clang-format weird indentation of array of structs in C++

Question

I'm trying to use clang-format (in VS code) to format my C++ files and configure it to my preferred style. For an array of structs (for getopts) it is adding a load of extra spaces and messing up the brace wrapping:

I'll append my .clang-format at the end of this query

Here's the way I want my array to appear:

int main()
{
 const struct option longopts[]=
 {
 {"log-file", required_argument, 0, LOGFILE},
 {"log-level", required_argument, 0, LOGLEVEL},
 {nullptr, 0, nullptr, 0}
 };
}

Here's how it actually appears:

int main()
{
 const struct option longopts[] =
 {
 {"log-file", required_argument, 0, LOGFILE},
 {"log-level", required_argument, 0, LOGLEVEL},
 {nullptr, 0, nullptr, 0}};
}

My .clang-format file contains:

BasedOnStyle: LLVM
IndentWidth: 2
AlignAfterOpenBracket: Align
AlignTrailingComments: true
AllowAllParametersOfDeclarationOnNextLine: true
AllowShortFunctionsOnASingleLine: true
AllowShortBlocksOnASingleLine: true
BinPackParameters: true
BreakBeforeBraces: Custom
BraceWrapping:
 AfterClass: true
 AfterControlStatement: true
 AfterEnum: true
 AfterFunction: true
 AfterNamespace: true
 AfterObjCDeclaration: true
 AfterStruct: true
 AfterUnion: true
 AfterExternBlock: true
 BeforeCatch: true
 BeforeElse: true
 IndentBraces: false
 SplitEmptyFunction: false
 SplitEmptyRecord: false
 SplitEmptyNamespace: false
BreakConstructorInitializers: AfterColon
ColumnLimit: 0
ConstructorInitializerAllOnOneLineOrOnePerLine: false
IndentCaseLabels: true
KeepEmptyLinesAtTheStartOfBlocks: true
NamespaceIndentation: All
PointerAlignment: Right
SortIncludes: false
SpaceBeforeAssignmentOperators: true
SpaceBeforeParens: Never
SpaceInEmptyParentheses: false
SpacesInContainerLiterals: false
SpacesInAngles: false
SpacesInParentheses: false
SpacesInSquareBrackets: false
UseTab: Never

Any solutions welcome!

Answer 1

I'm not sure that exactly what you want could be achived, but sometimes easiest way is to slighly modify the source file to help-up the clang-format utility. At first you need to add an ContinuationIndentWidth: 2 option to your format file. Then add a comma after the last item in the array:

{nullptr, 0, nullptr, 0}, // <---

And finnaly move the first curly brace on the same line as array name. The resulting file will be like this:

int main()
{
 const struct option longopts[] = {
 {"log-file", required_argument, 0, LOGFILE},
 {"log-level", required_argument, 0, LOGLEVEL},
 {nullptr, 0, nullptr, 0},
 };
}

Running the clang-format will leave it as it is. Tested on clang-format from the LLVM snapshot build LLVM-9.0.0-r351376-win64.exe.

• Phil Evans: Thanks! As you say, not quite perfect because of where the opening brace ends up, but a lot better than it was!