[clang] 829ed96 - Reland [clang-format] Add the KeepEmptyLinesAtEOF option

[Owen Pan via cfe-commits]

Author: Owen Pan
Date: 2023-06-13T10:02:10-07:00
New Revision: 829ed96b779c10cb023d7e3dbcfad22413979ec4

URL: https://github.com/llvm/llvm-project/commit/829ed96b779c10cb023d7e3dbcfad22413979ec4
DIFF: https://github.com/llvm/llvm-project/commit/829ed96b779c10cb023d7e3dbcfad22413979ec4.diff

LOG: Reland [clang-format] Add the KeepEmptyLinesAtEOF option

Added: 
    

Modified: 
    clang/docs/ClangFormatStyleOptions.rst
    clang/docs/ReleaseNotes.rst
    clang/include/clang/Format/Format.h
    clang/lib/Format/Format.cpp
    clang/lib/Format/UnwrappedLineFormatter.cpp
    clang/unittests/Format/ConfigParseTest.cpp
    clang/unittests/Format/FormatTest.cpp

Removed: 
    


################################################################################
diff  --git a/clang/docs/ClangFormatStyleOptions.rst b/clang/docs/ClangFormatStyleOptions.rst
index 8f23a4aa27a92..fa552d65e208a 100644
--- a/clang/docs/ClangFormatStyleOptions.rst
+++ b/clang/docs/ClangFormatStyleOptions.rst
@@ -3555,6 +3555,11 @@ the configuration (without a prefix: ``Auto``).
      false:
      import {VeryLongImportsAreAnnoying, VeryLongImportsAreAnnoying, VeryLongImportsAreAnnoying,} from "some/module.js"
 
+.. _KeepEmptyLinesAtEOF:
+
+**KeepEmptyLinesAtEOF** (``Boolean``) :versionbadge:`clang-format 17` :ref:`¶ <KeepEmptyLinesAtEOF>`
+  Keep empty lines (up to ``MaxEmptyLinesToKeep``) at end of file.
+
 .. _KeepEmptyLinesAtTheStartOfBlocks:
 
 **KeepEmptyLinesAtTheStartOfBlocks** (``Boolean``) :versionbadge:`clang-format 3.7` :ref:`¶ <KeepEmptyLinesAtTheStartOfBlocks>`

diff  --git a/clang/docs/ReleaseNotes.rst b/clang/docs/ReleaseNotes.rst
index a6b4a79b00a19..6bfd77cc91028 100644
--- a/clang/docs/ReleaseNotes.rst
+++ b/clang/docs/ReleaseNotes.rst
@@ -719,6 +719,7 @@ clang-format
 - Fix all known issues associated with ``LambdaBodyIndentation: OuterScope``.
 - Add ``BracedInitializerIndentWidth`` which can be used to configure
   the indentation level of the contents of braced init lists.
+- Add ``KeepEmptyLinesAtEOF`` to keep empty lines at end of file.
 
 libclang
 --------

diff  --git a/clang/include/clang/Format/Format.h b/clang/include/clang/Format/Format.h
index 6a9d435174cdd..74b3e15918184 100644
--- a/clang/include/clang/Format/Format.h
+++ b/clang/include/clang/Format/Format.h
@@ -2675,6 +2675,10 @@ struct FormatStyle {
   bool JavaScriptWrapImports;
   // clang-format on
 
+  /// Keep empty lines (up to ``MaxEmptyLinesToKeep``) at end of file.
+  /// \version 17
+  bool KeepEmptyLinesAtEOF;
+
   /// If true, the empty line at the start of blocks is kept.
   /// \code
   ///    true:                                  false:
@@ -4364,6 +4368,7 @@ struct FormatStyle {
            JavaImportGroups == R.JavaImportGroups &&
            JavaScriptQuotes == R.JavaScriptQuotes &&
            JavaScriptWrapImports == R.JavaScriptWrapImports &&
+           KeepEmptyLinesAtEOF == R.KeepEmptyLinesAtEOF &&
            KeepEmptyLinesAtTheStartOfBlocks ==
                R.KeepEmptyLinesAtTheStartOfBlocks &&
            Language == R.Language &&

