Tooling: Ignore file names in tooling::deduplicate.

This was horribly broken due to how the sort predicate works. We would
report a conflict for files with a replacement in the same position but
different names if the length differed. Just ignore paths as this is often
what the user wants. Files can occur with different names (due to symlinks
or relative paths) and we don't ever want to do the same edit in one file
twice.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@217439 91177308-0d34-0410-b5e6-96231b3b80d8

include/clang/Tooling/Refactoring.h

@@ -171,7 +171,7 @@ unsigned shiftedCodePosition(const std::vector<Replacement> &Replaces,
                              unsigned Position);
 
 /// \brief Removes duplicate Replacements and reports if Replacements conflict
-/// with one another.
+/// with one another. All Replacements are assumed to be in the same file.
 ///
 /// \post Replaces[i].getOffset() <= Replaces[i+1].getOffset().
 ///

lib/Tooling/Refactoring.cpp

@@ -238,11 +238,25 @@ void deduplicate(std::vector<Replacement> &Replaces,
   if (Replaces.empty())
     return;
 
-  // Deduplicate
-  std::sort(Replaces.begin(), Replaces.end());
-  std::vector<Replacement>::iterator End =
-      std::unique(Replaces.begin(), Replaces.end());
-  Replaces.erase(End, Replaces.end());
+  auto LessNoPath = [](const Replacement &LHS, const Replacement &RHS) {
+    if (LHS.getOffset() != RHS.getOffset())
+      return LHS.getOffset() < RHS.getOffset();
+    if (LHS.getLength() != RHS.getLength())
+      return LHS.getLength() < RHS.getLength();
+    return LHS.getReplacementText() < RHS.getReplacementText();
+  };
+
+  auto EqualNoPath = [](const Replacement &LHS, const Replacement &RHS) {
+    return LHS.getOffset() == RHS.getOffset() &&
+           LHS.getLength() == RHS.getLength() &&
+           LHS.getReplacementText() == RHS.getReplacementText();
+  };
+
+  // Deduplicate. We don't want to deduplicate based on the path as we assume
+  // that all replacements refer to the same file (or are symlinks).
+  std::sort(Replaces.begin(), Replaces.end(), LessNoPath);
+  Replaces.erase(std::unique(Replaces.begin(), Replaces.end(), EqualNoPath),
+                 Replaces.end());
 
   // Detect conflicts
   Range ConflictRange(Replaces.front().getOffset(),

unittests/Tooling/RefactoringTest.cpp

@@ -393,6 +393,8 @@ TEST(DeduplicateTest, removesDuplicates) {
   Input.push_back(Replacement("fileA", 50, 0, " foo ")); // Duplicate
   Input.push_back(Replacement("fileA", 51, 3, " bar "));
   Input.push_back(Replacement("fileB", 51, 3, " bar ")); // Filename differs!
+  Input.push_back(Replacement("fileB", 60, 1, " bar "));
+  Input.push_back(Replacement("fileA", 60, 2, " bar "));
   Input.push_back(Replacement("fileA", 51, 3, " moo ")); // Replacement text
                                                          // differs!
 
@@ -403,12 +405,14 @@ TEST(DeduplicateTest, removesDuplicates) {
   Expected.push_back(Replacement("fileA", 50, 0, " foo "));
   Expected.push_back(Replacement("fileA", 51, 3, " bar "));
   Expected.push_back(Replacement("fileA", 51, 3, " moo "));
-  Expected.push_back(Replacement("fileB", 51, 3, " bar "));
+  Expected.push_back(Replacement("fileB", 60, 1, " bar "));
+  Expected.push_back(Replacement("fileA", 60, 2, " bar "));
 
   std::vector<Range> Conflicts; // Ignored for this test
   deduplicate(Input, Conflicts);
 
-  ASSERT_TRUE(Expected == Input);
+  EXPECT_EQ(3U, Conflicts.size());
+  EXPECT_EQ(Expected, Input);
 }
 
 TEST(DeduplicateTest, detectsConflicts) {