/resolver/resolver.h"
	#include "src/tint/lang/wgsl/resolver/resolver_helper_test.h"

	namespace tint::resolver {
	namespace {

	using namespace tint::core::fluent_types; // NOLINT
	using namespace tint::core::number_suffixes; // NOLINT

	struct ResolverVariableValidationTest : public resolver::TestHelper, public testing::Test {};

	TEST_F(ResolverVariableValidationTest, VarNoInitializerNoType) {
	// var a;
	WrapInFunction(Var(Source{{12, 34}}, "a"));

	EXPECT_FALSE(r()->Resolve());
	EXPECT_EQ(r()->error(), "12:34 error: var declaration requires a type or initializer");
	}

	TEST_F(ResolverVariableValidationTest, GlobalVarNoInitializerNoType) {
	// var a;
	GlobalVar(Source{{12, 34}}, "a");

	EXPECT_FALSE(r()->Resolve());
	EXPECT_EQ(r()->error(), "12:34 error: var declaration requires a type or initializer");
	}

	TEST_F(ResolverVariableValidationTest, VarInitializerNoReturnValueBuiltin) {
	// fn f() { var a = storageBarrier(); }
	auto* NoReturnValueBuiltin = Call(Source{{12, 34}}, "storageBarrier");
	WrapInFunction(Var("a", NoReturnValueBuiltin));

	EXPECT_FALSE(r()->Resolve());
	EXPECT_EQ(r()->error(),
	"12:34 error: builtin function 'storageBarrier' does not return a value");
	}

	TEST_F(ResolverVariableValidationTest, GlobalVarInitializerNoReturnValueBuiltin) {
	// var a = storageBarrier();
	auto* NoReturnValueBuiltin = Call(Source{{12, 34}}, "storageBarrier");
	GlobalVar("a", NoReturnValueBuiltin);

	EXPECT_FALSE(r()->Resolve());
	EXPECT_EQ(r()->error(),
	"12:34 error: builtin function 'storageBarrier' does not return a value");
	}

	TEST_F(ResolverVariableValidationTest, GlobalVarNoAddressSpace) {
	// var a : i32;
	GlobalVar(Source{{12, 34}}, "a", ty.i32());

	EXPECT_FALSE(r()->Resolve());
	EXPECT_EQ(
	r()->error(),
	R"(12:34 error: module-scope 'var' declarations that are not of texture or sampler types must provide an address space)");
	}

	TEST_F(ResolverVariableValidationTest, GlobalVarWithInitializerNoAddressSpace) {
	// var a = 1;
	GlobalVar(Source{{12, 34}}, "a", Expr(1_a));

	EXPECT_FALSE(r()->Resolve());
	EXPECT_EQ(
	r()->error(),
	R"(12:34 error: module-scope 'var' declarations that are not of texture or sampler types must provide an address space)");
	}

	TEST_F(ResolverVariableValidationTest, GlobalVarUsedAtModuleScope) {
	// var<private> a : i32;
	// var<private> b : i32 = a;
	GlobalVar(Source{{12, 34}}, "a", ty.i32(), core::AddressSpace::kPrivate);
	GlobalVar("b", ty.i32(), core::AddressSpace::kPrivate, Expr(Source{{56, 78}}, "a"));

	EXPECT_FALSE(r()->Resolve());
	EXPECT_EQ(r()->error(), R"(56:78 error: 'var a' cannot be referenced at module-scope
	12:34 note: 'var a' declared here)");
	}

	TEST_F(ResolverVariableValidationTest, OverrideNoInitializerNoType) {
	// override a;
	Override(Source{{12, 34}}, "a");

	EXPECT_FALSE(r()->Resolve());
	EXPECT_EQ(r()->error(), "12:34 error: override declaration requires a type or initializer");
	}

	TEST_F(ResolverVariableValidationTest, OverrideExceedsIDLimit_LastUnreserved) {
	// override o0 : i32;
	// override o1 : i32;
	// ...
	// override bang : i32;
	constexpr size_t kLimit = std::numeric_limits<decltype(OverrideId::value)>::max();
	for (size_t i = 0; i <= kLimit; i++) {
	Override("o" + std::to_string(i), ty.i32());
	}
	Override(Source{{12, 34}}, "bang", ty.i32());

	EXPECT_FALSE(r()->Resolve());
	EXPECT_EQ(r()->error(), "12:34 error: number of 'override' variables exceeded limit of 65535");
	}

