debug(e2e): add diagnostics for warmServer artifact 404

- prepare script: verify ppk.patch and apk.patch exist after generation
- server: log 404 responses with resolved path and existence check
- server: add /debug/artifacts endpoint listing all files
- globalSetup: capture server stdout/stderr to .server.log
- globalSetup: list artifacts dir and query debug endpoint before warmServer

Author: sunnylqm

Example/e2etest/e2e/globalSetup.ts

@@ -97,17 +97,21 @@ function startServer() {
   const serverScript = path.join(projectRoot, 'scripts/local-e2e-server.ts');
   fs.mkdirSync(artifactsRoot, { recursive: true });
 
+  const logFile = path.join(artifactsRoot, '.server.log');
+  const logFd = fs.openSync(logFile, 'w');
+
   const child = spawn('bun', [serverScript], {
     cwd: projectRoot,
     detached: true,
-    stdio: 'ignore',
+    stdio: ['ignore', logFd, logFd],
     env: {
       ...process.env,
       E2E_ASSET_PORT: String(LOCAL_UPDATE_PORT),
     },
   });
   child.unref();
   fs.writeFileSync(pidFile, String(child.pid));
+  // Keep logFd open for the server lifetime — it will be cleaned up on process exit.
 }
 
 function waitForServer(timeoutMs = 30000) {
@@ -235,6 +239,27 @@ async function globalSetup() {
   }
   startServer();
   await waitForServer();
+
+  // Diagnostic: list artifacts via debug endpoint and local filesystem
+  const origin = `http://127.0.0.1:${LOCAL_UPDATE_PORT}`;
+  try {
+    const debugRes = await fetch(`${origin}/debug/artifacts`);
+    if (debugRes.ok) {
+      console.log('[globalSetup] Server artifacts:', await debugRes.text());
+    } else {
+      console.log('[globalSetup] Debug endpoint returned:', debugRes.status);
+    }
+  } catch (e) {
+    console.log('[globalSetup] Debug endpoint error:', e);
+  }
+  const localArtifactsDir = path.join(artifactsRoot, platform);
+  if (fs.existsSync(localArtifactsDir)) {
+    const files = fs.readdirSync(localArtifactsDir);
+    console.log(`[globalSetup] Local artifacts dir (${localArtifactsDir}):`, files);
+  } else {
+    console.log(`[globalSetup] Local artifacts dir MISSING: ${localArtifactsDir}`);
+  }
+
   await warmServer(platform as 'ios' | 'android');
   await detoxGlobalSetup();
 }

Example/e2etest/scripts/local-e2e-server.ts

@@ -140,6 +140,9 @@ const server = Bun.serve({
         !fs.existsSync(filePath) ||
         fs.statSync(filePath).isDirectory()
       ) {
+        console.error(
+          `[404] ${url.pathname} -> ${filePath} (exists: ${filePath ? fs.existsSync(filePath) : 'null'})`,
+        );
         return new Response('not found', { status: 404 });
       }
 
@@ -156,6 +159,22 @@ const server = Bun.serve({
       });
     }
 
+    if (url.pathname === '/debug/artifacts') {
+      const entries = fs.readdirSync(artifactsRoot, { recursive: true });
+      const listing = entries.map(e => {
+        const fullPath = path.join(artifactsRoot, String(e));
+        try {
+          const stat = fs.statSync(fullPath);
+          return `${e} (${stat.size} bytes, ${stat.isDirectory() ? 'dir' : 'file'})`;
+        } catch {
+          return `${e} (stat failed)`;
+        }
+      });
+      return new Response(JSON.stringify({ artifactsRoot, entries: listing }, null, 2), {
+        headers: { 'Content-Type': 'application/json' },
+      });
+    }
+
     return new Response('not found', { status: 404 });
   },
 });

Example/e2etest/scripts/prepare-local-update-artifacts.ts

@@ -154,7 +154,10 @@ async function main() {
     ['hdiff', v1, v2, '--output', ppkDiff, '--no-interactive'],
     projectRoot,
   );
-  console.log('Ppk diff generated.');
+  if (!fs.existsSync(ppkDiff)) {
+    throw new Error(`ppk diff file not found after generation: ${ppkDiff}`);
+  }
+  console.log(`Verified ppk diff: ${ppkDiff} (${fs.statSync(ppkDiff).size} bytes)`);
 
   if (platform === 'android') {
     const apkPath = path.join(
@@ -181,7 +184,11 @@ async function main() {
       ],
       projectRoot,
     );
-    console.log('Package diff generated.');
+    const packageDiffPath = path.join(artifactsDir, LOCAL_UPDATE_FILES.packageDiff);
+    if (!fs.existsSync(packageDiffPath)) {
+      throw new Error(`Package diff file not found after generation: ${packageDiffPath}`);
+    }
+    console.log(`Verified package diff: ${packageDiffPath} (${fs.statSync(packageDiffPath).size} bytes)`);
   }
 
   const manifestPath = path.join(artifactsDir, 'manifest.json');