Several improvements to the formatting of static initializers.

1. Never avoid bin packing in static initializers as this can
   lead to terrible results.
2. If an element has to be broken over multiple lines, break after
   the following comma.

This should be a step forward, but there are still many cases
especially with nested static initializers that we handle badly.
More patches will follow.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@174061 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Format/Format.cpp b/lib/Format/Format.cpp
index 08ea8e97de5db9996123bb54c9850efc139ff4ca..2a606974e5a9913ea2e0f121be06f8fbe83414ff 100644 (file)
--- a/lib/Format/Format.cpp
+++ b/lib/Format/Format.cpp
@@ -229,7 +229,8 @@ public:
     LineState State;
     State.Column = FirstIndent;
     State.NextToken = &RootToken;
-    State.Stack.push_back(ParenState(FirstIndent + 4, FirstIndent));
+    State.Stack.push_back(ParenState(FirstIndent + 4, FirstIndent,
+                                     !Style.BinPackParameters));
     State.VariablePos = 0;
     State.LineContainsContinuedForLoopSection = false;
 
@@ -298,10 +299,11 @@ private:
   }
 
   struct ParenState {
-    ParenState(unsigned Indent, unsigned LastSpace)
+    ParenState(unsigned Indent, unsigned LastSpace, bool AvoidBinPacking)
         : Indent(Indent), LastSpace(LastSpace), AssignmentColumn(0),
           FirstLessLess(0), BreakBeforeClosingBrace(false), QuestionColumn(0),
-          BreakAfterComma(false), HasMultiParameterLine(false) {
+          AvoidBinPacking(AvoidBinPacking), BreakAfterComma(false),
+          HasMultiParameterLine(false) {
     }
 
     /// \brief The position to which a specific parenthesis level needs to be
@@ -334,7 +336,15 @@ private:
     /// \brief The column of a \c ? in a conditional expression;
     unsigned QuestionColumn;
 
+    /// \brief Avoid bin packing, i.e. multiple parameters/elements on multiple
+    /// lines, in this context.
+    bool AvoidBinPacking;
+
+    /// \brief Break after the next comma (or all the commas in this context if
+    /// \c AvoidBinPacking is \c true).
     bool BreakAfterComma;
+
+    /// \brief This context already has a line with more than one parameter.
     bool HasMultiParameterLine;
 
     bool operator<(const ParenState &Other) const {
@@ -350,6 +360,8 @@ private:
         return BreakBeforeClosingBrace;
       if (QuestionColumn != Other.QuestionColumn)
         return QuestionColumn < Other.QuestionColumn;
+      if (AvoidBinPacking != Other.AvoidBinPacking)
+        return AvoidBinPacking;
       if (BreakAfterComma != Other.BreakAfterComma)
         return BreakAfterComma;
       if (HasMultiParameterLine != Other.HasMultiParameterLine)
@@ -444,6 +456,9 @@ private:
         State.Column = State.Stack[ParenLevel].Indent;
       }
 
+      if (Previous.is(tok::comma) && !State.Stack.back().AvoidBinPacking)
+        State.Stack.back().BreakAfterComma = false;
+
       if (RootToken.is(tok::kw_for))
         State.LineContainsContinuedForLoopSection = Previous.isNot(tok::semi);
 
@@ -499,6 +514,7 @@ private:
         State.Stack.back().LastSpace = State.Column;
       else if (Previous.ParameterCount > 1 &&
                (Previous.is(tok::l_paren) || Previous.is(tok::l_square) ||
+                Previous.is(tok::l_brace) ||
                 Previous.Type == TT_TemplateOpener))
         // If this function has multiple parameters, indent nested calls from
         // the start of the first parameter.
@@ -509,7 +525,7 @@ private:
     if (Newline && Previous.is(tok::l_brace))
       State.Stack.back().BreakBeforeClosingBrace = true;
 
-    if (!Style.BinPackParameters && Newline) {
+    if (State.Stack.back().AvoidBinPacking && Newline) {
       // If we are breaking after '(', '{', '<', this is not bin packing unless
       // AllowAllParametersOfDeclarationOnNextLine is false.
       if ((Previous.isNot(tok::l_paren) && Previous.isNot(tok::l_brace) &&
@@ -538,6 +554,17 @@ private:
       State.Stack.back().FirstLessLess = State.Column;
     if (Current.is(tok::question))
       State.Stack.back().QuestionColumn = State.Column;
+    if (Current.is(tok::l_brace) && Current.MatchingParen != NULL &&
+        Current.Children[0].isNot(tok::l_brace) &&
+        !Current.MatchingParen->MustBreakBefore) {
+      AnnotatedToken *End = Current.MatchingParen;
+      while (!End->Children.empty() && !End->Children[0].CanBreakBefore) {
+        End = &End->Children[0];
+      }
+      unsigned Length = End->TotalLength - Current.TotalLength + 1;
+      if (Length + State.Column > getColumnLimit())
+        State.Stack.back().BreakAfterComma = true;
+    }
 
     // If we encounter an opening (, [, { or <, we add a level to our stacks to
     // prepare for the following tokens.
@@ -545,16 +572,16 @@ private:
         Current.is(tok::l_brace) ||
         State.NextToken->Type == TT_TemplateOpener) {
       unsigned NewIndent;
+      bool AvoidBinPacking;
       if (Current.is(tok::l_brace)) {
-        // FIXME: This does not work with nested static initializers.
-        // Implement a better handling for static initializers and similar
-        // constructs.
-        NewIndent = Line.Level * 2 + 2;
+        NewIndent = 2 + State.Stack.back().LastSpace;
+        AvoidBinPacking = false;
       } else {
         NewIndent = 4 + State.Stack.back().LastSpace;
+        AvoidBinPacking = !Style.BinPackParameters;
       }
-      State.Stack.push_back(ParenState(NewIndent,
-                                       State.Stack.back().LastSpace));
+      State.Stack.push_back(ParenState(NewIndent, State.Stack.back().LastSpace,
+                                       AvoidBinPacking));
     }
 
