Add ConstInitializerExpression tests

This CL adds unit tests for the const initializer expression.

Bug: tint:11
Change-Id: I9fb9dd77447ac20921997614816cd75272d4e05a
Reviewed-on: https://dawn-review.googlesource.com/c/tint/+/16463
Reviewed-by: David Neto <dneto@google.com>

src/CMakeLists.txt

@@ -203,6 +203,7 @@ set(TINT_TEST_SRCS
   ast/call_expression_test.cc
   ast/case_statement_test.cc
   ast/cast_expression_test.cc
+  ast/const_initializer_expression_test.cc
   ast/entry_point_test.cc
   ast/import_test.cc
   ast/int_literal_test.cc

src/ast/const_initializer_expression.cc

@@ -17,6 +17,9 @@
 namespace tint {
 namespace ast {
 
+ConstInitializerExpression::ConstInitializerExpression()
+    : InitializerExpression() {}
+
 ConstInitializerExpression::ConstInitializerExpression(
     std::unique_ptr<Literal> literal)
     : InitializerExpression(), literal_(std::move(literal)) {}

src/ast/const_initializer_expression.h

@@ -27,6 +27,8 @@ namespace ast {
 /// A constant initializer
 class ConstInitializerExpression : public InitializerExpression {
  public:
+  /// Constructor
+  ConstInitializerExpression();
   /// Constructor
   /// @param literal the const literal
   explicit ConstInitializerExpression(std::unique_ptr<Literal> literal);

src/ast/const_initializer_expression_test.cc

@@ -0,0 +1,61 @@
+// 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/ast/const_initializer_expression.h"
+
+#include "gtest/gtest.h"
+#include "src/ast/bool_literal.h"
+
+namespace tint {
+namespace ast {
+
+using ConstInitializerExpressionTest = testing::Test;
+
+TEST_F(ConstInitializerExpressionTest, Creation) {
+  auto b = std::make_unique<BoolLiteral>(true);
+  auto b_ptr = b.get();
+  ConstInitializerExpression c(std::move(b));
+  EXPECT_EQ(c.literal(), b_ptr);
+}
+
+TEST_F(ConstInitializerExpressionTest, Creation_WithSource) {
+  auto b = std::make_unique<BoolLiteral>(true);
+  ConstInitializerExpression c(Source{20, 2}, std::move(b));
+  auto src = c.source();
+  EXPECT_EQ(src.line, 20);
+  EXPECT_EQ(src.column, 2);
+}
+
+TEST_F(ConstInitializerExpressionTest, IsValid) {
+  auto b = std::make_unique<BoolLiteral>(true);
+  ConstInitializerExpression c(std::move(b));
+  EXPECT_TRUE(c.IsValid());
+}
+
+TEST_F(ConstInitializerExpressionTest, IsValid_MissingLiteral) {
+  ConstInitializerExpression c;
+  EXPECT_FALSE(c.IsValid());
+}
+
+TEST_F(ConstInitializerExpressionTest, ToStr) {
+  auto b = std::make_unique<BoolLiteral>(true);
+  ConstInitializerExpression c(std::move(b));
+  std::ostringstream out;
+  c.to_str(out, 2);
+  EXPECT_EQ(out.str(), R"(  ConstInitializer{true}
+)");
+}
+
+}  // namespace ast
+}  // namespace tint