AllowShortBlocksOnASingleLine未按预期工作，求排查配置问题

我在用clang-format格式化C源文件，希望单行代码块比如：

if(condition) { do_something(); }

能保持原样。我开启了AllowShortBlocksOnASingleLine选项，本以为能满足需求，但实际它把原本的单行块比如：

if(new_node == NULL) { return; }

拆成了多行：

if(new_node == NULL) { 
    return; 
}

其他类似代码块也出现同样情况，完全不符合预期。以下是我的代码示例和.clang-format配置文件，请问哪里配置错了？

代码示例 #

static Node *
create_node(MAT_VERTEX v)
{
    Node *new_node = malloc(sizeof(Node));
    if(new_node == NULL) {
        return;
    }

    while(1) {
        return;
    }

    new_node->data = v;
    new_node->next = NULL;
    return new_node;

    enum FOOD breakfast = cereal;

    switch(breakfast) {
        case eggs: {
            int x = 3;
            int y;
            for(y = 5; y < x; y--) { }

            break;
        }
        case bacon: {
            int x = 4;
            if(x != 0) {
                int y = -5;
            }

            break;
        }
        case ham: {
            int decision = 1;
            int traffic = 1;
            if(decision) {
                traffic = 0;
                do_nothing_function();
            }
            else {
                traffic = 3;
                another_do_nothing_function();
            }

            break;
        }
        default: {
            break;
        }
    }
}

.clang-format配置文件 #

Language:             Cpp

BreakBeforeBraces:    Custom
BraceWrapping:
  AfterCaseLabel:     false
  AfterClass:         false
  AfterControlStatement:  Never
  AfterFunction:      true
  AfterNamespace:     false
  AfterStruct:        false
  AfterUnion:         false
  AfterExternBlock:   false
  BeforeCatch:        true
  BeforeElse:         true
  BeforeWhile:        false
  IndentBraces:       false
  SplitEmptyFunction: true

AllowShortBlocksOnASingleLine: Always
# AllowShortIfStatementsOnASingleLine: Never
AllowShortFunctionsOnASingleLine: None

IndentCaseBlocks:     false
IndentCaseLabels:     true

IndentWidth:          4

PointerAlignment:     Right
QualifierAlignment:   Leave

SeparateDefinitionBlocks: Leave

AlignAfterOpenBracket:  Align
BinPackParameters:    false
BinPackArguments:     false
AlwaysBreakAfterReturnType: TopLevelDefinitions

MaxEmptyLinesToKeep:  5

IncludeBlocks:        Preserve
SortIncludes:         Never

SpaceAfterCStyleCast:               false
SpaceAfterLogicalNot:               false
SpaceAfterTemplateKeyword:          false
SpaceAroundPointerQualifiers:       Default
SpaceBeforeAssignmentOperators:     true
SpaceBeforeCaseColon:               false
SpaceBeforeParens:                  Never
SpaceBeforeRangeBasedForLoopColon:  true
SpaceBeforeSquareBrackets:          false
SpaceInEmptyBlock:                  true
SpaceInEmptyParentheses:            false
SpacesBeforeTrailingComments:       3
SpacesInContainerLiterals:          false
SpacesInSquareBrackets:             false

问题出在BraceWrapping下的AfterControlStatement配置。你设置的Never会强制控制语句（if/while等）后的大括号必须换行，这直接覆盖了AllowShortBlocksOnASingleLine的生效逻辑。

需要把AfterControlStatement从Never改成MultiLine，这样clang-format会对单行短代码块保持原样，仅对包含多行内容的代码块换行处理。

修改后的BraceWrapping部分配置如下：

BraceWrapping:
  AfterCaseLabel:     false
  AfterClass:         false
  AfterControlStatement:  MultiLine  # 修改此处
  AfterFunction:      true
  AfterNamespace:     false
  AfterStruct:        false
  AfterUnion:         false
  AfterExternBlock:   false
  BeforeCatch:        true
  BeforeElse:         true
  BeforeWhile:        false
  IndentBraces:       false
  SplitEmptyFunction: true

如果还希望if语句的条件判断和整个代码块完全在一行（比如if(cond){do();}），可以取消注释AllowShortIfStatementsOnASingleLine并设置为Always，这一步可根据你的实际格式需求选择。

内容的提问来源于stack exchange，提问作者Mode77