Add LoopStatement AST tests This CL adds tests for the loop statement AST node. Bug: tint: 11 Change-Id: I32a3e1d4d40d21e00f4022bd1a2d03ba2ef4f404 Reviewed-on: https://dawn-review.googlesource.com/c/tint/+/16563 Reviewed-by: Sarah Mashayekhi <sarahmashay@google.com>

diff --git a/src/ast/loop_statement.cc b/src/ast/loop_statement.cc
index b0e645b..e99c87c 100644
--- a/src/ast/loop_statement.cc
+++ b/src/ast/loop_statement.cc

@@ -17,6 +17,8 @@
 namespace tint {
 namespace ast {
 
+LoopStatement::LoopStatement() : Statement() {}
+
 LoopStatement::LoopStatement(std::vector<std::unique_ptr<Statement>> body,
                              std::vector<std::unique_ptr<Statement>> continuing)
     : Statement(), body_(std::move(body)), continuing_(std::move(continuing)) {}
@@ -31,6 +33,14 @@
 LoopStatement::~LoopStatement() = default;
 
 bool LoopStatement::IsValid() const {
+  for (const auto& stmt : body_) {
+    if (stmt == nullptr || !stmt->IsValid())
+      return false;
+  }
+  for (const auto& stmt : continuing_) {
+    if (stmt == nullptr || !stmt->IsValid())
+      return false;
+  }
   return true;
 }
 
@@ -41,14 +51,16 @@
   for (const auto& stmt : body_)
     stmt->to_str(out, indent + 2);
 
-  make_indent(out, indent + 2);
-  out << "continuing {" << std::endl;
-
-  for (const auto& stmt : continuing_)
-    stmt->to_str(out, indent + 4);
-
-  make_indent(out, indent + 2);
-  out << "}" << std::endl;
+  if (continuing_.size() > 0) {
+    make_indent(out, indent + 2);
+    out << "continuing {" << std::endl;
+  
+    for (const auto& stmt : continuing_)
+      stmt->to_str(out, indent + 4);
+  
+    make_indent(out, indent + 2);
+    out << "}" << std::endl;
+  }
 
   make_indent(out, indent);
   out << "}" << std::endl;

diff --git a/src/ast/loop_statement.h b/src/ast/loop_statement.h
index 99acd96..917eaa6 100644
--- a/src/ast/loop_statement.h
+++ b/src/ast/loop_statement.h

@@ -28,6 +28,8 @@
 class LoopStatement : public Statement {
  public:
   /// Constructor
+  LoopStatement();
+  /// Constructor
   /// @param body the body statements
   /// @param continuing the continuing statements
   LoopStatement(std::vector<std::unique_ptr<Statement>> body,

diff --git a/src/ast/loop_statement_test.cc b/src/ast/loop_statement_test.cc
new file mode 100644
index 0000000..cb7f8cb
--- /dev/null
+++ b/src/ast/loop_statement_test.cc

