[clang-format] [PR25010] AllowShortIfStatementsOnASingleLine not working if an "else" statement is present

Summary:
Addressing: PR25010 - https://bugs.llvm.org/show_bug.cgi?id=25010

Code like:

```
    if(true) var++;
    else  {
        var--;
    }
```

is reformatted to be

```
  if (true)
    var++;
  else {
    var--;
  }
```

Even when `AllowShortIfStatementsOnASingleLine` is true

The following revision comes from a +1'd suggestion in the PR to support AllowShortIfElseStatementsOnASingleLine

This suppresses the clause prevents the merging of the if when there is a compound else

Reviewers: klimek, djasper, JonasToth, alexfh, krasimir, reuk
Reviewed By: reuk
Subscribers: reuk, Higuoxing, jdoerfert, cfe-commits
Tags: #clang-tools-extra
Differential Revision: https://reviews.llvm.org/D59087

llvm-svn: 356029

1 files changed, 20 insertions, 6 deletions

diff --git a/clang/lib/Format/Format.cpp b/clang/lib/Format/Format.cpp
index a56fed9dee1..ce67b82e10b 100644
--- a/clang/lib/Format/Format.cpp
+++ b/clang/lib/Format/Format.cpp
@@ -106,6 +106,18 @@ template <> struct ScalarEnumerationTraits<FormatStyle::ShortFunctionStyle> {
   }
 };
 
+template <> struct ScalarEnumerationTraits<FormatStyle::ShortIfStyle> {
+  static void enumeration(IO &IO, FormatStyle::ShortIfStyle &Value) {
+    IO.enumCase(Value, "Never", FormatStyle::SIS_Never);
+    IO.enumCase(Value, "Always", FormatStyle::SIS_Always);
+    IO.enumCase(Value, "WithoutElse", FormatStyle::SIS_WithoutElse);
+
+    // For backward compatibility.
+    IO.enumCase(Value, "false", FormatStyle::SIS_Never);
+    IO.enumCase(Value, "true", FormatStyle::SIS_WithoutElse);
+  }
+};
+
 template <> struct ScalarEnumerationTraits<FormatStyle::BinPackStyle> {
   static void enumeration(IO &IO, FormatStyle::BinPackStyle &Value) {
     IO.enumCase(Value, "Auto", FormatStyle::BPS_Auto);
@@ -631,7 +643,7 @@ FormatStyle getLLVMStyle(FormatStyle::LanguageKind Language) {
   LLVMStyle.AllowShortFunctionsOnASingleLine = FormatStyle::SFS_All;
   LLVMStyle.AllowShortBlocksOnASingleLine = false;
   LLVMStyle.AllowShortCaseLabelsOnASingleLine = false;
-  LLVMStyle.AllowShortIfStatementsOnASingleLine = false;
+  LLVMStyle.AllowShortIfStatementsOnASingleLine = FormatStyle::SIS_Never;
   LLVMStyle.AllowShortLoopsOnASingleLine = false;
   LLVMStyle.AlwaysBreakAfterReturnType = FormatStyle::RTBS_None;
   LLVMStyle.AlwaysBreakAfterDefinitionReturnType = FormatStyle::DRTBS_None;
@@ -737,7 +749,8 @@ FormatStyle getGoogleStyle(FormatStyle::LanguageKind Language) {
 
   GoogleStyle.AccessModifierOffset = -1;
   GoogleStyle.AlignEscapedNewlines = FormatStyle::ENAS_Left;
-  GoogleStyle.AllowShortIfStatementsOnASingleLine = true;
+  GoogleStyle.AllowShortIfStatementsOnASingleLine =
+      FormatStyle::SIS_WithoutElse;
   GoogleStyle.AllowShortLoopsOnASingleLine = true;
   GoogleStyle.AlwaysBreakBeforeMultilineStrings = true;
   GoogleStyle.AlwaysBreakTemplateDeclarations = FormatStyle::BTDS_Yes;
@@ -804,7 +817,7 @@ FormatStyle getGoogleStyle(FormatStyle::LanguageKind Language) {
     GoogleStyle.AlignOperands = false;
     GoogleStyle.AlignTrailingComments = false;
     GoogleStyle.AllowShortFunctionsOnASingleLine = FormatStyle::SFS_Empty;
-    GoogleStyle.AllowShortIfStatementsOnASingleLine = false;
+    GoogleStyle.AllowShortIfStatementsOnASingleLine = FormatStyle::SIS_Never;
     GoogleStyle.AlwaysBreakBeforeMultilineStrings = false;
     GoogleStyle.BreakBeforeBinaryOperators = FormatStyle::BOS_NonAssignment;
     GoogleStyle.ColumnLimit = 100;
@@ -846,7 +859,8 @@ FormatStyle getGoogleStyle(FormatStyle::LanguageKind Language) {
 FormatStyle getChromiumStyle(FormatStyle::LanguageKind Language) {
   FormatStyle ChromiumStyle = getGoogleStyle(Language);
   if (Language == FormatStyle::LK_Java) {
-    ChromiumStyle.AllowShortIfStatementsOnASingleLine = true;
+    ChromiumStyle.AllowShortIfStatementsOnASingleLine =
+        FormatStyle::SIS_WithoutElse;
     ChromiumStyle.BreakAfterJavaFieldAnnotations = true;
     ChromiumStyle.ContinuationIndentWidth = 8;
     ChromiumStyle.IndentWidth = 4;
@@ -859,12 +873,12 @@ FormatStyle getChromiumStyle(FormatStyle::LanguageKind Language) {
     };
     ChromiumStyle.SortIncludes = true;
   } else if (Language == FormatStyle::LK_JavaScript) {
-    ChromiumStyle.AllowShortIfStatementsOnASingleLine = false;
+    ChromiumStyle.AllowShortIfStatementsOnASingleLine = FormatStyle::SIS_Never;
     ChromiumStyle.AllowShortLoopsOnASingleLine = false;
   } else {
     ChromiumStyle.AllowAllParametersOfDeclarationOnNextLine = false;
     ChromiumStyle.AllowShortFunctionsOnASingleLine = FormatStyle::SFS_Inline;
-    ChromiumStyle.AllowShortIfStatementsOnASingleLine = false;
+    ChromiumStyle.AllowShortIfStatementsOnASingleLine = FormatStyle::SIS_Never;
     ChromiumStyle.AllowShortLoopsOnASingleLine = false;
     ChromiumStyle.BinPackParameters = false;
     ChromiumStyle.DerivePointerAlignment = false;