Move Factorio server implementation to host

Move Factorio related code in lib that's only used by the host into the
host package.

test/host/patch.js

@@ -0,0 +1,184 @@
+"use strict";
+const assert = require("assert").strict;
+const fs = require("fs-extra");
+const JSZip = require("jszip");
+const path = require("path");
+
+const patch = require("@clusterio/host/src/patch");
+
+
+describe("host/patch", function() {
+	describe("generateLoader()", function() {
+		let reference = [
+			"-- Auto generated scenario module loader created by Clusterio",
+			"-- Modifications to this file will be lost when loaded in Clusterio",
+			"clusterio_patch_number = 1",
+			"",
+			'local event_handler = require("event_handler")',
+			"",
+			"-- Scenario modules",
+			'event_handler.add_lib(require("foo"))',
+			"",
+			"-- Clusterio modules",
+			'event_handler.add_lib(require("modules/spam/bar"))',
+			'require("modules/spam/spam")',
+			"",
+		].join("\n");
+		let patchInfo = {
+			"patch_number": 1,
+			"scenario": { "modules": ["foo"] },
+			"modules": [{
+				"name": "spam",
+				"files": [
+					{ "path": "bar.lua", "load": true, "require": false },
+					{ "path": "spam.lua", "load": false, "require": true },
+					{ "path": "excluded.lua", "load": false, "require": false },
+				],
+			}],
+		};
+
+		it("should produce output matching the reference", function() {
+			assert.equal(patch._generateLoader(patchInfo), reference);
+		});
+	});
+
+	describe("reorderDependencies()", function() {
+		it("should reorder to satisfy simple dependency", function() {
+			let modules = [
+				{ name: "a", version: "1.0.0", dependencies: {"b": "*"} },
+				{ name: "b", version: "1.0.0", dependencies: {} },
+			];
+			patch._reorderDependencies(modules);
+			assert(modules[0].name === "b", "Dependency was not reorederd");
+		});
+		it("should throw on invalid version", function() {
+			let modules = [
+				{ name: "a", version: "foo", dependencies: {} },
+			];
+			assert.throws(
+				() => patch._reorderDependencies(modules),
+				new Error("Invalid version 'foo' for module a")
+			);
+		});
+		it("should throw on invalid version range", function() {
+			let modules = [
+				{ name: "a", version: "1.0.0", dependencies: {"b": "invalid"} },
+			];
+			assert.throws(
+				() => patch._reorderDependencies(modules),
+				new Error("Invalid version range 'invalid' for dependency b on module a")
+			);
+		});
+		it("should throw on missing dependency", function() {
+			let modules = [
+				{ name: "a", version: "1.0.0", dependencies: {"b": "*"} },
+			];
+			assert.throws(
+				() => patch._reorderDependencies(modules),
+				new Error("Missing dependency b for module a")
+			);
+			modules = [
+				{ name: "a", version: "1.0.0", dependencies: {"b": "*"} },
+				{ name: "b", version: "1.0.0", dependencies: {"c": "*"} },
+				{ name: "c", version: "1.0.0", dependencies: {"d": "*"} },
+			];
+			assert.throws(
+				() => patch._reorderDependencies(modules),
+				new Error("Missing dependency d for module c")
+			);
+		});
+		it("should throw on outdated dependency", function() {
+			let modules = [
+				{ name: "a", version: "1.0.0", dependencies: {} },
+				{ name: "b", version: "1.0.0", dependencies: {"a": ">=2"} },
+			];
+			assert.throws(
+				() => patch._reorderDependencies(modules),
+				new Error("Module b requires a >=2")
+			);
+		});
+		it("should throw on dependency loops", function() {
+			let modules = [
+				{ name: "a", version: "1.0.0", dependencies: {"b": "*"} },
+				{ name: "b", version: "1.0.0", dependencies: {"a": "*"} },
+			];
+			assert.throws(
+				() => patch._reorderDependencies(modules),
+				new Error("Module dependency loop detected: a -> b -> a")
+			);
+			modules = [
+				{ name: "d", version: "1.0.0", dependencies: {"b": "*"} },
+				{ name: "a", version: "1.0.0", dependencies: {"b": "*"} },
+				{ name: "b", version: "1.0.0", dependencies: {"c": "*"} },
+				{ name: "c", version: "1.0.0", dependencies: {"a": "*"} },
+			];
+			assert.throws(
+				() => patch._reorderDependencies(modules),
+				new Error("Module dependency loop detected: b -> c -> a -> b")
+			);
+		});
+		it("should reorder correctly for multiple dependencies", function() {
+			function validate(modules) {
+				let present = new Set();
+				for (let module of modules) {
+					for (let dependency of Object.keys(module.dependencies)) {
+						if (!present.has(dependency)) {
+							assert.fail(`${module.name} depends on ${dependency}, but was ordered before it`);
+						}
+					}
+					present.add(module.name);
+				}
+			}
+
+			let names = ["a", "b", "c"];
+			let successCount = 0;
+			const bitCount = names.length * (names.length - 1);
+			for (let i=0; i < 2**bitCount; i++) {
+				let value = i;
+				let bits = [];
+				for (let j=0; j < bitCount; j++) {
+					bits.push(value & 1);
+					value >>= 1;
+				}
+				let modules = [];
+				for (let j=0; j < names.length; j++) {
+					let name = names[j];
+					let dependencies = {};
+					for (let k=0; k < names.length - 1; k++) {
+						if (bits[k + j * (names.length - 1)]) {
+							dependencies[names[k + (k >= j)]] = "*";
+						}
+					}
+					modules.push({ name, version: "1.0.0", dependencies });
+				}
+				let success = false;
+				try {
+					patch._reorderDependencies(modules);
+					success = true;
+				} catch (err) { }
+				if (success) {
+					validate(modules);
+					successCount += 1;
+				}
+			}
+
+			// Deriving the formula for the number of graphs without
+			// dependencies loops is left as an excercise for the reader.
+			assert(successCount === 25, "Incorrect number of successful orderings");
+		});
+	});
+
+	describe("patch()", function() {
+		it("should throw on unknown scenario", async function() {
+			let zip = new JSZip();
+			zip.file("world/control.lua", "-- unknown\n");
+			let zipPath = path.join("temp", "test", "patch.zip");
+			await fs.outputFile(zipPath, await zip.generateAsync({ type: "nodebuffer" }));
+
+			await assert.rejects(
+				patch.patch(zipPath, []),
+				new Error("Unable to patch save, unknown scenario (3acc3be3861144e55604f5ac2f2555071885ebc4)")
+			);
+		});
+	});
+});