src/tint/lang/wgsl/reader/parser/function_decl_test.cc - dawn - Git at Google

 // Copyright 2020 The Tint Authors.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
 // You may obtain a copy of the License at
 //
 //     http://www.apache.org/licenses/LICENSE-2.0
 //
 // Unless required by applicable law or agreed to in writing, software
 // distributed under the License is distributed on an "AS IS" BASIS,
 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 // See the License for the specific language governing permissions and
 // limitations under the License.

 #include "src/tint/lang/wgsl/ast/test_helper.h"
 #include "src/tint/lang/wgsl/ast/workgroup_attribute.h"
 #include "src/tint/lang/wgsl/reader/parser/test_helper.h"
 #include "src/tint/utils/text/string.h"

 namespace tint::wgsl::reader {
 namespace {

 TEST_F(WGSLParserTest, FunctionDecl) {
     auto p = parser("fn main(a : i32, b : f32) { return; }");
     auto attrs = p->attribute_list();
     EXPECT_FALSE(p->has_error()) << p->error();
     ASSERT_FALSE(attrs.errored);
     EXPECT_FALSE(attrs.matched);
     auto f = p->function_decl(attrs.value);
     EXPECT_FALSE(p->has_error()) << p->error();
     EXPECT_FALSE(f.errored);
     EXPECT_TRUE(f.matched);
     ASSERT_NE(f.value, nullptr);

     EXPECT_EQ(f->name->symbol, p->builder().Symbols().Get("main"));
     EXPECT_EQ(f->return_type, nullptr);

     ASSERT_EQ(f->params.Length(), 2u);
     EXPECT_EQ(f->params[0]->name->symbol, p->builder().Symbols().Get("a"));
     EXPECT_EQ(f->params[1]->name->symbol, p->builder().Symbols().Get("b"));

     EXPECT_EQ(f->return_type, nullptr);

     auto* body = f->body;
     ASSERT_EQ(body->statements.Length(), 1u);
     EXPECT_TRUE(body->statements[0]->Is<ast::ReturnStatement>());
 }

 TEST_F(WGSLParserTest, FunctionDecl_Unicode) {
     const std::string function_ident =  // "𝗳𝘂𝗻𝗰𝘁𝗶𝗼𝗻"
         "\xf0\x9d\x97\xb3\xf0\x9d\x98\x82\xf0\x9d\x97\xbb\xf0\x9d\x97\xb0\xf0\x9d"
         "\x98\x81\xf0\x9d\x97\xb6\xf0\x9d\x97\xbc\xf0\x9d\x97\xbb";

     const std::string param_a_ident =  // "𝓹𝓪𝓻𝓪𝓶_𝓪"
         "\xf0\x9d\x93\xb9\xf0\x9d\x93\xaa\xf0\x9d\x93\xbb\xf0\x9d\x93\xaa\xf0\x9d"
         "\x93\xb6\x5f\xf0\x9d\x93\xaa";

     const std::string param_b_ident =  // "𝕡𝕒𝕣𝕒𝕞_𝕓"
         "\xf0\x9d\x95\xa1\xf0\x9d\x95\x92\xf0\x9d\x95\xa3\xf0\x9d\x95\x92\xf0\x9d"
         "\x95\x9e\x5f\xf0\x9d\x95\x93";

     std::string src = "fn $function($param_a : i32, $param_b : f32) { return; }";
     src = utils::ReplaceAll(src, "$function", function_ident);
     src = utils::ReplaceAll(src, "$param_a", param_a_ident);
     src = utils::ReplaceAll(src, "$param_b", param_b_ident);

     auto p = parser(src);
     auto attrs = p->attribute_list();
     EXPECT_FALSE(p->has_error()) << p->error();
     ASSERT_FALSE(attrs.errored);
     EXPECT_FALSE(attrs.matched);
     auto f = p->function_decl(attrs.value);
     EXPECT_FALSE(p->has_error()) << p->error();
     EXPECT_FALSE(f.errored);
     EXPECT_TRUE(f.matched);
     ASSERT_NE(f.value, nullptr);

     EXPECT_EQ(f->name->symbol, p->builder().Symbols().Get(function_ident));
     EXPECT_EQ(f->return_type, nullptr);

