llvm-project/clang/test/Tooling/clang-diff-topdown.cpp

// RUN: %clang_cc1 -E %s > %t.src.cpp
// RUN: %clang_cc1 -E %s > %t.dst.cpp -DDEST
// RUN: clang-diff -dump-matches -stop-after=topdown %t.src.cpp %t.dst.cpp -- -std=c++11 | FileCheck %s
//
// Test the top-down matching of identical subtrees only.

#ifndef DEST

void f1()
{
  // Match some subtree of height greater than 2.
  // CHECK: Match CompoundStmt(3) to CompoundStmt(3)
  // CHECK: Match CompoundStmt(4) to CompoundStmt(4)
  // CHECK: Match NullStmt(5) to NullStmt(5)
  {{;}}

  // Don't match subtrees that are smaller.
  // CHECK-NOT: Match CompoundStmt(6)
  // CHECK-NOT: Match NullStmt(7)
  {;}

  // Greedy approach - use the first matching subtree when there are multiple
  // identical subtrees.
  // CHECK: Match CompoundStmt(8) to CompoundStmt(8)
  // CHECK: Match CompoundStmt(9) to CompoundStmt(9)
  // CHECK: Match NullStmt(10) to NullStmt(10)
  {{;;}}
}

#else

void f1() {

  {{;}}

  {;}

  {{;;}}
  // CHECK-NOT: Match {{.*}} to CompoundStmt(11)
  // CHECK-NOT: Match {{.*}} to CompoundStmt(12)
  // CHECK-NOT: Match {{.*}} to NullStmt(13)
  {{;;}}

  // CHECK-NOT: Match {{.*}} to NullStmt(14)
  ;
}

#endif