Why is AllowShortBlocksOnASingleLine not working as expected?

I have a C source file I'm trying to format with clang-format. Ideally, I'd like to have it so that if it sees a one-line block like:

if(condition) { do_something(); }

then, it should leave it alone.

I saw the option AllowShortBlocksOnASingleLine and thought it would do the trick. Instead, what it's done is take the one line block (which I had originally):

if(new_node == NULL) { return; }

and moved the body to the next line like this:

if(new_node == NULL) { 
    return; 
}

along with some other similar blocks. This completely contradicts what I expect should happen.

My .clang-format file is below. What am I doing wrong here?

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;
        }
    }
}

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