	TEST_F(ResolverVariableValidationTest, OverrideExceedsIDLimit_LastReserved) {
	// override o0 : i32;
	// override o1 : i32;
	// ...
	// @id(N) override oN : i32;
	constexpr size_t kLimit = std::numeric_limits<decltype(OverrideId::value)>::max();
	Override("reserved", ty.i32(), Id(AInt(kLimit)));
	for (size_t i = 0; i < kLimit; i++) {
	Override("o" + std::to_string(i), ty.i32());
	}
	Override(Source{{12, 34}}, "bang", ty.i32());

	EXPECT_FALSE(r()->Resolve());
	EXPECT_EQ(r()->error(), "12:34 error: number of 'override' variables exceeded limit of 65535");
	}

	TEST_F(ResolverVariableValidationTest, VarTypeNotConstructible) {
	// var i : i32;
	// var p : pointer<function, i32> = &v;
	auto* i = Var("i", ty.i32());
	auto* p = Var("a", ty.ptr<function, i32>(Source{{56, 78}}), core::AddressSpace::kUndefined,
	AddressOf(Source{{12, 34}}, "i"));
	WrapInFunction(i, p);

	EXPECT_FALSE(r()->Resolve());
	EXPECT_EQ(r()->error(), "56:78 error: function-scope 'var' must have a constructible type");
	}

	TEST_F(ResolverVariableValidationTest, LetTypeNotConstructible) {
	// @group(0) @binding(0) var t1 : texture_2d<f32>;
	// let t2 : t1;
	auto* t1 = GlobalVar("t1", ty.sampled_texture(core::type::TextureDimension::k2d, ty.f32()),
	Group(0_a), Binding(0_a));
	auto* t2 = Let(Source{{56, 78}}, "t2", Expr(t1));
	WrapInFunction(t2);

	EXPECT_FALSE(r()->Resolve());
	EXPECT_EQ(r()->error(), "56:78 error: texture_2d<f32> cannot be used as the type of a 'let'");
	}

	TEST_F(ResolverVariableValidationTest, OverrideExplicitTypeNotScalar) {
	// override o : vec3<f32>;
	Override(Source{{56, 78}}, "o", ty.vec3<f32>());

	EXPECT_FALSE(r()->Resolve());
	EXPECT_EQ(r()->error(), "56:78 error: vec3<f32> cannot be used as the type of a 'override'");
	}

	TEST_F(ResolverVariableValidationTest, OverrideInferedTypeNotScalar) {
	// override o = vec3(1.0f);
	Override(Source{{56, 78}}, "o", Call<vec3<f32>>(1.0_f));

	EXPECT_FALSE(r()->Resolve());
	EXPECT_EQ(r()->error(), "56:78 error: vec3<f32> cannot be used as the type of a 'override'");
	}

	TEST_F(ResolverVariableValidationTest, ConstInitializerWrongType) {
	// const c : i32 = 2u
	WrapInFunction(Const(Source{{3, 3}}, "c", ty.i32(), Expr(2_u)));

	EXPECT_FALSE(r()->Resolve());
	EXPECT_EQ(r()->error(),
	R"(3:3 error: cannot initialize 'const' of type 'i32' with value of type 'u32')");
	}

	TEST_F(ResolverVariableValidationTest, LetInitializerWrongType) {
	// var v : i32 = 2u
	WrapInFunction(Let(Source{{3, 3}}, "v", ty.i32(), Expr(2_u)));

	EXPECT_FALSE(r()->Resolve());
	EXPECT_EQ(r()->error(),
	R"(3:3 error: cannot initialize 'let' of type 'i32' with value of type 'u32')");
	}

	TEST_F(ResolverVariableValidationTest, VarInitializerWrongType) {
	// var v : i32 = 2u
	WrapInFunction(Var(Source{{3, 3}}, "v", ty.i32(), Expr(2_u)));

	EXPECT_FALSE(r()->Resolve());
	EXPECT_EQ(r()->error(),
	R"(3:3 error: cannot initialize 'var' of type 'i32' with value of type 'u32')");
	}

	TEST_F(ResolverVariableValidationTest, ConstInitializerWrongTypeViaAlias) {
	auto* a = Alias("I32", ty.i32());
	WrapInFunction(Const(Source{{3, 3}}, "v", ty.Of(a), Expr(2_u)));

	EXPECT_FALSE(r()->Resolve());
	EXPECT_EQ(r()->error(),
	R"(3:3 error: cannot initialize 'const' of type 'i32' with value of type 'u32')");
	}

	TEST_F(ResolverVariableValidationTest, LetInitializerWrongTypeViaAlias) {
	auto* a = Alias("I32", ty.i32());
	WrapInFunction(Let(Source{{3, 3}}, "v", ty.Of(a), Expr(2_u)));

