Fix extension installation with recent func CLI

Author: elprans

azure/functions_worker/testutils.py

@@ -15,6 +15,8 @@
 import os
 import queue
 import pathlib
+import platform
+import shutil
 import socket
 import subprocess
 import sys
@@ -40,6 +42,7 @@
 FUNCS_PATH = TESTS_ROOT / 'http_functions'
 WORKER_PATH = pathlib.Path(__file__).parent.parent.parent
 WORKER_CONFIG = WORKER_PATH / '.testconfig'
+ON_WINDOWS = platform.system() == 'Windows'
 
 SECRETS_TEMPLATE = """\
 {
@@ -133,8 +136,14 @@ def setUpClass(cls):
         if not extensions.exists():
             if extensions.is_symlink():
                 extensions.unlink()
-
-            extensions.symlink_to(EXTENSIONS_PATH, target_is_directory=True)
+            elif extensions.exists():
+                shutil.rmtree(str(extensions))
+
+            if ON_WINDOWS:
+                shutil.copytree(EXTENSIONS_PATH, str(extensions))
+            else:
+                extensions.symlink_to(
+                    EXTENSIONS_PATH, target_is_directory=True)
             cls.linked_extensions = True
         else:
             cls.linked_extensions = False
@@ -153,7 +162,10 @@ def tearDownClass(cls):
 
         if cls.linked_extensions:
             extensions = TESTS_ROOT / cls.get_script_dir() / 'bin'
-            extensions.unlink()
+            if ON_WINDOWS:
+                shutil.rmtree(extensions)
+            else:
+                extensions.unlink()
 
     def _run_test(self, test, *args, **kwargs):
         if self.host_stdout is None:

setup.py

@@ -148,6 +148,10 @@ def _install_extensions(self):
         if not self.extensions_dir.exists():
             os.makedirs(self.extensions_dir, exist_ok=True)
 
+        if not (self.extensions_dir / 'host.json').exists():
+            with open(self.extensions_dir / 'host.json', 'w') as f:
+                print(r'{}', file=f)
+
         env = os.environ.copy()
         env['TERM'] = 'xterm'  # ncurses 6.1 workaround