clang-format always aligns stream operator << with spaces

[knarfS]

Description

The UseTab option is set to Always, but clang-format is using spaces to align the << operator in continued lines. This behavior occurs even when all the Align* options are set to false. Also BreakBeforeBinaryOperators has no influence on the alignment (or even breaking before/after) of the stream operator <<.

The unwanted leading spaces then trigger other format checkers like EditorConfig (which is set to indent_style·=·tab)

Steps to reproduce

1. Create a minimal .clang-format file with the following configuration:

---
AlignAfterOpenBracket: DontAlign
AlignConsecutiveMacros: false
AlignConsecutiveAssignments: false
AlignConsecutiveDeclarations: false
AlignEscapedNewlines: Left
AlignOperands: DontAlign
AlignTrailingComments: false
BreakBeforeBinaryOperators: NonAssignment
ColumnLimit: 80
ContinuationIndentWidth: 4
IndentWidth: 4
TabWidth: 4
UseTab: Always
...

2. Use clang-format to format the following code:

void someFunction() {
	std::cout << someVariable << "Some random string for std::cout " << someOtherVariable << ", "
		<< andAnotherOne << andOneMore << ", some final text.";
}

Expected behavior

The << operators in the continued lines should not be aligned and only be indented with tab characters, not with spaces:

void someFunction() {
	std::cout << someVariable << "Some random string for std::cout "
		<< someOtherVariable << ", " << andAnotherOne << andOneMore
		<< ", some final text.";
}

Actual behavior

The << operators in the continued lines are indented with three tabs and with two additional spaces for alignment:

void someFunction() {
	std::cout << someVariable << "Some random string for std::cout "
			  << someOtherVariable << ", " << andAnotherOne << andOneMore
			  << ", some final text.";
}

Environment

• clang-format version: Debian clang-format version 14.0.6
• Operating system: Debian Testing x86_64

[knarfS]

The issue #44363 is somewhat related to this issue. It describes a not configurable and in some cases unwanted behavior when it comes to stream operators and breaking lines.

[llvmbot]

@llvm/issue-subscribers-clang-format