	EXPECT_FALSE(r()->Resolve());
	EXPECT_EQ(r()->error(),
	R"(3:3 error: cannot initialize 'let' of type 'i32' with value of type 'u32')");
	}

	TEST_F(ResolverVariableValidationTest, VarInitializerWrongTypeViaAlias) {
	auto* a = Alias("I32", ty.i32());
	WrapInFunction(Var(Source{{3, 3}}, "v", ty.Of(a), Expr(2_u)));

	EXPECT_FALSE(r()->Resolve());
	EXPECT_EQ(r()->error(),
	R"(3:3 error: cannot initialize 'var' of type 'i32' with value of type 'u32')");
	}

	TEST_F(ResolverVariableValidationTest, LetOfPtrConstructedWithRef) {
	// var a : f32;
	// let b : ptr<function,f32> = a;
	const auto priv = core::AddressSpace::kFunction;
	auto* var_a = Var("a", ty.f32(), priv);
	auto* var_b = Let(Source{{12, 34}}, "b", ty.ptr<f32>(priv), Expr("a"));
	WrapInFunction(var_a, var_b);

	ASSERT_FALSE(r()->Resolve());

	EXPECT_EQ(
	r()->error(),
	R"(12:34 error: cannot initialize 'let' of type 'ptr<function, f32, read_write>' with value of type 'f32')");
	}

	TEST_F(ResolverVariableValidationTest, LocalLetRedeclared) {
	// let l : f32 = 1.;
	// let l : i32 = 0;
	auto* l1 = Let("l", ty.f32(), Expr(1_f));
	auto* l2 = Let(Source{{12, 34}}, "l", ty.i32(), Expr(0_i));
	WrapInFunction(l1, l2);

	EXPECT_FALSE(r()->Resolve());
	EXPECT_EQ(r()->error(),
	"12:34 error: redeclaration of 'l'\nnote: 'l' previously declared here");
	}

	TEST_F(ResolverVariableValidationTest, GlobalVarRedeclaredAsLocal) {
	// var v : f32 = 2.1;
	// fn my_func() {
	// var v : f32 = 2.0;
	// return 0;
	// }

	GlobalVar("v", ty.f32(), core::AddressSpace::kPrivate, Expr(2.1_f));

	WrapInFunction(Var(Source{{12, 34}}, "v", ty.f32(), Expr(2_f)));

	EXPECT_TRUE(r()->Resolve()) << r()->error();
	}

	TEST_F(ResolverVariableValidationTest, VarRedeclaredInInnerBlock) {
	// {
	// var v : f32;
	// { var v : f32; }
	// }
	auto* var_outer = Var("v", ty.f32());
	auto* var_inner = Var(Source{{12, 34}}, "v", ty.f32());
	auto* inner = Block(Decl(var_inner));
	auto* outer_body = Block(Decl(var_outer), inner);

	WrapInFunction(outer_body);

	EXPECT_TRUE(r()->Resolve()) << r()->error();
	}

	TEST_F(ResolverVariableValidationTest, VarRedeclaredInIfBlock) {
	// {
	// var v : f32 = 3.14;
	// if (true) { var v : f32 = 2.0; }
	// }
	auto* var_a_float = Var("v", ty.f32(), Expr(3.1_f));

	auto* var = Var(Source{{12, 34}}, "v", ty.f32(), Expr(2_f));

	auto* cond = Expr(true);
	auto* body = Block(Decl(var));

	auto* outer_body = Block(Decl(var_a_float), If(cond, body));

	WrapInFunction(outer_body);

	EXPECT_TRUE(r()->Resolve()) << r()->error();
	}

	TEST_F(ResolverVariableValidationTest, InferredPtrStorageAccessMismatch) {
	// struct Inner {
	// arr: array<i32, 4>;
	// }
	// struct S {
	// inner: Inner;
	// }
	// @group(0) @binding(0) var<storage> s : S;
	// fn f() {
	// let p : pointer<storage, i32, read_write> = &s.inner.arr[2i];
	// }
	auto* inner = Structure("Inner", Vector{
	Member("arr", ty.array<i32, 4>()),
	});
	auto* buf = Structure("S", Vector{
	Member("inner", ty.Of(inner)),
	});
	auto* var = GlobalVar("s", ty.Of(buf), core::AddressSpace::kStorage, Binding(0_a), Group(0_a));

	auto* expr = IndexAccessor(MemberAccessor(MemberAccessor(var, "inner"), "arr"), 2_i);
	auto* ptr = Let(Source{{12, 34}}, "p", ty.ptr<storage, i32, read_write>(), AddressOf(expr));