     ASSERT_EQ(f->params.Length(), 2u);
     EXPECT_EQ(f->params[0]->name->symbol, p->builder().Symbols().Get(param_a_ident));
     EXPECT_EQ(f->params[1]->name->symbol, p->builder().Symbols().Get(param_b_ident));

     EXPECT_EQ(f->return_type, nullptr);

     auto* body = f->body;
     ASSERT_EQ(body->statements.Length(), 1u);
     EXPECT_TRUE(body->statements[0]->Is<ast::ReturnStatement>());
 }

 TEST_F(WGSLParserTest, FunctionDecl_AttributeList) {
     auto p = parser("@workgroup_size(2, 3, 4) fn main() { return; }");
     auto attrs = p->attribute_list();
     EXPECT_FALSE(p->has_error()) << p->error();
     ASSERT_FALSE(attrs.errored);
     ASSERT_TRUE(attrs.matched);
     auto f = p->function_decl(attrs.value);
     EXPECT_FALSE(p->has_error()) << p->error();
     EXPECT_FALSE(f.errored);
     EXPECT_TRUE(f.matched);
     ASSERT_NE(f.value, nullptr);

     EXPECT_EQ(f->name->symbol, p->builder().Symbols().Get("main"));
     EXPECT_EQ(f->return_type, nullptr);
     ASSERT_EQ(f->params.Length(), 0u);

     auto& attributes = f->attributes;
     ASSERT_EQ(attributes.Length(), 1u);
     ASSERT_TRUE(attributes[0]->Is<ast::WorkgroupAttribute>());

     auto values = attributes[0]->As<ast::WorkgroupAttribute>()->Values();

     ASSERT_TRUE(values[0]->Is<ast::IntLiteralExpression>());
     EXPECT_EQ(values[0]->As<ast::IntLiteralExpression>()->value, 2);
     EXPECT_EQ(values[0]->As<ast::IntLiteralExpression>()->suffix,
               ast::IntLiteralExpression::Suffix::kNone);

     ASSERT_TRUE(values[1]->Is<ast::IntLiteralExpression>());
     EXPECT_EQ(values[1]->As<ast::IntLiteralExpression>()->value, 3);
     EXPECT_EQ(values[1]->As<ast::IntLiteralExpression>()->suffix,
               ast::IntLiteralExpression::Suffix::kNone);

     ASSERT_TRUE(values[2]->Is<ast::IntLiteralExpression>());
     EXPECT_EQ(values[2]->As<ast::IntLiteralExpression>()->value, 4);
     EXPECT_EQ(values[2]->As<ast::IntLiteralExpression>()->suffix,
               ast::IntLiteralExpression::Suffix::kNone);

     auto* body = f->body;
     ASSERT_EQ(body->statements.Length(), 1u);
     EXPECT_TRUE(body->statements[0]->Is<ast::ReturnStatement>());
 }

 TEST_F(WGSLParserTest, FunctionDecl_AttributeList_MultipleEntries) {
     auto p = parser(R"(
 @workgroup_size(2, 3, 4) @compute
 fn main() { return; })");
     auto attrs = p->attribute_list();
     EXPECT_FALSE(p->has_error()) << p->error();
     ASSERT_FALSE(attrs.errored);
     ASSERT_TRUE(attrs.matched);
     auto f = p->function_decl(attrs.value);
     EXPECT_FALSE(p->has_error()) << p->error();
     EXPECT_FALSE(f.errored);
     EXPECT_TRUE(f.matched);
     ASSERT_NE(f.value, nullptr);

     EXPECT_EQ(f->name->symbol, p->builder().Symbols().Get("main"));
     EXPECT_EQ(f->return_type, nullptr);
     ASSERT_EQ(f->params.Length(), 0u);

     auto& attributes = f->attributes;
     ASSERT_EQ(attributes.Length(), 2u);

     ASSERT_TRUE(attributes[0]->Is<ast::WorkgroupAttribute>());
     auto values = attributes[0]->As<ast::WorkgroupAttribute>()->Values();

