When the formatting is not correct, we print a clang-format command line for how to fix it.
That relies on the version of clang-format installed globally by npm, which may differ from the version used in the project's node_modules.
As a result, the formatting produced by running the command may not fix the warnings from the gulp build. We should print a command line which uses the same version as gulp task will use.

const clangFormat = require('gulp-clang-format');
const gulp = require('gulp');

gulp.task('format', () =>
{
	let src = 'src/**/*.cpp';

	return gulp.src(src, { base: '.' })
		.pipe(clangFormat.format('file'))
		.pipe(gulp.dest('.'));
});

Runnin the gulp format task achieves its purpose and modifies source files according to rules in .clang-format. But, the modification time of those modified files do not change.

This is annoying when you have such a file into a text editor, run gulp format in a terminal, the file is modified, but the text editor has no way to realize of it so the display is not refreshed.

As a suggestion, format() may invoke touch in modified files.

P.S.: This may be an issue of clang-format itself.

broccoli-typescript.ts keeps on failing the gulp check-format task in angular/angular even after the file has been formatted with clang-format and rerunning clang-format yields zero delta.

is it possible that the way the two streams are compared is not always reliable?

When upgrading transitive dependencies of gulp-clang-format in angular/angular I started seeing frequent but random false positives when running gulp check-format.

I was able to narrow the issue down to gulp-clang-format's stream-equal dependency. Version 0.1.6 works just fine but 0.1.7 exhibits this problem.

I haven't investigated if this is happening due to a bug in stream-equal or due to how we use it.

For now I'm going to limit the stream-equal transitive dependency of gulp-clang-format to <=0.1.6.

Instead of providing a formatted directory, is it possible to overwrite the files instead?

Thanks