	WrapInFunction(ptr);

	EXPECT_FALSE(r()->Resolve());
	EXPECT_EQ(
	r()->error(),
	R"(12:34 error: cannot initialize 'let' of type 'ptr<storage, i32, read_write>' with value of type 'ptr<storage, i32, read>')");
	}

	TEST_F(ResolverVariableValidationTest, NonConstructibleType_Atomic) {
	auto* v = Var("v", ty.atomic(Source{{12, 34}}, ty.i32()));
	WrapInFunction(v);

	EXPECT_FALSE(r()->Resolve());
	EXPECT_EQ(r()->error(), "12:34 error: function-scope 'var' must have a constructible type");
	}

	TEST_F(ResolverVariableValidationTest, NonConstructibleType_RuntimeArray) {
	auto* s = Structure("S", Vector{
	Member(Source{{12, 34}}, "m", ty.array<i32>()),
	});
	auto* v = Var(Source{{56, 78}}, "v", ty.Of(s));
	WrapInFunction(v);

	EXPECT_FALSE(r()->Resolve());
	EXPECT_EQ(r()->error(),
	R"(error: runtime-sized arrays can only be used in the <storage> address space
	12:34 note: while analyzing structure member S.m
	56:78 note: while instantiating 'var' v)");
	}

	TEST_F(ResolverVariableValidationTest, NonConstructibleType_Struct_WithAtomic) {
	auto* s = Structure("S", Vector{
	Member("m", ty.atomic(ty.i32())),
	});
	auto* v = Var("v", ty.Of(s));
	WrapInFunction(v);

	EXPECT_FALSE(r()->Resolve());
	EXPECT_EQ(r()->error(), "error: function-scope 'var' must have a constructible type");
	}

	TEST_F(ResolverVariableValidationTest, NonConstructibleType_InferredType) {
	// @group(0) @binding(0) var s : sampler;
	// fn foo() {
	// var v = s;
	// }
	GlobalVar("s", ty.sampler(core::type::SamplerKind::kSampler), Group(0_a), Binding(0_a));
	auto* v = Var(Source{{12, 34}}, "v", Expr("s"));
	WrapInFunction(v);

	EXPECT_FALSE(r()->Resolve());
	EXPECT_EQ(r()->error(), "12:34 error: function-scope 'var' must have a constructible type");
	}

	TEST_F(ResolverVariableValidationTest, InvalidAddressSpaceForInitializer) {
	// var<workgroup> v : f32 = 1.23;
	GlobalVar(Source{{12, 34}}, "v", ty.f32(), core::AddressSpace::kWorkgroup, Expr(1.23_f));

	EXPECT_FALSE(r()->Resolve());
	EXPECT_EQ(r()->error(),
	"12:34 error: var of address space 'workgroup' cannot have "
	"an initializer. var initializers are only supported for the "
	"address spaces 'private' and 'function'");
	}

	TEST_F(ResolverVariableValidationTest, VectorConstNoType) {
	// const a vec3 = vec3<f32>();
	WrapInFunction(Const("a", ty.vec3<Infer>(Source{{12, 34}}), Call<vec3<f32>>()));

	EXPECT_FALSE(r()->Resolve());
	EXPECT_EQ(r()->error(), "12:34 error: expected '<' for 'vec3'");
	}

	TEST_F(ResolverVariableValidationTest, VectorLetNoType) {
	// let a : vec3 = vec3<f32>();
	WrapInFunction(Let("a", ty.vec3<Infer>(Source{{12, 34}}), Call<vec3<f32>>()));

	EXPECT_FALSE(r()->Resolve());
	EXPECT_EQ(r()->error(), "12:34 error: expected '<' for 'vec3'");
	}

	TEST_F(ResolverVariableValidationTest, VectorVarNoType) {
	// var a : vec3;
	WrapInFunction(Var("a", ty.vec3<Infer>(Source{{12, 34}})));

	EXPECT_FALSE(r()->Resolve());
	EXPECT_EQ(r()->error(), "12:34 error: expected '<' for 'vec3'");
	}

	TEST_F(ResolverVariableValidationTest, MatrixConstNoType) {
	// const a : mat3x3 = mat3x3<f32>();
	WrapInFunction(Const("a", ty.mat3x3<Infer>(Source{{12, 34}}), Call<mat3x3<f32>>()));

	EXPECT_FALSE(r()->Resolve());
	EXPECT_EQ(r()->error(), "12:34 error: expected '<' for 'mat3x3'");
	}