     // If we encounter a closing ), ], } or >, we can remove a level from our
@@ -611,7 +638,8 @@ private:
     // Trying to insert a parameter on a new line if there are already more than
     // one parameter on the current line is bin packing.
     if (NewLine && State.NextToken->Parent->is(tok::comma) &&
-        State.Stack.back().HasMultiParameterLine && !Style.BinPackParameters)
+        State.Stack.back().HasMultiParameterLine &&
+        State.Stack.back().AvoidBinPacking)
       return UINT_MAX;
     if (!NewLine && (State.NextToken->Type == TT_CtorInitializerColon ||
                      (State.NextToken->Parent->ClosesTemplateDeclaration &&

diff --git a/lib/Format/TokenAnnotator.cpp b/lib/Format/TokenAnnotator.cpp
index eabc8cff285bcf6fd8d92d04ffcce6671d3f798f..ecc9b4e468a44bf8df90537f9423d3bd8cadaf1a 100644 (file)
--- a/lib/Format/TokenAnnotator.cpp
+++ b/lib/Format/TokenAnnotator.cpp
@@ -206,6 +206,8 @@ public:
       }
       if (CurrentToken->is(tok::r_paren) || CurrentToken->is(tok::r_square))
         return false;
+      if (CurrentToken->is(tok::comma))
+        ++Left->ParameterCount;
       if (!consumeToken())
         return false;
     }

diff --git a/unittests/Format/FormatTest.cpp b/unittests/Format/FormatTest.cpp
index 97358982cf60d4b10114c87348565fb12bee1104..5ffd3518891c3d181016e790454015f024d74935 100644 (file)
--- a/unittests/Format/FormatTest.cpp
+++ b/unittests/Format/FormatTest.cpp
@@ -506,13 +506,20 @@ TEST_F(FormatTest, CommentsInStaticInitializers) {
                "                         bbbbbbbbbbb, ccccccccccc };");
   verifyGoogleFormat(
       "static SomeType type = { aaaaaaaaaaa,  // comment for aa...\n"
-      "                         bbbbbbbbbbb,\n"
-      "                         ccccccccccc };");
+      "                         bbbbbbbbbbb, ccccccccccc };");
   verifyGoogleFormat("static SomeType type = { aaaaaaaaaaa,\n"
                      "                         // comment for bb....\n"
-                     "                         bbbbbbbbbbb,\n"
-                     "                         ccccccccccc };");
+                     "                         bbbbbbbbbbb, ccccccccccc };");
 
+  verifyFormat("S s = { { a, b, c },   // Group #1\n"
+               "        { d, e, f },   // Group #2\n"
+               "        { g, h, i } }; // Group #3");
+  verifyFormat("S s = { { // Group #1\n"
+               "          a, b, c },\n"
+               "        { // Group #2\n"
+               "          d, e, f },\n"
+               "        { // Group #3\n"
+               "          g, h, i } };");
 }
 
 //===----------------------------------------------------------------------===//
@@ -649,6 +656,12 @@ TEST_F(FormatTest, StaticInitializers) {
       "static SomeClass = { a, b, c, d, e, f, g, h, i, j,\n"
       "                     looooooooooooooooooooooooooooooooooongname,\n"
       "                     looooooooooooooooooooooooooooooong };");
+  // Allow bin-packing in static initializers as this would often lead to
+  // terrible results, e.g.:
+  verifyGoogleFormat(
+      "static SomeClass = { a, b, c, d, e, f, g, h, i, j,\n"
+      "                     looooooooooooooooooooooooooooooooooongname,\n"
+      "                     looooooooooooooooooooooooooooooong };");
 }
 
 TEST_F(FormatTest, NestedStaticInitializers) {
@@ -657,7 +670,12 @@ TEST_F(FormatTest, NestedStaticInitializers) {
       "static A x = { { { init1, init2, init3, init4 },\n"
       "                 { init1, init2, init3, init4 } } };");
 
-  // FIXME: Fix this in general and verify that it works in LLVM style again.
+  verifyFormat(
+      "somes Status::global_reps[3] = {\n"
+      "  { kGlobalRef, OK_CODE, NULL, NULL, NULL },\n"
+      "  { kGlobalRef, CANCELLED_CODE, NULL, NULL, NULL },\n"
+      "  { kGlobalRef, UNKNOWN_CODE, NULL, NULL, NULL }\n"
+      "};");
   verifyGoogleFormat(
       "somes Status::global_reps[3] = {\n"
       "  { kGlobalRef, OK_CODE, NULL, NULL, NULL },\n"
@@ -669,6 +687,13 @@ TEST_F(FormatTest, NestedStaticInitializers) {
       "                   { rect.fRight - rect.fLeft, rect.fBottom - rect.fTop"
       " } };");
 
+  verifyFormat(
+      "SomeArrayOfSomeType a = { { { 1, 2, 3 }, { 1, 2, 3 },\n"
+      "                            { 111111111111111111111111111111,\n"
+      "                              222222222222222222222222222222,\n"
+      "                              333333333333333333333333333333 },\n"
+      "                            { 1, 2, 3 }, { 1, 2, 3 } } };");
+
   // FIXME: We might at some point want to handle this similar to parameter
   // lists, where we have an option to put each on a single line.
   verifyFormat("struct {\n"