diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index 3d71fc7210..30b6e04834 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -191,6 +191,7 @@ if(TINT_BUILD_SPV_PARSER)
 endif()
 
 set(TINT_TEST_SRCS
+  ast/array_accessor_expression_test.cc
   ast/binding_decoration_test.cc
   ast/bool_literal_test.cc
   ast/builtin_decoration_test.cc
diff --git a/src/ast/array_accessor_expression.cc b/src/ast/array_accessor_expression.cc
index a98b436a5c..239748462e 100644
--- a/src/ast/array_accessor_expression.cc
+++ b/src/ast/array_accessor_expression.cc
@@ -17,6 +17,8 @@
 namespace tint {
 namespace ast {
 
+ArrayAccessorExpression::ArrayAccessorExpression() : Expression() {}
+
 ArrayAccessorExpression::ArrayAccessorExpression(
     std::unique_ptr<Expression> array,
     std::unique_ptr<Expression> idx_expr)
diff --git a/src/ast/array_accessor_expression.h b/src/ast/array_accessor_expression.h
index ddffdee458..59880855da 100644
--- a/src/ast/array_accessor_expression.h
+++ b/src/ast/array_accessor_expression.h
@@ -27,6 +27,8 @@ namespace ast {
 /// An array accessor expression
 class ArrayAccessorExpression : public Expression {
  public:
+  /// Constructor
+  ArrayAccessorExpression();
   /// Constructor
   /// @param array the array
   /// @param idx_expr the index expression
diff --git a/src/ast/array_accessor_expression_test.cc b/src/ast/array_accessor_expression_test.cc
new file mode 100644
index 0000000000..9e293227b3
--- /dev/null
+++ b/src/ast/array_accessor_expression_test.cc
@@ -0,0 +1,92 @@
+// 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/array_accessor_expression.h"
+
+#include "gtest/gtest.h"
+#include "src/ast/identifier_expression.h"
+
+namespace tint {
+namespace ast {
+
+using ArrayAccessorExpressionTest = testing::Test;
+
+TEST_F(ArrayAccessorExpressionTest, Create) {
+  auto ary = std::make_unique<IdentifierExpression>("ary");
+  auto idx = std::make_unique<IdentifierExpression>("idx");
+
+  auto ary_ptr = ary.get();
+  auto idx_ptr = idx.get();
+
+  ArrayAccessorExpression exp(std::move(ary), std::move(idx));
+  ASSERT_EQ(exp.array(), ary_ptr);
+  ASSERT_EQ(exp.idx_expr(), idx_ptr);
+}
+TEST_F(ArrayAccessorExpressionTest, CreateWithSource) {
+  auto ary = std::make_unique<IdentifierExpression>("ary");
+  auto idx = std::make_unique<IdentifierExpression>("idx");
+
+  ArrayAccessorExpression exp(Source{20, 2}, std::move(ary), std::move(idx));
+  auto src = exp.source();
+  EXPECT_EQ(src.line, 20);
+  EXPECT_EQ(src.column, 2);
+}
+
+TEST_F(ArrayAccessorExpressionTest, IsArrayAccessor) {
+  ArrayAccessorExpression exp;
+  EXPECT_TRUE(exp.IsArrayAccessor());
+}
+
+
+TEST_F(ArrayAccessorExpressionTest, IsValid) {
+  auto ary = std::make_unique<IdentifierExpression>("ary");
+  auto idx = std::make_unique<IdentifierExpression>("idx");
+
+  ArrayAccessorExpression exp(std::move(ary), std::move(idx));
+  EXPECT_TRUE(exp.IsValid());
+}
+
+TEST_F(ArrayAccessorExpressionTest, IsValid_MissingArray) {
+  auto idx = std::make_unique<IdentifierExpression>("idx");
+
+  ArrayAccessorExpression exp;
+  exp.set_idx_expr(std::move(idx));
+  EXPECT_FALSE(exp.IsValid());
+}
+
+TEST_F(ArrayAccessorExpressionTest, IsValid_MissingIndex) {
+  auto ary = std::make_unique<IdentifierExpression>("ary");
+
+  ArrayAccessorExpression exp;
+  exp.set_array(std::move(ary));
+  EXPECT_FALSE(exp.IsValid());
+}
+
+TEST_F(ArrayAccessorExpressionTest, ToStr) {
+  auto ary = std::make_unique<IdentifierExpression>("ary");
+  auto idx = std::make_unique<IdentifierExpression>("idx");
+
+  ArrayAccessorExpression exp(std::move(ary), std::move(idx));
+  std::ostringstream out;
+  exp.to_str(out, 0);
+
+  EXPECT_EQ(out.str(), R"(ArrayAccessor{
+  Identifier{ary}
+  Identifier{idx}
+}
+)");
+}
+
+}  // namespace ast
+}  // namespace tint