     ASSERT_TRUE(values[0]->Is<ast::IntLiteralExpression>());
     EXPECT_EQ(values[0]->As<ast::IntLiteralExpression>()->value, 2);
     EXPECT_EQ(values[0]->As<ast::IntLiteralExpression>()->suffix,
               ast::IntLiteralExpression::Suffix::kNone);

     ASSERT_TRUE(values[1]->Is<ast::IntLiteralExpression>());
     EXPECT_EQ(values[1]->As<ast::IntLiteralExpression>()->value, 3);
     EXPECT_EQ(values[1]->As<ast::IntLiteralExpression>()->suffix,
               ast::IntLiteralExpression::Suffix::kNone);

     ASSERT_TRUE(values[2]->Is<ast::IntLiteralExpression>());
     EXPECT_EQ(values[2]->As<ast::IntLiteralExpression>()->value, 4);
     EXPECT_EQ(values[2]->As<ast::IntLiteralExpression>()->suffix,
               ast::IntLiteralExpression::Suffix::kNone);

     ASSERT_TRUE(attributes[1]->Is<ast::StageAttribute>());
     EXPECT_EQ(attributes[1]->As<ast::StageAttribute>()->stage, ast::PipelineStage::kCompute);

     auto* body = f->body;
     ASSERT_EQ(body->statements.Length(), 1u);
     EXPECT_TRUE(body->statements[0]->Is<ast::ReturnStatement>());
 }

 TEST_F(WGSLParserTest, FunctionDecl_AttributeList_MultipleLists) {
     auto p = parser(R"(
 @workgroup_size(2, 3, 4)
 @compute
 fn main() { return; })");
     auto attributes = p->attribute_list();
     EXPECT_FALSE(p->has_error()) << p->error();
     ASSERT_FALSE(attributes.errored);
     ASSERT_TRUE(attributes.matched);
     auto f = p->function_decl(attributes.value);
     EXPECT_FALSE(p->has_error()) << p->error();
     EXPECT_FALSE(f.errored);
     EXPECT_TRUE(f.matched);
     ASSERT_NE(f.value, nullptr);

     EXPECT_EQ(f->name->symbol, p->builder().Symbols().Get("main"));
     EXPECT_EQ(f->return_type, nullptr);
     ASSERT_EQ(f->params.Length(), 0u);

     auto& attrs = f->attributes;
     ASSERT_EQ(attrs.Length(), 2u);

     ASSERT_TRUE(attrs[0]->Is<ast::WorkgroupAttribute>());
     auto values = attrs[0]->As<ast::WorkgroupAttribute>()->Values();

     ASSERT_TRUE(values[0]->Is<ast::IntLiteralExpression>());
     EXPECT_EQ(values[0]->As<ast::IntLiteralExpression>()->value, 2);
     EXPECT_EQ(values[0]->As<ast::IntLiteralExpression>()->suffix,
               ast::IntLiteralExpression::Suffix::kNone);

     ASSERT_TRUE(values[1]->Is<ast::IntLiteralExpression>());
     EXPECT_EQ(values[1]->As<ast::IntLiteralExpression>()->value, 3);
     EXPECT_EQ(values[1]->As<ast::IntLiteralExpression>()->suffix,
               ast::IntLiteralExpression::Suffix::kNone);

     ASSERT_TRUE(values[2]->Is<ast::IntLiteralExpression>());
     EXPECT_EQ(values[2]->As<ast::IntLiteralExpression>()->value, 4);
     EXPECT_EQ(values[2]->As<ast::IntLiteralExpression>()->suffix,
               ast::IntLiteralExpression::Suffix::kNone);

     ASSERT_TRUE(attrs[1]->Is<ast::StageAttribute>());
     EXPECT_EQ(attrs[1]->As<ast::StageAttribute>()->stage, ast::PipelineStage::kCompute);

     auto* body = f->body;
     ASSERT_EQ(body->statements.Length(), 1u);
     EXPECT_TRUE(body->statements[0]->Is<ast::ReturnStatement>());
 }

 TEST_F(WGSLParserTest, FunctionDecl_ReturnTypeAttributeList) {
     auto p = parser("fn main() -> @location(1) f32 { return 1.0; }");
     auto attrs = p->attribute_list();
     EXPECT_FALSE(p->has_error()) << p->error();
     ASSERT_FALSE(attrs.errored);
     EXPECT_FALSE(attrs.matched);
     auto f = p->function_decl(attrs.value);
     EXPECT_FALSE(p->has_error()) << p->error();
     EXPECT_FALSE(f.errored);
     EXPECT_TRUE(f.matched);
     ASSERT_NE(f.value, nullptr);

