tests/extmod: Improve skip detection of extmod tests.

Signed-off-by: Damien George <damien@micropython.org>

tests/extmod/machine_soft_timer.py

@@ -1,20 +1,18 @@
 # test "soft" machine.Timer (no hardware ID)
 import sys
 
-
-if sys.platform in ("esp32", "esp8266"):
-    print("SKIP")  # TODO: Implement soft timers for esp32/esp8266 ports
-    raise SystemExit
-
-
 try:
-    import time, machine as machine
+    import time, machine
 
     machine.Timer
 except:
     print("SKIP")
     raise SystemExit
 
+if sys.platform in ("esp32", "esp8266"):
+    print("SKIP")  # TODO: Implement soft timers for esp32/esp8266 ports
+    raise SystemExit
+
 # create and deinit
 t = machine.Timer(freq=1)
 t.deinit()

tests/extmod/select_poll_custom.py

@@ -1,13 +1,13 @@
 # Test custom pollable objects implemented in Python.
 
-from micropython import const
-
 try:
     import socket, select, io
 except ImportError:
     print("SKIP")
     raise SystemExit
 
+from micropython import const
+
 _MP_STREAM_POLL = const(3)
 _MP_STREAM_GET_FILENO = const(10)
 

tests/extmod/tls_threads.py

@@ -1,6 +1,5 @@
 # Ensure that SSL sockets can be allocated from multiple
 # threads without thread safety issues
-import unittest
 
 try:
     import _thread
@@ -11,6 +10,8 @@ except ImportError:
     print("SKIP")
     raise SystemExit
 
+import unittest
+
 
 class TestSocket(io.IOBase):
     def write(self, buf):

tests/extmod/vfs_fat_ilistdir_del.py

@@ -1,8 +1,7 @@
 # Test ilistdir __del__ for VfsFat using a RAM device.
-import gc
 
 try:
-    import os, vfs
+    import gc, os, vfs
 
     vfs.VfsFat
 except (ImportError, AttributeError):

tests/extmod/vfs_lfs_ilistdir_del.py

@@ -1,8 +1,7 @@
 # Test ilistdir __del__ for VfsLittle using a RAM device.
-import gc
 
 try:
-    import vfs
+    import gc, vfs
 
     vfs.VfsLfs2
 except (ImportError, AttributeError):

tests/extmod/vfs_posix_ilistdir_del.py

@@ -1,8 +1,7 @@
 # Test ilistdir __del__ for VfsPosix.
-import gc
 
 try:
-    import os, vfs
+    import gc, os, vfs
 
     vfs.VfsPosix
 except (ImportError, AttributeError):