tutanota/buildSrc/graph.js

import fs from "fs"

function toDot(modules, output) {
	let buffer = "digraph G {\n"
	buffer += "edge [dir=back]\n"

	modules.forEach(m => {
		m.deps.forEach(dep => {
			buffer += `"${dep}" -> "${m.id}\n"`
		});
	});
	buffer += "}\n"
	fs.writeFileSync(output, buffer, {encoding: "utf8"})
}

function prune(modules) {
	let avail = modules.filter(m => m.deps.length == 0);
	if (!avail.length) {
		return;
	}

	let id = avail[0].id;
//    console.log("pruning", id);
	let index = modules.indexOf(avail[0]);
	modules.splice(index, 1);
	modules.forEach(m => {
		m.deps = m.deps.filter(dep => dep != id);
	});
	prune(modules);
}

function getPrefix(ids) {
	if (ids.length < 2) {
		return "";
	}
	return ids.reduce((prefix, val) => {
		while (val.indexOf(prefix) != 0) {
			prefix = prefix.substring(0, prefix.length - 1);
		}
		return prefix;
	});
}

/**
 * Plugin which will generate .dot file with dependency graph
 * @param options {{exclude: string, output: string, prune: boolean}}
 */
export default function plugin(options = {}) {
	let exclude = str => options.exclude && str.match(options.exclude);
	let output = options.output
	if (!output) throw new Error("Please specify output file")

	return {
		generateBundle(bundleOptions, bundle, isWrite) {
			let ids = [];
			for (const moduleId of this.moduleIds) {
				if (!exclude(moduleId)) {
					ids.push(moduleId);
				}
			}

			let prefix = getPrefix(ids);
			let strip = str => str.substring(prefix.length);

			let modules = [];
			ids.forEach(id => {
				let m = {
					id: strip(id),
					deps: this.getModuleInfo(id).importedIds.filter(x => !exclude(x)).map(strip)
				}
				if (exclude(m.id)) {
					return;
				}
				modules.push(m);
			});
			if (options.prune) {
				prune(modules);
			}
			toDot(modules, output);
		}
	}
}