     EXPECT_EQ(f->name->symbol, p->builder().Symbols().Get("main"));
     ASSERT_NE(f->return_type, nullptr);

     ast::CheckIdentifier(f->return_type, "f32");

     ASSERT_EQ(f->params.Length(), 0u);

     auto& attributes = f->attributes;
     EXPECT_EQ(attributes.Length(), 0u);

     auto& ret_type_attributes = f->return_type_attributes;
     ASSERT_EQ(ret_type_attributes.Length(), 1u);
     auto* loc = ret_type_attributes[0]->As<ast::LocationAttribute>();
     ASSERT_TRUE(loc != nullptr);
     EXPECT_TRUE(loc->expr->Is<ast::IntLiteralExpression>());

     auto* exp = loc->expr->As<ast::IntLiteralExpression>();
     EXPECT_EQ(1u, exp->value);

     auto* body = f->body;
     ASSERT_EQ(body->statements.Length(), 1u);
     EXPECT_TRUE(body->statements[0]->Is<ast::ReturnStatement>());
 }

 TEST_F(WGSLParserTest, FunctionDecl_MustUse) {
     auto p = parser("@must_use fn main() { return; }");
     auto attrs = p->attribute_list();
     EXPECT_FALSE(p->has_error()) << p->error();
     ASSERT_FALSE(attrs.errored);
     ASSERT_TRUE(attrs.matched);
     auto f = p->function_decl(attrs.value);
     EXPECT_FALSE(p->has_error()) << p->error();
     EXPECT_FALSE(f.errored);
     EXPECT_TRUE(f.matched);
     ASSERT_NE(f.value, nullptr);

     auto& attributes = f->attributes;
     ASSERT_EQ(attributes.Length(), 1u);
     ASSERT_TRUE(attributes[0]->Is<ast::MustUseAttribute>());
 }

 TEST_F(WGSLParserTest, FunctionDecl_InvalidHeader) {
     auto p = parser("fn main() -> { }");
     auto attrs = p->attribute_list();
     EXPECT_FALSE(p->has_error()) << p->error();
     ASSERT_FALSE(attrs.errored);
     EXPECT_FALSE(attrs.matched);
     auto f = p->function_decl(attrs.value);
     EXPECT_TRUE(f.errored);
     EXPECT_FALSE(f.matched);
     EXPECT_TRUE(p->has_error());
     EXPECT_EQ(f.value, nullptr);
     EXPECT_EQ(p->error(), "1:14: unable to determine function return type");
 }

 TEST_F(WGSLParserTest, FunctionDecl_InvalidBody) {
     auto p = parser("fn main() { return }");
     auto attrs = p->attribute_list();
     EXPECT_FALSE(p->has_error()) << p->error();
     ASSERT_FALSE(attrs.errored);
     EXPECT_FALSE(attrs.matched);
     auto f = p->function_decl(attrs.value);
     EXPECT_TRUE(f.errored);
     EXPECT_FALSE(f.matched);
     EXPECT_TRUE(p->has_error());
     EXPECT_EQ(f.value, nullptr);
     EXPECT_EQ(p->error(), "1:20: expected ';' for return statement");
 }

 TEST_F(WGSLParserTest, FunctionDecl_MissingLeftBrace) {
     auto p = parser("fn main() return; }");
     auto attrs = p->attribute_list();
     EXPECT_FALSE(p->has_error()) << p->error();
     ASSERT_FALSE(attrs.errored);
     EXPECT_FALSE(attrs.matched);
     auto f = p->function_decl(attrs.value);
     EXPECT_TRUE(f.errored);
     EXPECT_FALSE(f.matched);
     EXPECT_TRUE(p->has_error());
     EXPECT_EQ(f.value, nullptr);
     EXPECT_EQ(p->error(), "1:11: expected '{' for function body");
 }

 }  // namespace
 }  // namespace tint::wgsl::reader
	// Copyright 2020 The Tint Authors.
	//
	// Licensed under the Apache License, Version 2.0 (the "License");
	// you may not use this file except in compliance with the License.
	// You may obtain a copy of the License at
	//
	// http://www.apache.org/licenses/LICENSE-2.0
	//
	// Unless required by applicable law or agreed to in writing, software
	// distributed under the License is distributed on an "AS IS" BASIS,
	// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	// See the License for the specific language governing permissions and
	// limitations under the License.