diff  --git a/clang/lib/Format/Format.cpp b/clang/lib/Format/Format.cpp
index 6e2b6a662e7e1..5fee5e6c261a9 100644
--- a/clang/lib/Format/Format.cpp
+++ b/clang/lib/Format/Format.cpp
@@ -942,6 +942,7 @@ template <> struct MappingTraits<FormatStyle> {
     IO.mapOptional("JavaScriptWrapImports", Style.JavaScriptWrapImports);
     IO.mapOptional("KeepEmptyLinesAtTheStartOfBlocks",
                    Style.KeepEmptyLinesAtTheStartOfBlocks);
+    IO.mapOptional("KeepEmptyLinesAtEOF", Style.KeepEmptyLinesAtEOF);
     IO.mapOptional("LambdaBodyIndentation", Style.LambdaBodyIndentation);
     IO.mapOptional("LineEnding", Style.LineEnding);
     IO.mapOptional("MacroBlockBegin", Style.MacroBlockBegin);
@@ -1410,6 +1411,7 @@ FormatStyle getLLVMStyle(FormatStyle::LanguageKind Language) {
       /*Hex=*/0,     /*HexMinDigits=*/0};
   LLVMStyle.JavaScriptQuotes = FormatStyle::JSQS_Leave;
   LLVMStyle.JavaScriptWrapImports = true;
+  LLVMStyle.KeepEmptyLinesAtEOF = false;
   LLVMStyle.KeepEmptyLinesAtTheStartOfBlocks = true;
   LLVMStyle.LambdaBodyIndentation = FormatStyle::LBI_Signature;
   LLVMStyle.LineEnding = FormatStyle::LE_DeriveLF;

diff  --git a/clang/lib/Format/UnwrappedLineFormatter.cpp b/clang/lib/Format/UnwrappedLineFormatter.cpp
index 33be74dfe1b9f..5172deb494b2e 100644
--- a/clang/lib/Format/UnwrappedLineFormatter.cpp
+++ b/clang/lib/Format/UnwrappedLineFormatter.cpp
@@ -1425,7 +1425,9 @@ void UnwrappedLineFormatter::formatFirstToken(
     unsigned NewlineIndent) {
   FormatToken &RootToken = *Line.First;
   if (RootToken.is(tok::eof)) {
-    unsigned Newlines = std::min(RootToken.NewlinesBefore, 1u);
+    unsigned Newlines =
+        std::min(RootToken.NewlinesBefore,
+                 Style.KeepEmptyLinesAtEOF ? Style.MaxEmptyLinesToKeep + 1 : 1);
     unsigned TokenIndent = Newlines ? NewlineIndent : 0;
     Whitespaces->replaceWhitespace(RootToken, Newlines, TokenIndent,
                                    TokenIndent);

diff  --git a/clang/unittests/Format/ConfigParseTest.cpp b/clang/unittests/Format/ConfigParseTest.cpp
index 169c93d1143eb..6c720ec22054c 100644
--- a/clang/unittests/Format/ConfigParseTest.cpp
+++ b/clang/unittests/Format/ConfigParseTest.cpp
@@ -167,6 +167,7 @@ TEST(ConfigParseTest, ParsesConfigurationBools) {
   CHECK_PARSE_BOOL(IndentWrappedFunctionNames);
   CHECK_PARSE_BOOL(InsertBraces);
   CHECK_PARSE_BOOL(InsertNewlineAtEOF);
+  CHECK_PARSE_BOOL(KeepEmptyLinesAtEOF);
   CHECK_PARSE_BOOL(KeepEmptyLinesAtTheStartOfBlocks);
   CHECK_PARSE_BOOL(ObjCSpaceAfterProperty);
   CHECK_PARSE_BOOL(ObjCSpaceBeforeProtocolList);

diff  --git a/clang/unittests/Format/FormatTest.cpp b/clang/unittests/Format/FormatTest.cpp
index fa53cbd262def..ee64b3a041c38 100644
--- a/clang/unittests/Format/FormatTest.cpp
+++ b/clang/unittests/Format/FormatTest.cpp
@@ -25728,6 +25728,15 @@ TEST_F(FormatTest, InsertNewlineAtEOF) {
   verifyFormat("int i;\n", "int i;", Style);
 }
 
+TEST_F(FormatTest, KeepEmptyLinesAtEOF) {
+  FormatStyle Style = getLLVMStyle();
+  Style.KeepEmptyLinesAtEOF = true;
+
+  const StringRef Code{"int i;\n\n"};
+  verifyFormat(Code, Code, Style);
+  verifyFormat(Code, "int i;\n\n\n", Style);
+}
+
 TEST_F(FormatTest, SpaceAfterUDL) {
   verifyFormat("auto c = (4s).count();");
   verifyFormat("auto x = 5s .count() == 5;");