Test for https://github.com/gulp-sourcemaps/gulp-sourcemaps/issues/368

test368.bash

echo 'body {color: pink}' > pink.less
echo "{}" > package.json
cat << HEREDOC > gulpfile.js
const gulp = require("gulp");
const plug = require("gulp-load-plugins")();

gulp.task("default", () => gulp
	.src("pink.less")
	.pipe(plug.sourcemaps.init())
	.pipe(plug.less())
	.pipe(plug.sourcemaps.write("./", {includeContent: false, sourceRoot: "a/"}))
	.pipe(gulp.dest("b/"))
	.pipe(plug.ignore.exclude("*.map"))
	.pipe(plug.cssnano())
	.pipe(plug.sourcemaps.write("./", {includeContent: false, sourceRoot: "c/"}))
	.pipe(gulp.dest("d/"))
);
HEREDOC

npm install --save gulp@3 gulp-load-plugins gulp-sourcemaps gulp-less gulp-ignore gulp-cssnano
gulp