clang-format: Format line if invoked on the trailing newline.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@220883 91177308-0d34-0410-b5e6-96231b3b80d8

lib/Format/Format.cpp

@@ -1962,8 +1962,7 @@ private:
     if (!IncludeLeadingNewlines)
       Start = Start.getLocWithOffset(First.LastNewlineOffset);
     SourceLocation End = Last.getStartOfNonWhitespace();
-    if (Last.TokenText.size() > 0)
-      End = End.getLocWithOffset(Last.TokenText.size() - 1);
+    End = End.getLocWithOffset(Last.TokenText.size());
     CharSourceRange Range = CharSourceRange::getCharRange(Start, End);
     return affectsCharSourceRange(Range);
   }

unittests/Format/FormatTest.cpp

@@ -159,9 +159,21 @@ TEST_F(FormatTest, FormatsCorrectRegionForLeadingWhitespace) {
                    25, 0, getLLVMStyleWithColumns(12)));
 }
 
+TEST_F(FormatTest, FormatLineWhenInvokedOnTrailingNewline) {
+  EXPECT_EQ("int  b;\n\nint a;",
+            format("int  b;\n\nint a;", 8, 0, getLLVMStyle()));
+  EXPECT_EQ("int b;\n\nint a;",
+            format("int  b;\n\nint a;", 7, 0, getLLVMStyle()));
+
+  // This might not strictly be correct, but is likely good in all practical
+  // cases.
+  EXPECT_EQ("int b;\nint a;",
+            format("int  b;int a;", 7, 0, getLLVMStyle()));
+}
+
 TEST_F(FormatTest, RemovesWhitespaceWhenTriggeredOnEmptyLine) {
   EXPECT_EQ("int  a;\n\n int b;",
-            format("int  a;\n  \n\n int b;", 7, 0, getLLVMStyle()));
+            format("int  a;\n  \n\n int b;", 8, 0, getLLVMStyle()));
   EXPECT_EQ("int  a;\n\n int b;",
             format("int  a;\n  \n\n int b;", 9, 0, getLLVMStyle()));
 }