[PATCH] Fix bug in clang-format while merging short function (PR19461)

[Daniel Jasper]

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Comment at: lib/Format/Format.cpp:641
@@ -640,2 +640,3 @@
     AnnotatedLine &Line = **I;
-    if (Line.First->isOneOf(tok::kw_if, tok::kw_while, tok::kw_do, tok::r_brace,
+    if (Line.First->MustBreakBefore ||
+        Line.First->isOneOf(tok::kw_if, tok::kw_while, tok::kw_do, tok::r_brace,
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Why would it be a problem if we need to wrap before the first of the lines we are going to join. I think the test case passes for the wrong reason. Of course MustBreakBefore is set for the first token of:

"void foo().."

But that is not the point. We are actually interested at whether there is any token other than the first where MustBreakBefore is set (the "{" in the case of the test).

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Comment at: lib/Format/Format.cpp:664
@@ +663,3 @@
+      // allows merging
+      if (I[1]->First->MustBreakBefore || I[2]->First->MustBreakBefore)
+        return 0;
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How about we put this check into "nextTwoLinesFitInto"?

http://reviews.llvm.org/D3439