Don't try to align builder-type continuations on assignments.

Before:
int aaaa = aaaaa().aaaaa() // force break
           .aaaaa();
After:
int aaaa = aaaaa().aaaaa() // force break
    .aaaaa();

The other indent is just wrong and confusing.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@173273 91177308-0d34-0410-b5e6-96231b3b80d8

lib/Format/Format.cpp

@@ -421,9 +421,9 @@ private:
 
   struct ParenState {
     ParenState(unsigned Indent, unsigned LastSpace)
-        : Indent(Indent), LastSpace(LastSpace), FirstLessLess(0),
-          BreakBeforeClosingBrace(false), BreakAfterComma(false),
-          HasMultiParameterLine(false) {}
+        : Indent(Indent), LastSpace(LastSpace), AssignmentColumn(0),
+          FirstLessLess(0), BreakBeforeClosingBrace(false),
+          BreakAfterComma(false), HasMultiParameterLine(false) {}
 
     /// \brief The position to which a specific parenthesis level needs to be
     /// indented.
@@ -436,6 +436,9 @@ private:
     ///                             OtherParameter));
     unsigned LastSpace;
 
+    /// \brief This is the column of the first token after an assignment.
+    unsigned AssignmentColumn;
+
     /// \brief The position the first "<<" operator encountered on each level.
     ///
     /// Used to align "<<" operators. 0 if no such operator has been encountered
@@ -457,6 +460,8 @@ private:
         return Indent < Other.Indent;
       if (LastSpace != Other.LastSpace)
         return LastSpace < Other.LastSpace;
+      if (AssignmentColumn != Other.AssignmentColumn)
+        return AssignmentColumn < Other.AssignmentColumn;
       if (FirstLessLess != Other.FirstLessLess)
         return FirstLessLess < Other.FirstLessLess;
       if (BreakBeforeClosingBrace != Other.BreakBeforeClosingBrace)
@@ -547,6 +552,9 @@ private:
         State.Column = State.ForLoopVariablePos;
       } else if (State.NextToken->Parent->ClosesTemplateDeclaration) {
         State.Column = State.Stack[ParenLevel].Indent - 4;
+      } else if (Previous.Type == TT_BinaryOperator &&
+                 State.Stack.back().AssignmentColumn != 0) {
+        State.Column = State.Stack.back().AssignmentColumn;
       } else {
         State.Column = State.Stack[ParenLevel].Indent;
       }
@@ -587,7 +595,7 @@ private:
       if (RootToken.isNot(tok::kw_for) && ParenLevel == 0 &&
           (getPrecedence(Previous) == prec::Assignment ||
            Previous.is(tok::kw_return)))
-        State.Stack[ParenLevel].Indent = State.Column + Spaces;
+        State.Stack.back().AssignmentColumn = State.Column + Spaces;
       if (Previous.is(tok::l_paren) || Previous.is(tok::l_brace) ||
           State.NextToken->Parent->Type == TT_TemplateOpener)
         State.Stack[ParenLevel].Indent = State.Column + Spaces;

unittests/Format/FormatTest.cpp

@@ -1006,10 +1006,10 @@ TEST_F(FormatTest, FormatsOneParameterPerLineIfNecessary) {
 TEST_F(FormatTest, FormatsBuilderPattern) {
   verifyFormat(
       "return llvm::StringSwitch<Reference::Kind>(name)\n"
-      "       .StartsWith(\".eh_frame_hdr\", ORDER_EH_FRAMEHDR)\n"
-      "       .StartsWith(\".eh_frame\", ORDER_EH_FRAME).StartsWith(\".init\", ORDER_INIT)\n"
-      "       .StartsWith(\".fini\", ORDER_FINI).StartsWith(\".hash\", ORDER_HASH)\n"
-      "       .Default(ORDER_TEXT);\n");
+      "    .StartsWith(\".eh_frame_hdr\", ORDER_EH_FRAMEHDR)\n"
+      "    .StartsWith(\".eh_frame\", ORDER_EH_FRAME).StartsWith(\".init\", ORDER_INIT)\n"
+      "    .StartsWith(\".fini\", ORDER_FINI).StartsWith(\".hash\", ORDER_HASH)\n"
+      "    .Default(ORDER_TEXT);\n");
 }
 
 TEST_F(FormatTest, DoesNotBreakTrailingAnnotation) {
@@ -1042,6 +1042,10 @@ TEST_F(FormatTest, BreaksAfterAssignments) {
   verifyFormat(
       "CharSourceRange LineRange = CharSourceRange::getTokenRange(\n"
       "    Line.Tokens.front().Tok.getLo(), Line.Tokens.back().Tok.getLoc());");
+
+  verifyFormat(
+      "aaaaaaaaaaaaaaaaaaaaaaaaaa aaaa = aaaaaaaaaaaaaa(0).aaaa()\n"
+      "    .aaaaaaaaaaaa(aaaaaaaaaaaaaaaaaaa::aaaaaaaaaaaaaaaaaaaaa);");
 }
 
 TEST_F(FormatTest, AlignsAfterAssignments) {