feat: initial angular support + clean up tests

packages/webpack5/jest.setup.ts

@@ -1,5 +1,15 @@
+// define our global helpers
+declare global {
+	function mockFile(path: string, content: string);
+}
+
+// enable TEST mode
+global.__TEST__ = true;
+
 // we are mocking the cwd for the tests, since webpack needs absolute paths
 // and we don't want them in tests
+import dedent from 'ts-dedent';
+
 process.cwd = () => '__jest__';
 
 // a virtual mock for package.json
@@ -22,10 +32,51 @@ jest.mock('cosmiconfig', () => ({
 	},
 }));
 
-jest.mock('path', () => ({
-	...jest.requireActual('path'),
-	// we are mocking resolve to just simply join the paths for tests
-	resolve(...args) {
-		return args.join('/');
-	},
-}));
+jest.mock('path', () => {
+	const path = jest.requireActual('path');
+	return {
+		...path,
+		resolve(...args) {
+			if (args[0] === '__jest__') {
+				return path.join(...args);
+			}
+
+			const resolved = path.resolve(...args);
+			if (resolved.includes('__jest__')) {
+				const li = resolved.lastIndexOf('__jest__');
+				return resolved.substr(li);
+			}
+
+			return resolved;
+		},
+	};
+});
+
+const mockedFiles: { [path: string]: string } = {};
+
+global.mockFile = function mockFile(path, content) {
+	const unionFS = require('unionfs').default;
+	const Volume = require('memfs').Volume;
+
+	// reset to fs
+	unionFS.reset();
+
+	// add mocked file
+	mockedFiles[path] = dedent(content);
+
+	// create new volume
+	const vol = Volume.fromJSON(mockedFiles, '__jest__');
+
+	// use the new volume
+	unionFS.use(vol as any);
+};
+
+jest.mock('fs', () => {
+	const fs = jest.requireActual('fs');
+	const unionFS = require('unionfs').default;
+	unionFS.reset = () => {
+		unionFS.fss = [fs];
+	};
+
+	return unionFS.use(fs);
+});