@@ -0,0 +1,168 @@
+// 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/loop_statement.h"
+
+#include <sstream>
+
+#include "gtest/gtest.h"
+#include "src/ast/kill_statement.h"
+#include "src/ast/if_statement.h"
+#include "src/ast/nop_statement.h"
+
+namespace tint {
+namespace ast {
+
+using LoopStatementTest = testing::Test;
+
+TEST_F(LoopStatementTest, Creation) {
+  std::vector<std::unique_ptr<Statement>> body;
+  body.push_back(std::make_unique<KillStatement>());
+  auto b_ptr = body[0].get();
+
+  std::vector<std::unique_ptr<Statement>> continuing;
+  continuing.push_back(std::make_unique<NopStatement>());
+  auto c_ptr = continuing[0].get();
+
+  LoopStatement l(std::move(body), std::move(continuing));
+  ASSERT_EQ(l.body().size(), 1);
+  EXPECT_EQ(l.body()[0].get(), b_ptr);
+  ASSERT_EQ(l.continuing().size(), 1);
+  EXPECT_EQ(l.continuing()[0].get(), c_ptr);
+}
+
+TEST_F(LoopStatementTest, Creation_WithSource) {
+  std::vector<std::unique_ptr<Statement>> body;
+  body.push_back(std::make_unique<KillStatement>());
+
+  std::vector<std::unique_ptr<Statement>> continuing;
+  continuing.push_back(std::make_unique<NopStatement>());
+
+  LoopStatement l(Source{20, 2}, std::move(body), std::move(continuing));
+  auto src = l.source();
+  EXPECT_EQ(src.line, 20);
+  EXPECT_EQ(src.column, 2);
+}
+
+TEST_F(LoopStatementTest, IsLoop) {
+  LoopStatement l;
+  EXPECT_TRUE(l.IsLoop());
+}
+
+TEST_F(LoopStatementTest, IsValid) {
+  std::vector<std::unique_ptr<Statement>> body;
+  body.push_back(std::make_unique<KillStatement>());
+
+  std::vector<std::unique_ptr<Statement>> continuing;
+  continuing.push_back(std::make_unique<NopStatement>());
+
+  LoopStatement l(std::move(body), std::move(continuing));
+  EXPECT_TRUE(l.IsValid());
+}
+
+TEST_F(LoopStatementTest, IsValid_WithoutContinuing) {
+  std::vector<std::unique_ptr<Statement>> body;
+  body.push_back(std::make_unique<KillStatement>());
+
+  LoopStatement l(std::move(body), {});
+  EXPECT_TRUE(l.IsValid());
+}
+
+TEST_F(LoopStatementTest, IsValid_WithoutBody) {
+  LoopStatement l({}, {});
+  EXPECT_TRUE(l.IsValid());
+}
+
+TEST_F(LoopStatementTest, IsValid_NullBodyStatement) {
+  std::vector<std::unique_ptr<Statement>> body;
+  body.push_back(std::make_unique<KillStatement>());
+  body.push_back(nullptr);
+
+  std::vector<std::unique_ptr<Statement>> continuing;
+  continuing.push_back(std::make_unique<NopStatement>());
+
+  LoopStatement l(std::move(body), std::move(continuing));
+  EXPECT_FALSE(l.IsValid());
+}
+
+TEST_F(LoopStatementTest, IsValid_InvalidBodyStatement) {
+  std::vector<std::unique_ptr<Statement>> body;
+  body.push_back(std::make_unique<KillStatement>());
+  body.push_back(std::make_unique<IfStatement>());
+
+  std::vector<std::unique_ptr<Statement>> continuing;
+  continuing.push_back(std::make_unique<NopStatement>());
+
+  LoopStatement l(std::move(body), std::move(continuing));
+  EXPECT_FALSE(l.IsValid());
+}
+
+TEST_F(LoopStatementTest, IsValid_NullContinuingStatement) {
+  std::vector<std::unique_ptr<Statement>> body;
+  body.push_back(std::make_unique<KillStatement>());
+
+  std::vector<std::unique_ptr<Statement>> continuing;
+  continuing.push_back(std::make_unique<NopStatement>());
+  continuing.push_back(nullptr);
+
+  LoopStatement l(std::move(body), std::move(continuing));
+  EXPECT_FALSE(l.IsValid());
+}
+
+TEST_F(LoopStatementTest, IsValid_InvalidContinuingStatement) {
+  std::vector<std::unique_ptr<Statement>> body;
+  body.push_back(std::make_unique<KillStatement>());
+
+  std::vector<std::unique_ptr<Statement>> continuing;
+  continuing.push_back(std::make_unique<NopStatement>());
+  continuing.push_back(std::make_unique<IfStatement>());
+
+  LoopStatement l(std::move(body), std::move(continuing));
+  EXPECT_FALSE(l.IsValid());
+}
+
+TEST_F(LoopStatementTest, ToStr) {
+  std::vector<std::unique_ptr<Statement>> body;
+  body.push_back(std::make_unique<KillStatement>());
+
+  LoopStatement l(std::move(body), {});
+  std::ostringstream out;
+  l.to_str(out, 2);
+  EXPECT_EQ(out.str(), R"(  Loop{
+    Kill{}
+  }
+)");
+}
+
+TEST_F(LoopStatementTest, ToStr_WithContinuing) {
+  std::vector<std::unique_ptr<Statement>> body;
+  body.push_back(std::make_unique<KillStatement>());
+
+  std::vector<std::unique_ptr<Statement>> continuing;
+  continuing.push_back(std::make_unique<NopStatement>());
+
+  LoopStatement l(std::move(body), std::move(continuing));
+  std::ostringstream out;
+  l.to_str(out, 2);
+  EXPECT_EQ(out.str(), R"(  Loop{
+    Kill{}
+    continuing {
+      Nop{}
+    }
+  }
+)");
+}
+
+}  // namespace ast
+}  // namespace tint