	#include "src/tint/lang/wgsl/ast/test_helper.h"
	#include "src/tint/lang/wgsl/ast/workgroup_attribute.h"
	#include "src/tint/lang/wgsl/reader/parser/test_helper.h"
	#include "src/tint/utils/text/string.h"

	namespace tint::wgsl::reader {
	namespace {

	TEST_F(WGSLParserTest, FunctionDecl) {
	auto p = parser("fn main(a : i32, b : f32) { return; }");
	auto attrs = p->attribute_list();
	EXPECT_FALSE(p->has_error()) << p->error();
	ASSERT_FALSE(attrs.errored);
	EXPECT_FALSE(attrs.matched);
	auto f = p->function_decl(attrs.value);
	EXPECT_FALSE(p->has_error()) << p->error();
	EXPECT_FALSE(f.errored);
	EXPECT_TRUE(f.matched);
	ASSERT_NE(f.value, nullptr);

	EXPECT_EQ(f->name->symbol, p->builder().Symbols().Get("main"));
	EXPECT_EQ(f->return_type, nullptr);

	ASSERT_EQ(f->params.Length(), 2u);
	EXPECT_EQ(f->params[0]->name->symbol, p->builder().Symbols().Get("a"));
	EXPECT_EQ(f->params[1]->name->symbol, p->builder().Symbols().Get("b"));

	EXPECT_EQ(f->return_type, nullptr);

	auto* body = f->body;
	ASSERT_EQ(body->statements.Length(), 1u);
	EXPECT_TRUE(body->statements[0]->Is<ast::ReturnStatement>());
	}

	TEST_F(WGSLParserTest, FunctionDecl_Unicode) {
	const std::string function_ident = // "𝗳𝘂𝗻𝗰𝘁𝗶𝗼𝗻"
	"\xf0\x9d\x97\xb3\xf0\x9d\x98\x82\xf0\x9d\x97\xbb\xf0\x9d\x97\xb0\xf0\x9d"
	"\x98\x81\xf0\x9d\x97\xb6\xf0\x9d\x97\xbc\xf0\x9d\x97\xbb";

	const std::string param_a_ident = // "𝓹𝓪𝓻𝓪𝓶_𝓪"
	"\xf0\x9d\x93\xb9\xf0\x9d\x93\xaa\xf0\x9d\x93\xbb\xf0\x9d\x93\xaa\xf0\x9d"
	"\x93\xb6\x5f\xf0\x9d\x93\xaa";

	const std::string param_b_ident = // "𝕡𝕒𝕣𝕒𝕞_𝕓"
	"\xf0\x9d\x95\xa1\xf0\x9d\x95\x92\xf0\x9d\x95\xa3\xf0\x9d\x95\x92\xf0\x9d"
	"\x95\x9e\x5f\xf0\x9d\x95\x93";

	std::string src = "fn $function($param_a : i32, $param_b : f32) { return; }";
	src = utils::ReplaceAll(src, "$function", function_ident);
	src = utils::ReplaceAll(src, "$param_a", param_a_ident);
	src = utils::ReplaceAll(src, "$param_b", param_b_ident);

	auto p = parser(src);
	auto attrs = p->attribute_list();
	EXPECT_FALSE(p->has_error()) << p->error();
	ASSERT_FALSE(attrs.errored);
	EXPECT_FALSE(attrs.matched);
	auto f = p->function_decl(attrs.value);
	EXPECT_FALSE(p->has_error()) << p->error();
	EXPECT_FALSE(f.errored);
	EXPECT_TRUE(f.matched);
	ASSERT_NE(f.value, nullptr);

	EXPECT_EQ(f->name->symbol, p->builder().Symbols().Get(function_ident));
	EXPECT_EQ(f->return_type, nullptr);

