polyfill for zip

Author: skoob13

apps/twig/package.json

@@ -141,6 +141,7 @@
     "dotenv": "^17.2.3",
     "electron-log": "^5.4.3",
     "electron-store": "^11.0.0",
+    "fflate": "^0.8.2",
     "file-icon": "^6.0.0",
     "framer-motion": "^12.26.2",
     "fzf": "^0.5.2",
@@ -166,11 +167,11 @@
     "remark-breaks": "^4.0.0",
     "remark-gfm": "^4.0.1",
     "sonner": "^2.0.7",
+    "striptags": "^3.2.0",
     "tippy.js": "^6.3.7",
     "uuid": "^9.0.1",
     "vscode-icons-js": "^11.6.1",
     "zod": "^4.1.12",
-    "zustand": "^4.5.0",
-    "striptags": "^3.2.0"
+    "zustand": "^4.5.0"
   }
 }

apps/twig/src/main/lib/extract-zip.ts

@@ -0,0 +1,23 @@
+import { mkdir, readFile, writeFile } from "node:fs/promises";
+import { dirname, join } from "node:path";
+import { unzipSync } from "fflate";
+
+/**
+ * Extracts a ZIP file to a directory using fflate (cross-platform, no native dependencies).
+ */
+export async function extractZip(
+  zipPath: string,
+  extractDir: string,
+): Promise<void> {
+  const data = await readFile(zipPath);
+  const unzipped = unzipSync(new Uint8Array(data));
+  for (const [filename, content] of Object.entries(unzipped)) {
+    const fullPath = join(extractDir, filename);
+    if (filename.endsWith("/")) {
+      await mkdir(fullPath, { recursive: true });
+    } else {
+      await mkdir(dirname(fullPath), { recursive: true });
+      await writeFile(fullPath, content);
+    }
+  }
+}

apps/twig/src/main/services/posthog-plugin/service.test.ts

@@ -16,8 +16,8 @@ const mockNet = vi.hoisted(() => ({
   fetch: vi.fn(),
 }));
 
-const mockExecFileAsync = vi.hoisted(() =>
-  vi.fn<(cmd: string, args: string[]) => Promise<unknown>>(async () => {}),
+const mockExtractZip = vi.hoisted(() =>
+  vi.fn<(zipPath: string, extractDir: string) => Promise<void>>(async () => {}),
 );
 
 vi.mock("electron", () => ({
@@ -35,14 +35,8 @@ vi.mock("node:fs/promises", async () => {
   return { ...fs.promises, default: fs.promises };
 });
 
-vi.mock("node:child_process", () => ({
-  execFile: vi.fn(),
-  default: { execFile: vi.fn() },
-}));
-
-vi.mock("node:util", () => ({
-  promisify: () => mockExecFileAsync,
-  default: { promisify: () => mockExecFileAsync },
+vi.mock("../../lib/extract-zip.js", () => ({
+  extractZip: mockExtractZip,
 }));
 
 vi.mock("node:os", () => ({
@@ -82,21 +76,19 @@ function mockFetchResponse(ok: boolean, status = 200) {
   };
 }
 
-/** Simulate unzip by creating skill files in the extracted dir */
-function simulateUnzip() {
-  mockExecFileAsync.mockImplementation(async (_cmd: string, args: string[]) => {
-    const dIdx = args.indexOf("-d");
-    if (dIdx >= 0) {
-      const extractDir = args[dIdx + 1];
+/** Simulate zip extraction by creating skill files in the extracted dir */
+function simulateExtractZip() {
+  mockExtractZip.mockImplementation(
+    async (_zipPath: string, extractDir: string) => {
       vol.mkdirSync(`${extractDir}/skills/remote-skill`, {
         recursive: true,
       });
       vol.writeFileSync(
         `${extractDir}/skills/remote-skill/SKILL.md`,
         "# Remote",
       );
-    }
-  });
+    },
+  );
 }
 
 /** Create the bundled plugin directory in memfs */
@@ -116,7 +108,7 @@ describe("PosthogPluginService", () => {
 
     mockApp.isPackaged = false;
     mockNet.fetch.mockResolvedValue(mockFetchResponse(true));
-    mockExecFileAsync.mockResolvedValue({});
+    mockExtractZip.mockResolvedValue(undefined);
 
     service = new PosthogPluginService();
   });
@@ -204,7 +196,7 @@ describe("PosthogPluginService", () => {
   describe("updateSkills", () => {
     it("downloads, extracts, and installs skills", async () => {
       setupBundledPlugin();
-      simulateUnzip();
+      simulateExtractZip();
 
       await service.updateSkills();
 
@@ -215,10 +207,7 @@ describe("PosthogPluginService", () => {
       expect(mockNet.fetch).toHaveBeenCalledWith(
         "https://example.com/skills.zip",
       );
-      expect(mockExecFileAsync).toHaveBeenCalledWith(
-        "unzip",
-        expect.arrayContaining(["-o"]),
-      );
+      expect(mockExtractZip).toHaveBeenCalled();
     });
 
     it("performs atomic swap of skills directory", async () => {
@@ -227,7 +216,7 @@ describe("PosthogPluginService", () => {
       vol.mkdirSync(`${RUNTIME_SKILLS_DIR}/old-skill`, { recursive: true });
       vol.writeFileSync(`${RUNTIME_SKILLS_DIR}/old-skill/SKILL.md`, "# Old");
 
-      simulateUnzip();
+      simulateExtractZip();
       await service.updateSkills();
 
