Is sasl-dart required for Quarto operation?

[yurivict]

Description

Is sass-dart only required for binary executable generation?

Can libsass https://sass-lang.com/libsass (https://github.com/sass/libsass) substitute sasl-dart for the purposes of Quarto?

Motivation: I am trying to create the FreeBSD port for Quarto, but the sasl-dart dependency depends in turn on Dart which seems to be hard to port. I am trying to understand how necessary sasl-dart is for Quarto.

[cscheid]

I think you do need the binary to make Quarto work as is (because I imagine that the CLI arguments aren't equivalent).

You could attempt a fork and fix, but we would prefer for that to be first merged to Quarto instead of going directly to FreeBSD. Otherwise, we wouldn't be able to offer any support, and SCSS compilation is a large part of our HTML formats; it would be very important to get that perfectly right.

For what's worth, this is a part of quarto-cli that is pretty well-architected and well-factored. All invocations go through dartCommand (which admittedly isn't the best name for what it does), defined here:

quarto-cli/src/core/dart-sass.ts

Lines 55 to 103 in 92cad44

	export async function dartCommand(args: string[]) {
	const resolvePath = () => {
	const dartOverrideCmd = Deno.env.get("QUARTO_DART_SASS");
	if (dartOverrideCmd) {
	if (!existsSync(dartOverrideCmd)) {
	warnOnce(
	`Specified QUARTO_DART_SASS does not exist, using built in dart sass.`,
	);
	} else {
	return dartOverrideCmd;
	}
	}
	const command = Deno.build.os === "windows" ? "sass.bat" : "sass";
	return architectureToolsPath(join("dart-sass", command));
	};
	const sass = resolvePath();
	const cmd = [
	sass,
	...args,
	];
	// Run the sass compiler
	const result = await execProcess(
	{
	cmd,
	stdout: "piped",
	stderr: "piped",
	},
	);
	if (result.success) {
	if (result.stderr) {
	info(result.stderr);
	}
	return result.stdout;
	} else {
	debug(`[DART path] : ${sass}`);
	debug(`[DART args] : ${args.join(" ")}`);
	debug(`[DART stdout] : ${result.stdout}`);
	debug(`[DART stderr] : ${result.stderr}`);
	const errLines = lines(result.stderr || "");
	// truncate the last 2 lines (they include a pointer to the temp file containing
	// all of the concatenated sass, which is more or less incomprehensible for users.
	const errMsg = errLines.slice(0, errLines.length - 2).join("\n");
	throw new Error("Theme file compilation failed:\n\n" + errMsg);
	}
	}

It should be possible for you to try this out and report back.