	ASSERT_EQ(f->params.Length(), 2u);
	EXPECT_EQ(f->params[0]->name->symbol, p->builder().Symbols().Get(param_a_ident));
	EXPECT_EQ(f->params[1]->name->symbol, p->builder().Symbols().Get(param_b_ident));

	EXPECT_EQ(f->return_type, nullptr);

	auto* body = f->body;
	ASSERT_EQ(body->statements.Length(), 1u);
	EXPECT_TRUE(body->statements[0]->Is<ast::ReturnStatement>());
	}

	TEST_F(WGSLParserTest, FunctionDecl_AttributeList) {
	auto p = parser("@workgroup_size(2, 3, 4) fn main() { return; }");
	auto attrs = p->attribute_list();
	EXPECT_FALSE(p->has_error()) << p->error();
	ASSERT_FALSE(attrs.errored);
	ASSERT_TRUE(attrs.matched);
	auto f = p->function_decl(attrs.value);
	EXPECT_FALSE(p->has_error()) << p->error();
	EXPECT_FALSE(f.errored);
	EXPECT_TRUE(f.matched);
	ASSERT_NE(f.value, nullptr);

	EXPECT_EQ(f->name->symbol, p->builder().Symbols().Get("main"));
	EXPECT_EQ(f->return_type, nullptr);
	ASSERT_EQ(f->params.Length(), 0u);

	auto& attributes = f->attributes;
	ASSERT_EQ(attributes.Length(), 1u);
	ASSERT_TRUE(attributes[0]->Is<ast::WorkgroupAttribute>());

	auto values = attributes[0]->As<ast::WorkgroupAttribute>()->Values();

	ASSERT_TRUE(values[0]->Is<ast::IntLiteralExpression>());
	EXPECT_EQ(values[0]->As<ast::IntLiteralExpression>()->value, 2);
	EXPECT_EQ(values[0]->As<ast::IntLiteralExpression>()->suffix,
	ast::IntLiteralExpression::Suffix::kNone);

	ASSERT_TRUE(values[1]->Is<ast::IntLiteralExpression>());
	EXPECT_EQ(values[1]->As<ast::IntLiteralExpression>()->value, 3);
	EXPECT_EQ(values[1]->As<ast::IntLiteralExpression>()->suffix,
	ast::IntLiteralExpression::Suffix::kNone);

	ASSERT_TRUE(values[2]->Is<ast::IntLiteralExpression>());
	EXPECT_EQ(values[2]->As<ast::IntLiteralExpression>()->value, 4);
	EXPECT_EQ(values[2]->As<ast::IntLiteralExpression>()->suffix,
	ast::IntLiteralExpression::Suffix::kNone);

	auto* body = f->body;
	ASSERT_EQ(body->statements.Length(), 1u);
	EXPECT_TRUE(body->statements[0]->Is<ast::ReturnStatement>());
	}

	TEST_F(WGSLParserTest, FunctionDecl_AttributeList_MultipleEntries) {
	auto p = parser(R"(
	@workgroup_size(2, 3, 4) @compute
	fn main() { return; })");
	auto attrs = p->attribute_list();
	EXPECT_FALSE(p->has_error()) << p->error();
	ASSERT_FALSE(attrs.errored);
	ASSERT_TRUE(attrs.matched);
	auto f = p->function_decl(attrs.value);
	EXPECT_FALSE(p->has_error()) << p->error();
	EXPECT_FALSE(f.errored);
	EXPECT_TRUE(f.matched);
	ASSERT_NE(f.value, nullptr);

	EXPECT_EQ(f->name->symbol, p->builder().Symbols().Get("main"));
	EXPECT_EQ(f->return_type, nullptr);
	ASSERT_EQ(f->params.Length(), 0u);

	auto& attributes = f->attributes;
	ASSERT_EQ(attributes.Length(), 2u);

	ASSERT_TRUE(attributes[0]->Is<ast::WorkgroupAttribute>());
	auto values = attributes[0]->As<ast::WorkgroupAttribute>()->Values();