       // New skill should be present, old skill should be gone
@@ -245,7 +234,7 @@ describe("PosthogPluginService", () => {
       vol.mkdirSync(RUNTIME_PLUGIN_DIR, { recursive: true });
       vol.writeFileSync(`${RUNTIME_PLUGIN_DIR}/plugin.json`, "{}");
 
-      simulateUnzip();
+      simulateExtractZip();
       await service.updateSkills();
 
       expect(
@@ -254,7 +243,7 @@ describe("PosthogPluginService", () => {
     });
 
     it("emits 'updated' event on success", async () => {
-      simulateUnzip();
+      simulateExtractZip();
       const handler = vi.fn();
       service.on("skillsUpdated", handler);
 
@@ -264,7 +253,7 @@ describe("PosthogPluginService", () => {
     });
 
     it("throttles: skips if called within 30 minutes", async () => {
-      simulateUnzip();
+      simulateExtractZip();
       await service.updateSkills();
       mockNet.fetch.mockClear();
 
@@ -274,7 +263,7 @@ describe("PosthogPluginService", () => {
     });
 
     it("allows update after throttle period expires", async () => {
-      simulateUnzip();
+      simulateExtractZip();
       await service.updateSkills();
       mockNet.fetch.mockClear();
 
@@ -319,15 +308,11 @@ describe("PosthogPluginService", () => {
     });
 
     it("handles missing skills dir in archive", async () => {
-      // Unzip creates no skills directory
-      mockExecFileAsync.mockImplementation(
-        async (_cmd: string, args: string[]) => {
-          const dIdx = args.indexOf("-d");
-          if (dIdx >= 0) {
-            const extractDir = args[dIdx + 1];
-            vol.mkdirSync(`${extractDir}/random-dir`, { recursive: true });
-            vol.writeFileSync(`${extractDir}/random-dir/README.md`, "nope");
-          }
+      // Extraction creates no skills directory
+      mockExtractZip.mockImplementation(
+        async (_zipPath: string, extractDir: string) => {
+          vol.mkdirSync(`${extractDir}/random-dir`, { recursive: true });
+          vol.writeFileSync(`${extractDir}/random-dir/README.md`, "nope");
         },
       );
 
@@ -339,7 +324,7 @@ describe("PosthogPluginService", () => {
     });
 
     it("cleans up temp dir even on error", async () => {
-      mockExecFileAsync.mockRejectedValue(new Error("unzip failed"));
+      mockExtractZip.mockRejectedValue(new Error("extraction failed"));
 
       await service.updateSkills();
 

apps/twig/src/main/services/posthog-plugin/update-skills-saga.ts

@@ -1,12 +1,9 @@
-import { execFile } from "node:child_process";
 import { existsSync } from "node:fs";
 import { cp, mkdir, readdir, rename, rm } from "node:fs/promises";
 import { join } from "node:path";
-import { promisify } from "node:util";
+import { extractZip } from "@main/lib/extract-zip.js";
 import { Saga } from "@posthog/shared";
 
-const execFileAsync = promisify(execFile);
-
 /**
  * Overlays previously-downloaded skills on top of the runtime plugin dir.
  * Each skill directory in the cache replaces the same-named one in the plugin.
@@ -192,7 +189,7 @@ export class UpdateSkillsSaga extends Saga<
 
     const extractDir = join(tempDir, "extracted");
     await mkdir(extractDir, { recursive: true });
-    await execFileAsync("unzip", ["-o", zipPath, "-d", extractDir]);
+    await extractZip(zipPath, extractDir);
 
     const skillsSource = await this.findSkillsDir(extractDir);
     if (!skillsSource) {

apps/twig/vite.main.config.mts

@@ -4,14 +4,16 @@ import {
   cpSync,
   existsSync,
   mkdirSync,
+  readFileSync,
   readdirSync,
   statSync,
 } from "node:fs";
-import { cp, mkdir, readdir, rm } from "node:fs/promises";
+import { cp, mkdir, readdir, rm, writeFile } from "node:fs/promises";
 import { tmpdir } from "node:os";
-import path, { join } from "node:path";
+import path, { dirname, join } from "node:path";
 import { fileURLToPath } from "node:url";
 import { promisify } from "node:util";
+import { unzipSync } from "fflate";
 import { defineConfig, loadEnv, type Plugin } from "vite";
 import tsconfigPaths from "vite-tsconfig-paths";
 import {
@@ -169,7 +171,17 @@ async function downloadAndExtractSkills(targetDir: string): Promise<boolean> {
       // Extract
       const extractDir = join(tempDir, "extracted");
       await mkdir(extractDir, { recursive: true });
-      await execFileAsync("unzip", ["-o", zipPath, "-d", extractDir]);
+      const zipData = readFileSync(zipPath);
+      const unzipped = unzipSync(new Uint8Array(zipData));
+      for (const [filename, content] of Object.entries(unzipped)) {
+        const fullPath = join(extractDir, filename);
+        if (filename.endsWith("/")) {
+          await mkdir(fullPath, { recursive: true });
+        } else {
+          await mkdir(dirname(fullPath), { recursive: true });
+          await writeFile(fullPath, content);
+        }
+      }
 
       // Find skills directory in extracted content
       const skillsSource = await findSkillsDirInExtract(extractDir);

package.json

@@ -56,6 +56,7 @@
   "devDependencies": {
     "@biomejs/biome": "2.2.4",
     "@posthog/cli": "^0.5.26",
+    "fflate": "^0.8.2",
     "husky": "^9.1.7",
     "knip": "^5.66.3",
     "lint-staged": "^15.5.2",