Reformat lines if they were "moved around".

An unwrapped line can get moved around if there is no newline before
it and the previous line was formatted.

Example:

  template<typename T>  // Cursor is on this line when hitting "format"
  T *getFETokenInfo() const { return static_cast<T*>(FETokenInfo); }

"return .." is the second unwrapped line in this scenario. I does not
touch any reformatted region. Thus, the result of formatting is:

  template <typename T> T *getFETokenInfo() const { return static_cast<T *>(FETokenInfo); }

After second format (and arguably desired end-result):

  template <typename T> T *getFETokenInfo() const {
      return static_cast<T *>(FETokenInfo);
  }

This fixes: llvm.org/PR15060.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@175440 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/unittests/Format/FormatTest.cpp b/unittests/Format/FormatTest.cpp
index c63d756..90196af 100644
--- a/unittests/Format/FormatTest.cpp
+++ b/unittests/Format/FormatTest.cpp
@@ -168,6 +168,19 @@
   EXPECT_EQ("int a;\nint b;", format("int a; \nint b;", 0, 0, getLLVMStyle()));
 }
 
+TEST_F(FormatTest, ReformatsMovedLines) {
+  EXPECT_EQ(
+      "template <typename T> T *getFETokenInfo() const {\n"
+      "  return static_cast<T *>(FETokenInfo);\n"
+      "}\n"
+      "  int a; // <- Should not be formatted",
+      format(
+          "template<typename T>\n"
+          "T *getFETokenInfo() const { return static_cast<T*>(FETokenInfo); }\n"
+          "  int a; // <- Should not be formatted",
+          9, 5, getLLVMStyle()));
+}
+
 //===----------------------------------------------------------------------===//
 // Tests for control statements.
 //===----------------------------------------------------------------------===//