	ASSERT_TRUE(values[0]->Is<ast::IntLiteralExpression>());
	EXPECT_EQ(values[0]->As<ast::IntLiteralExpression>()->value, 2);
	EXPECT_EQ(values[0]->As<ast::IntLiteralExpression>()->suffix,
	ast::IntLiteralExpression::Suffix::kNone);

	ASSERT_TRUE(values[1]->Is<ast::IntLiteralExpression>());
	EXPECT_EQ(values[1]->As<ast::IntLiteralExpression>()->value, 3);
	EXPECT_EQ(values[1]->As<ast::IntLiteralExpression>()->suffix,
	ast::IntLiteralExpression::Suffix::kNone);

	ASSERT_TRUE(values[2]->Is<ast::IntLiteralExpression>());
	EXPECT_EQ(values[2]->As<ast::IntLiteralExpression>()->value, 4);
	EXPECT_EQ(values[2]->As<ast::IntLiteralExpression>()->suffix,
	ast::IntLiteralExpression::Suffix::kNone);

	ASSERT_TRUE(attributes[1]->Is<ast::StageAttribute>());
	EXPECT_EQ(attributes[1]->As<ast::StageAttribute>()->stage, ast::PipelineStage::kCompute);

	auto* body = f->body;
	ASSERT_EQ(body->statements.Length(), 1u);
	EXPECT_TRUE(body->statements[0]->Is<ast::ReturnStatement>());
	}

	TEST_F(WGSLParserTest, FunctionDecl_AttributeList_MultipleLists) {
	auto p = parser(R"(
	@workgroup_size(2, 3, 4)
	@compute
	fn main() { return; })");
	auto attributes = p->attribute_list();
	EXPECT_FALSE(p->has_error()) << p->error();
	ASSERT_FALSE(attributes.errored);
	ASSERT_TRUE(attributes.matched);
	auto f = p->function_decl(attributes.value);
	EXPECT_FALSE(p->has_error()) << p->error();
	EXPECT_FALSE(f.errored);
	EXPECT_TRUE(f.matched);
	ASSERT_NE(f.value, nullptr);

	EXPECT_EQ(f->name->symbol, p->builder().Symbols().Get("main"));
	EXPECT_EQ(f->return_type, nullptr);
	ASSERT_EQ(f->params.Length(), 0u);

	auto& attrs = f->attributes;
	ASSERT_EQ(attrs.Length(), 2u);

	ASSERT_TRUE(attrs[0]->Is<ast::WorkgroupAttribute>());
	auto values = attrs[0]->As<ast::WorkgroupAttribute>()->Values();

	ASSERT_TRUE(values[0]->Is<ast::IntLiteralExpression>());
	EXPECT_EQ(values[0]->As<ast::IntLiteralExpression>()->value, 2);
	EXPECT_EQ(values[0]->As<ast::IntLiteralExpression>()->suffix,
	ast::IntLiteralExpression::Suffix::kNone);

	ASSERT_TRUE(values[1]->Is<ast::IntLiteralExpression>());
	EXPECT_EQ(values[1]->As<ast::IntLiteralExpression>()->value, 3);
	EXPECT_EQ(values[1]->As<ast::IntLiteralExpression>()->suffix,
	ast::IntLiteralExpression::Suffix::kNone);

	ASSERT_TRUE(values[2]->Is<ast::IntLiteralExpression>());
	EXPECT_EQ(values[2]->As<ast::IntLiteralExpression>()->value, 4);
	EXPECT_EQ(values[2]->As<ast::IntLiteralExpression>()->suffix,
	ast::IntLiteralExpression::Suffix::kNone);

	ASSERT_TRUE(attrs[1]->Is<ast::StageAttribute>());
	EXPECT_EQ(attrs[1]->As<ast::StageAttribute>()->stage, ast::PipelineStage::kCompute);

	auto* body = f->body;
	ASSERT_EQ(body->statements.Length(), 1u);
	EXPECT_TRUE(body->statements[0]->Is<ast::ReturnStatement>());
	}

