[PATCH] D90246: [clang-format] Improve BAS_DontAlign+AllowAllArgumentsOnNextLine=false

[Alexander Richardson via Phabricator via cfe-commits]

arichardson created this revision.
arichardson added reviewers: MyDeveloperDay, JakeMerdichAMD, klimek.
Herald added subscribers: cfe-commits, krytarowski.
Herald added a project: clang.
arichardson requested review of this revision.

TokenAnnotator::splitPenalty() was always returning 0 for opening parens if
AlignAfterOpenBracket was set to BAS_DontAlign, the preferred point for
line breaking was always after the open paren and was ignoring
PenaltyBreakBeforeFirstCallParameter. This change restricts the zero
penalty to the AllowAllArgumentsOnNextLine case which results in improved
formatting for FreeBSD where we set AllowAllArgumentsOnNextLine: false
and a high value for PenaltyBreakBeforeFirstCallParameter to avoid breaking
after the open paren.

Before:
functionCall(

  paramA, paramB, paramC);

void functionDecl(

  int A, int B, int C)

After:
functionCall(paramA, paramB,

  paramC);

void functionDecl(int A, int B,

  int C)


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D90246

Files:
  clang/lib/Format/TokenAnnotator.cpp
  clang/unittests/Format/FormatTest.cpp


Index: clang/unittests/Format/FormatTest.cpp
===================================================================
--- clang/unittests/Format/FormatTest.cpp
+++ clang/unittests/Format/FormatTest.cpp
@@ -5003,6 +5003,60 @@
                Style);
 }
 
+TEST_F(FormatTest, AllowAllArgumentsOnNextLineDontAlign) {
+  // Check that AllowAllArgumentsOnNextLine is respected for both BAS_DontAlign
+  // and BAS_Align.
+  auto Style = getLLVMStyle();
+  Style.ColumnLimit = 35;
+  StringRef Input = "functionCall(paramA, paramB, paramC);\n"
+                    "void functionDecl(int A, int B, int C);";
+  Style.AllowAllArgumentsOnNextLine = false;
+  Style.AlignAfterOpenBracket = FormatStyle::BAS_DontAlign;
+  EXPECT_EQ(StringRef("functionCall(paramA, paramB,\n"
+                      "    paramC);\n"
+                      "void functionDecl(int A, int B,\n"
+                      "    int C);"),
+            format(Input, Style));
+  Style.AlignAfterOpenBracket = FormatStyle::BAS_Align;
+  EXPECT_EQ(StringRef("functionCall(paramA, paramB,\n"
+                      "             paramC);\n"
+                      "void functionDecl(int A, int B,\n"
+                      "                  int C);"),
+            format(Input, Style));
+  // However, BAS_AlwaysBreak should take precedence over
+  // AllowAllArgumentsOnNextLine.
+  Style.AlignAfterOpenBracket = FormatStyle::BAS_AlwaysBreak;
+  EXPECT_EQ(StringRef("functionCall(\n"
+                      "    paramA, paramB, paramC);\n"
+                      "void functionDecl(\n"
+                      "    int A, int B, int C);"),
+            format(Input, Style));
+
+  // When AllowAllArgumentsOnNextLine is set, we prefer breaking before the
+  // first argument.
+  Style.AllowAllArgumentsOnNextLine = true;
+  Style.AlignAfterOpenBracket = FormatStyle::BAS_AlwaysBreak;
+  EXPECT_EQ(StringRef("functionCall(\n"
+                      "    paramA, paramB, paramC);\n"
+                      "void functionDecl(\n"
+                      "    int A, int B, int C);"),
+            format(Input, Style));
+  // It wouldn't fit on one line with aligned parameters so this setting
+  // doesn't change anything for BAS_Align.
+  Style.AlignAfterOpenBracket = FormatStyle::BAS_Align;
+  EXPECT_EQ(StringRef("functionCall(paramA, paramB,\n"
+                      "             paramC);\n"
+                      "void functionDecl(int A, int B,\n"
+                      "                  int C);"),
+            format(Input, Style));
+  Style.AlignAfterOpenBracket = FormatStyle::BAS_DontAlign;
+  EXPECT_EQ(StringRef("functionCall(\n"
+                      "    paramA, paramB, paramC);\n"
+                      "void functionDecl(\n"
+                      "    int A, int B, int C);"),
+            format(Input, Style));
+}
+
 TEST_F(FormatTest, BreakConstructorInitializersAfterColon) {
   FormatStyle Style = getLLVMStyle();
   Style.BreakConstructorInitializers = FormatStyle::BCIS_AfterColon;
Index: clang/lib/Format/TokenAnnotator.cpp
===================================================================
--- clang/lib/Format/TokenAnnotator.cpp
+++ clang/lib/Format/TokenAnnotator.cpp
@@ -2745,7 +2745,11 @@
   if (Left.is(TT_TemplateOpener))
     return 100;
   if (Left.opensScope()) {
-    if (Style.AlignAfterOpenBracket == FormatStyle::BAS_DontAlign)
+    // If we aren't aligning after opening parens/braces we can always break
+    // here unless the style does not want us to place all arguments on the
+    // next line.
+    if (Style.AlignAfterOpenBracket == FormatStyle::BAS_DontAlign &&
+        (Left.ParameterCount <= 1 || Style.AllowAllArgumentsOnNextLine))
       return 0;
     if (Left.is(tok::l_brace) && !Style.Cpp11BracedListStyle)
       return 19;


-------------- next part --------------
A non-text attachment was scrubbed...
Name: D90246.301035.patch
Type: text/x-patch
Size: 3750 bytes
Desc: not available
URL: <http://lists.llvm.org/pipermail/cfe-commits/attachments/20201027/fd964ef7/attachment.bin>