Fix a bug that would lead to bad line break decisions in for loops.

Before:
    for (aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa aaaaaaaaaaa = aaaaaaaaaaaaaaa
             .aaaaaaaaaaaaaaaa;
         aaaaaaaaaaa != aaaaaaaaaaaaaaaaaaa; ++aaaaaaaaaaa) {}

After:
    for (aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa aaaaaaaaaaa =
             aaaaaaaaaaaaaaa.aaaaaaaaaaaaaaaa;
         aaaaaaaaaaa != aaaaaaaaaaaaaaaaaaa; ++aaaaaaaaaaa) {}

llvm-svn: 173695

2 files changed, 18 insertions, 6 deletions

diff --git a/clang/lib/Format/Format.cpp b/clang/lib/Format/Format.cpp
index 21997817354..8eebda0740b 100644
--- a/clang/lib/Format/Format.cpp
+++ b/clang/lib/Format/Format.cpp
@@ -723,6 +723,12 @@ private:
     if (Left.Type == TT_RangeBasedForLoopColon)
       return 5;
 
+    if (Right.is(tok::arrow) || Right.is(tok::period)) {
+      if (Left.is(tok::r_paren) && Line.Type == LT_BuilderTypeCall)
+        return 5; // Should be smaller than breaking at a nested comma.
+      return 150;
+    }
+
     // In for-loops, prefer breaking at ',' and ';'.
     if (RootToken.is(tok::kw_for) &&
         (Left.isNot(tok::comma) && Left.isNot(tok::semi)))
@@ -753,12 +759,6 @@ private:
     if (Level != prec::Unknown)
       return Level;
 
-    if (Right.is(tok::arrow) || Right.is(tok::period)) {
-      if (Left.is(tok::r_paren) && Line.Type == LT_BuilderTypeCall)
-        return 5; // Should be smaller than breaking at a nested comma.
-      return 150;
-    }
-
     return 3;
   }
 
diff --git a/clang/unittests/Format/FormatTest.cpp b/clang/unittests/Format/FormatTest.cpp
index bdc5f9a5c55..63110bbfbe0 100644
--- a/clang/unittests/Format/FormatTest.cpp
+++ b/clang/unittests/Format/FormatTest.cpp
@@ -239,6 +239,18 @@ TEST_F(FormatTest, FormatsForLoop) {
   verifyFormat(
       "for (MachineFun::iterator IIII = PrevIt, EEEE = F.end(); IIII != EEEE;\n"
       "     ++IIIII) {\n}");
+  verifyFormat(
+      "for (aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa aaaaaaaaaaa =\n"
+      "         aaaaaaaaaaaaaaaa.aaaaaaaaaaaaaaa;\n"
+      "     aaaaaaaaaaa != aaaaaaaaaaaaaaaaaaa; ++aaaaaaaaaaa) {\n}");
+
+  // FIXME: Not sure whether we want extra identation in line 3 here:
+  verifyFormat(
+      "for (aaaaaaaaaaaaaaaaa aaaaaaaaaaa = aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa;\n"
+      "     aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa !=\n"
+      "     aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa(\n"
+      "         aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa);\n"
+      "     ++aaaaaaaaaaa) {\n}");
 }
 
 TEST_F(FormatTest, RangeBasedForLoops) {