	TEST_F(WGSLParserTest, FunctionDecl_ReturnTypeAttributeList) {
	auto p = parser("fn main() -> @location(1) f32 { return 1.0; }");
	auto attrs = p->attribute_list();
	EXPECT_FALSE(p->has_error()) << p->error();
	ASSERT_FALSE(attrs.errored);
	EXPECT_FALSE(attrs.matched);
	auto f = p->function_decl(attrs.value);
	EXPECT_FALSE(p->has_error()) << p->error();
	EXPECT_FALSE(f.errored);
	EXPECT_TRUE(f.matched);
	ASSERT_NE(f.value, nullptr);

	EXPECT_EQ(f->name->symbol, p->builder().Symbols().Get("main"));
	ASSERT_NE(f->return_type, nullptr);

	ast::CheckIdentifier(f->return_type, "f32");

	ASSERT_EQ(f->params.Length(), 0u);

	auto& attributes = f->attributes;
	EXPECT_EQ(attributes.Length(), 0u);

	auto& ret_type_attributes = f->return_type_attributes;
	ASSERT_EQ(ret_type_attributes.Length(), 1u);
	auto* loc = ret_type_attributes[0]->As<ast::LocationAttribute>();
	ASSERT_TRUE(loc != nullptr);
	EXPECT_TRUE(loc->expr->Is<ast::IntLiteralExpression>());

	auto* exp = loc->expr->As<ast::IntLiteralExpression>();
	EXPECT_EQ(1u, exp->value);

	auto* body = f->body;
	ASSERT_EQ(body->statements.Length(), 1u);
	EXPECT_TRUE(body->statements[0]->Is<ast::ReturnStatement>());
	}

	TEST_F(WGSLParserTest, FunctionDecl_MustUse) {
	auto p = parser("@must_use fn main() { return; }");
	auto attrs = p->attribute_list();
	EXPECT_FALSE(p->has_error()) << p->error();
	ASSERT_FALSE(attrs.errored);
	ASSERT_TRUE(attrs.matched);
	auto f = p->function_decl(attrs.value);
	EXPECT_FALSE(p->has_error()) << p->error();
	EXPECT_FALSE(f.errored);
	EXPECT_TRUE(f.matched);
	ASSERT_NE(f.value, nullptr);

	auto& attributes = f->attributes;
	ASSERT_EQ(attributes.Length(), 1u);
	ASSERT_TRUE(attributes[0]->Is<ast::MustUseAttribute>());
	}

	TEST_F(WGSLParserTest, FunctionDecl_InvalidHeader) {
	auto p = parser("fn main() -> { }");
	auto attrs = p->attribute_list();
	EXPECT_FALSE(p->has_error()) << p->error();
	ASSERT_FALSE(attrs.errored);
	EXPECT_FALSE(attrs.matched);
	auto f = p->function_decl(attrs.value);
	EXPECT_TRUE(f.errored);
	EXPECT_FALSE(f.matched);
	EXPECT_TRUE(p->has_error());
	EXPECT_EQ(f.value, nullptr);
	EXPECT_EQ(p->error(), "1:14: unable to determine function return type");
	}

	TEST_F(WGSLParserTest, FunctionDecl_InvalidBody) {
	auto p = parser("fn main() { return }");
	auto attrs = p->attribute_list();
	EXPECT_FALSE(p->has_error()) << p->error();
	ASSERT_FALSE(attrs.errored);
	EXPECT_FALSE(attrs.matched);
	auto f = p->function_decl(attrs.value);
	EXPECT_TRUE(f.errored);
	EXPECT_FALSE(f.matched);
	EXPECT_TRUE(p->has_error());
	EXPECT_EQ(f.value, nullptr);
	EXPECT_EQ(p->error(), "1:20: expected ';' for return statement");
	}

	TEST_F(WGSLParserTest, FunctionDecl_MissingLeftBrace) {
	auto p = parser("fn main() return; }");
	auto attrs = p->attribute_list();
	EXPECT_FALSE(p->has_error()) << p->error();
	ASSERT_FALSE(attrs.errored);
	EXPECT_FALSE(attrs.matched);
	auto f = p->function_decl(attrs.value);
	EXPECT_TRUE(f.errored);
	EXPECT_FALSE(f.matched);
	EXPECT_TRUE(p->has_error());
	EXPECT_EQ(f.value, nullptr);
	EXPECT_EQ(p->error(), "1:11: expected '{' for function body");
	}

	} // namespace
	} // namespace tint::wgsl::reader