Recommit r274348 and r274349. The Windows failures should be fixed.

Original commit message:
"Add postorder traversal support to the RecursiveASTVisitor.

This feature needs to be explicitly enabled by overriding shouldTraversePostOrder()
as it has performance drawbacks for the iterative Stmt-traversal.

Patch by Raphael Isemann!

Reviewed by Richard Smith and Benjamin Kramer."


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@274830 91177308-0d34-0410-b5e6-96231b3b80d8

2 files changed, 124 insertions, 0 deletions

diff --git a/unittests/AST/CMakeLists.txt b/unittests/AST/CMakeLists.txt
index 7e9f320e94..a7008f3e7e 100644
--- a/unittests/AST/CMakeLists.txt
+++ b/unittests/AST/CMakeLists.txt
@@ -14,6 +14,7 @@ add_clang_unittest(ASTTests
   EvaluateAsRValueTest.cpp
   ExternalASTSourceTest.cpp
   NamedDeclPrinterTest.cpp
+  PostOrderASTVisitor.cpp
   SourceLocationTest.cpp
   StmtPrinterTest.cpp
   )
diff --git a/unittests/AST/PostOrderASTVisitor.cpp b/unittests/AST/PostOrderASTVisitor.cpp
new file mode 100644
index 0000000000..012f63a48a
--- /dev/null
+++ b/unittests/AST/PostOrderASTVisitor.cpp
@@ -0,0 +1,123 @@
+//===- unittests/AST/PostOrderASTVisitor.cpp - Declaration printer tests --===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file contains tests for the post-order traversing functionality
+// of RecursiveASTVisitor.
+//
+//===----------------------------------------------------------------------===//
+
+#include "clang/AST/RecursiveASTVisitor.h"
+#include "clang/Tooling/Tooling.h"
+#include "gtest/gtest.h"
+
+using namespace clang;
+
+namespace {
+
+  class RecordingVisitor
+    : public RecursiveASTVisitor<RecordingVisitor> {
+
+    bool VisitPostOrder;
+  public:
+    explicit RecordingVisitor(bool VisitPostOrder)
+      : VisitPostOrder(VisitPostOrder) {
+    }
+
+    // List of visited nodes during traversal.
+    std::vector<std::string> VisitedNodes;
+
+    bool shouldTraversePostOrder() const { return VisitPostOrder; }
+
+    bool VisitBinaryOperator(BinaryOperator *Op) {
+      VisitedNodes.push_back(Op->getOpcodeStr());
+      return true;
+    }
+
+    bool VisitIntegerLiteral(IntegerLiteral *Lit) {
+      VisitedNodes.push_back(Lit->getValue().toString(10, false));
+      return true;
+    }
+
+    bool VisitVarDecl(VarDecl* D) {
+      VisitedNodes.push_back(D->getNameAsString());
+      return true;
+    }
+
+    bool VisitCXXMethodDecl(CXXMethodDecl *D) {
+      VisitedNodes.push_back(D->getQualifiedNameAsString());
+      return true;
+    }
+
+    bool VisitReturnStmt(ReturnStmt *S) {
+      VisitedNodes.push_back("return");
+      return true;
+    }
+
+    bool VisitCXXRecordDecl(CXXRecordDecl *Declaration) {
+      VisitedNodes.push_back(Declaration->getQualifiedNameAsString());
+      return true;
+    }
+
+    bool VisitTemplateTypeParmType(TemplateTypeParmType *T) {
+      VisitedNodes.push_back(T->getDecl()->getQualifiedNameAsString());
+      return true;
+    }
+  };
+
+}
+
+TEST(RecursiveASTVisitor, PostOrderTraversal) {
+  auto ASTUnit = tooling::buildASTFromCode(
+    "class A {"
+    "  class B {"
+    "    int foo() { while(4) { int i = 9; } return (1 + 3) + 2; }"
+    "  };"
+    "};"
+  );
+  auto TU = ASTUnit->getASTContext().getTranslationUnitDecl();
+  // We traverse the translation unit and store all
+  // visited nodes.
+  RecordingVisitor Visitor(true);
+  Visitor.TraverseTranslationUnitDecl(TU);
+
+  std::vector<std::string> expected = {
+    "4", "9", "i", "1", "3", "+", "2", "+", "return", "A::B::foo", "A::B", "A"
+  };
+  // Compare the list of actually visited nodes
+  // with the expected list of visited nodes.
+  ASSERT_EQ(expected.size(), Visitor.VisitedNodes.size());
+  for (std::size_t I = 0; I < expected.size(); I++) {
+    ASSERT_EQ(expected[I], Visitor.VisitedNodes[I]);
+  }
+}
+
+TEST(RecursiveASTVisitor, NoPostOrderTraversal) {
+  auto ASTUnit = tooling::buildASTFromCode(
+    "class A {"
+    "  class B {"
+    "    int foo() { return 1 + 2; }"
+    "  };"
+    "};"
+  );
+  auto TU = ASTUnit->getASTContext().getTranslationUnitDecl();
+  // We traverse the translation unit and store all
+  // visited nodes.
+  RecordingVisitor Visitor(false);
+  Visitor.TraverseTranslationUnitDecl(TU);
+
+  std::vector<std::string> expected = {
+    "A", "A::B", "A::B::foo", "return", "+", "1", "2"
+  };
+  // Compare the list of actually visited nodes
+  // with the expected list of visited nodes.
+  ASSERT_EQ(expected.size(), Visitor.VisitedNodes.size());
+  for (std::size_t I = 0; I < expected.size(); I++) {
+    ASSERT_EQ(expected[I], Visitor.VisitedNodes[I]);
+  }
+}