fix(Standalone): Workaround pkg #420 bug

bin/serverless.js

@@ -2,13 +2,14 @@
 
 'use strict';
 
-if (
-  process.argv[2] === 'binary-postinstall' &&
-  process.argv.length === 3 &&
-  require('../lib/utils/isStandaloneExecutable')
-) {
-  require('../scripts/postinstall');
-  return;
+const isStandaloneExecutable = require('../lib/utils/isStandaloneExecutable');
+
+if (isStandaloneExecutable) {
+  require('../lib/utils/standalone-patch');
+  if (process.argv[2] === 'binary-postinstall' && process.argv.length === 3) {
+    require('../scripts/postinstall');
+    return;
+  }
 }
 
 // global graceful-fs patch

lib/utils/standalone-patch.js

@@ -0,0 +1,74 @@
+'use strict';
+
+// Workaround 'pkg' bug: https://github.com/zeit/pkg/issues/420
+// Copying files from snapshot via `fs.copyFileSync` crashes with ENOENT
+// Overriding copyFileSync with primitive alternative
+
+const fs = require('fs');
+
+if (!fs.copyFile) return;
+
+const path = require('path');
+
+const originalCopyFile = fs.copyFile;
+const originalCopyFileSync = fs.copyFileSync;
+
+fs.copyFile = function copyFile(src, dest, flags, callback) {
+  if (!path.resolve(src).startsWith('/snapshot/')) {
+    originalCopyFile(src, dest, flags, callback);
+    return;
+  }
+  if (typeof flags === 'function') {
+    callback = flags;
+    flags = 0;
+  } else if (typeof callback !== 'function') {
+    throw new TypeError('Callback must be a function');
+  }
+
+  fs.readFile(src, (readError, content) => {
+    if (readError) {
+      callback(readError);
+      return;
+    }
+    if (flags & fs.constants.COPYFILE_EXCL) {
+      fs.stat(dest, statError => {
+        if (!statError) {
+          callback(Object.assign(new Error('File already exists'), { code: 'EEXIST' }));
+          return;
+        }
+        if (statError.code !== 'ENOENT') {
+          callback(statError);
+          return;
+        }
+        fs.writeFile(dest, content, callback);
+      });
+    } else {
+      fs.writeFile(dest, content, callback);
+    }
+  });
+};
+
+fs.copyFileSync = function copyFileSync(src, dest, flags) {
+  if (!path.resolve(src).startsWith('/snapshot/')) {
+    originalCopyFileSync(src, dest, flags);
+    return;
+  }
+  const content = fs.readFileSync(src);
+  if (flags & fs.constants.COPYFILE_EXCL) {
+    try {
+      fs.statSync(dest);
+    } catch (statError) {
+      if (statError.code !== 'ENOENT') throw statError;
+      fs.writeFileSync(dest, content);
+      return;
+    }
+    throw Object.assign(new Error('File already exists'), { code: 'EEXIST' });
+  }
+  fs.writeFileSync(dest, content);
+};
+
+if (!fs.promises) return;
+
+const { promisify } = require('util');
+
+fs.promises.copyFile = promisify(fs.copyFile);