From: Daniel Jasper <djasper@google.com>
Date: Fri, 21 Mar 2014 13:43:14 +0000 (+0000)
Subject: clang-format: Add flag for removing empty lines at the start of blocks.
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=b6e55caa1d10e2292cbb953a1934e91a3511b084;p=clang

clang-format: Add flag for removing empty lines at the start of blocks.

This unbreaks polly-formatting-tests and we can make a decision for
LLVM style independently.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@204467 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/include/clang/Format/Format.h b/include/clang/Format/Format.h
index c322f552d1..fd180f4671 100644
--- a/include/clang/Format/Format.h
+++ b/include/clang/Format/Format.h
@@ -58,6 +58,9 @@ struct FormatStyle {
   /// \brief The maximum number of consecutive empty lines to keep.
   unsigned MaxEmptyLinesToKeep;
 
+  /// \brief If true, empty lines at the start of blocks are kept.
+  bool KeepEmptyLinesAtTheStartOfBlocks;
+
   /// \brief The penalty for each line break introduced inside a comment.
   unsigned PenaltyBreakComment;
 
@@ -333,6 +336,8 @@ struct FormatStyle {
                R.IndentFunctionDeclarationAfterType &&
            IndentWidth == R.IndentWidth && Language == R.Language &&
            MaxEmptyLinesToKeep == R.MaxEmptyLinesToKeep &&
+           KeepEmptyLinesAtTheStartOfBlocks ==
+               R.KeepEmptyLinesAtTheStartOfBlocks &&
            NamespaceIndentation == R.NamespaceIndentation &&
            ObjCSpaceAfterProperty == R.ObjCSpaceAfterProperty &&
            ObjCSpaceBeforeProtocolList == R.ObjCSpaceBeforeProtocolList &&
diff --git a/lib/Format/Format.cpp b/lib/Format/Format.cpp
index 976b546681..b810f4492e 100644
--- a/lib/Format/Format.cpp
+++ b/lib/Format/Format.cpp
@@ -163,6 +163,8 @@ template <> struct MappingTraits<FormatStyle> {
                    Style.ExperimentalAutoDetectBinPacking);
     IO.mapOptional("IndentCaseLabels", Style.IndentCaseLabels);
     IO.mapOptional("MaxEmptyLinesToKeep", Style.MaxEmptyLinesToKeep);
+    IO.mapOptional("KeepEmptyLinesAtTheStartOfBlocks",
+                   Style.KeepEmptyLinesAtTheStartOfBlocks);
     IO.mapOptional("NamespaceIndentation", Style.NamespaceIndentation);
     IO.mapOptional("ObjCSpaceAfterProperty", Style.ObjCSpaceAfterProperty);
     IO.mapOptional("ObjCSpaceBeforeProtocolList",
@@ -267,6 +269,7 @@ FormatStyle getLLVMStyle() {
   LLVMStyle.IndentWidth = 2;
   LLVMStyle.TabWidth = 8;
   LLVMStyle.MaxEmptyLinesToKeep = 1;
+  LLVMStyle.KeepEmptyLinesAtTheStartOfBlocks = true;
   LLVMStyle.NamespaceIndentation = FormatStyle::NI_None;
   LLVMStyle.ObjCSpaceAfterProperty = false;
   LLVMStyle.ObjCSpaceBeforeProtocolList = true;
@@ -308,6 +311,7 @@ FormatStyle getGoogleStyle(FormatStyle::LanguageKind Language) {
   GoogleStyle.DerivePointerBinding = true;
   GoogleStyle.IndentCaseLabels = true;
   GoogleStyle.IndentFunctionDeclarationAfterType = true;
+  GoogleStyle.KeepEmptyLinesAtTheStartOfBlocks = false;
   GoogleStyle.ObjCSpaceAfterProperty = false;
   GoogleStyle.ObjCSpaceBeforeProtocolList = false;
   GoogleStyle.PointerBindsToType = true;
@@ -889,7 +893,8 @@ private:
       Newlines = 1;
 
     // Remove empty lines after "{".
-    if (PreviousLine && PreviousLine->Last->is(tok::l_brace) &&
+    if (!Style.KeepEmptyLinesAtTheStartOfBlocks && PreviousLine &&
+        PreviousLine->Last->is(tok::l_brace) &&
         PreviousLine->First->isNot(tok::kw_namespace))
       Newlines = 1;
 
diff --git a/unittests/Format/FormatTest.cpp b/unittests/Format/FormatTest.cpp
index dafaac4569..0ae08bcfc0 100644
--- a/unittests/Format/FormatTest.cpp
+++ b/unittests/Format/FormatTest.cpp
@@ -182,11 +182,14 @@ TEST_F(FormatTest, RemovesEmptyLines) {
             format("namespace N {\n"
                    "\n"
                    "int    i;\n"
-                   "}"));
+                   "}",
+                   getGoogleStyle()));
 
   // Remove empty lines at the beginning and end of blocks.
   EXPECT_EQ("void f() {\n"
+            "\n"
             "  if (a) {\n"
+            "\n"
             "    f();\n"
             "  }\n"
             "}",
@@ -198,7 +201,23 @@ TEST_F(FormatTest, RemovesEmptyLines) {
                    "\n"
                    "  }\n"
                    "\n"
-                   "}"));
+                   "}",
+                   getLLVMStyle()));
+  EXPECT_EQ("void f() {\n"
+            "  if (a) {\n"
+            "    f();\n"
+            "  }\n"
+            "}",
+            format("void f() {\n"
+                   "\n"
+                   "  if (a) {\n"
+                   "\n"
+                   "    f();\n"
+                   "\n"
+                   "  }\n"
+                   "\n"
+                   "}",
+                   getGoogleStyle()));
 
   // Don't remove empty lines in more complex control statements.
   EXPECT_EQ("void f() {\n"
@@ -7490,6 +7509,7 @@ TEST_F(FormatTest, ParsesConfiguration) {
   CHECK_PARSE_BOOL(ConstructorInitializerAllOnOneLineOrOnePerLine);
   CHECK_PARSE_BOOL(DerivePointerBinding);
   CHECK_PARSE_BOOL(IndentCaseLabels);
+  CHECK_PARSE_BOOL(KeepEmptyLinesAtTheStartOfBlocks);
   CHECK_PARSE_BOOL(ObjCSpaceAfterProperty);
   CHECK_PARSE_BOOL(ObjCSpaceBeforeProtocolList);
   CHECK_PARSE_BOOL(PointerBindsToType);