	TEST_F(ResolverVariableValidationTest, MatrixLetNoType) {
	// let a : mat3x3 = mat3x3<f32>();
	WrapInFunction(Let("a", ty.mat3x3<Infer>(Source{{12, 34}}), Call<mat3x3<f32>>()));

	EXPECT_FALSE(r()->Resolve());
	EXPECT_EQ(r()->error(), "12:34 error: expected '<' for 'mat3x3'");
	}

	TEST_F(ResolverVariableValidationTest, MatrixVarNoType) {
	// var a : mat3x3;
	WrapInFunction(Var("a", ty.mat3x3<Infer>(Source{{12, 34}})));

	EXPECT_FALSE(r()->Resolve());
	EXPECT_EQ(r()->error(), "12:34 error: expected '<' for 'mat3x3'");
	}

	TEST_F(ResolverVariableValidationTest, GlobalConstWithRuntimeExpression) {
	GlobalConst("c", Call(Source{{12, 34}}, "dpdx", 1._a));

	EXPECT_FALSE(r()->Resolve());
	EXPECT_EQ(
	r()->error(),
	R"(12:34 error: const initializer requires a const-expression, but expression is a runtime-expression)");
	}

	TEST_F(ResolverVariableValidationTest, ConstInitWithVar) {
	auto* v = Var("v", Expr(1_i));
	auto* c = Const("c", Expr(Source{{12, 34}}, v));
	WrapInFunction(v, Decl(Source{{56, 78}}, c));

	EXPECT_FALSE(r()->Resolve());
	EXPECT_EQ(
	r()->error(),
	R"(12:34 error: const initializer requires a const-expression, but expression is a runtime-expression
	56:78 note: consider changing 'const' to 'let')");
	}

	TEST_F(ResolverVariableValidationTest, ConstInitWithOverride) {
	auto* o = Override("v", Expr(1_i));
	auto* c = Const("c", Expr(Source{{12, 34}}, o));
	WrapInFunction(Decl(Source{{56, 78}}, c));

	EXPECT_FALSE(r()->Resolve());
	EXPECT_EQ(
	r()->error(),
	R"(12:34 error: const initializer requires a const-expression, but expression is an override-expression
	56:78 note: consider changing 'const' to 'let')");
	}

	TEST_F(ResolverVariableValidationTest, ConstInitWithLet) {
	auto* l = Let("v", Expr(1_i));
	auto* c = Const("c", Expr(Source{{12, 34}}, l));
	WrapInFunction(l, Decl(Source{{56, 78}}, c));

	EXPECT_FALSE(r()->Resolve());
	EXPECT_EQ(
	r()->error(),
	R"(12:34 error: const initializer requires a const-expression, but expression is a runtime-expression
	56:78 note: consider changing 'const' to 'let')");
	}

	TEST_F(ResolverVariableValidationTest, ConstInitWithRuntimeExpr) {
	// const c = clamp(2, dpdx(0.5), 3);
	auto* c = Const("c", Call("clamp", 2_a, Call(Source{{12, 34}}, "dpdx", 0.5_a), 3_a));
	WrapInFunction(Decl(Source{{56, 78}}, c));

	EXPECT_FALSE(r()->Resolve());
	EXPECT_EQ(
	r()->error(),
	R"(12:34 error: const initializer requires a const-expression, but expression is a runtime-expression
	56:78 note: consider changing 'const' to 'let')");
	}

	TEST_F(ResolverVariableValidationTest, ConstInitWithOverrideExpr) {
	auto* o = Override("v", Expr(1_i));
	auto* c = Const("c", Add(10_a, Expr(Source{{12, 34}}, o)));
	WrapInFunction(Decl(Source{{56, 78}}, c));

	EXPECT_FALSE(r()->Resolve());
	EXPECT_EQ(
	r()->error(),
	R"(12:34 error: const initializer requires a const-expression, but expression is an override-expression
	56:78 note: consider changing 'const' to 'let')");
	}

	TEST_F(ResolverVariableValidationTest, GlobalVariable_PushConstantWithInitializer) {
	// enable chromium_experimental_push_constant;
	// var<push_constant> a : u32 = 0u;
	Enable(wgsl::Extension::kChromiumExperimentalPushConstant);
	GlobalVar(Source{{1u, 2u}}, "a", ty.u32(), core::AddressSpace::kPushConstant,
	Expr(Source{{3u, 4u}}, u32(0)));

	ASSERT_FALSE(r()->Resolve());
	EXPECT_EQ(
	r()->error(),
	R"(1:2 error: var of address space 'push_constant' cannot have an initializer. var initializers are only supported for the address spaces 'private' and 'function')");
	}

	} // namespace
	} // namespace tint::resolver