green.threading: current_thread() did not see new monkey-patched threads; Thanks to Jake Tesler147-jake

https://github.com/eventlet/eventlet/issues/172

4 files changed, 62 insertions, 36 deletions

diff --git a/AUTHORS b/AUTHORS
index 1d277c6..107f565 100644
--- a/AUTHORS
+++ b/AUTHORS
@@ -165,3 +165,4 @@ Thanks To
 * orishoshan
 * Matt Bennett
 * Ralf Haferkamp
+* Jake Tesler
diff --git a/eventlet/green/threading.py b/eventlet/green/threading.py
index 3176261..a25a1f1 100644
--- a/eventlet/green/threading.py
+++ b/eventlet/green/threading.py
@@ -1,5 +1,5 @@
 """Implements the standard threading module, using greenthreads."""
-from eventlet import patcher
+import eventlet
 from eventlet.green import thread
 from eventlet.green import time
 from eventlet.support import greenlets as greenlet, six
@@ -13,18 +13,17 @@ if six.PY2:
 else:
     __patched__ += ['get_ident', '_set_sentinel']
 
-__orig_threading = patcher.original('threading')
+__orig_threading = eventlet.patcher.original('threading')
 __threadlocal = __orig_threading.local()
+__patched_enumerate = None
 
 
-patcher.inject(
+eventlet.patcher.inject(
     'threading',
     globals(),
     ('thread' if six.PY2 else '_thread', thread),
     ('time', time))
 
-del patcher
-
 
 _count = 1
 
@@ -89,6 +88,7 @@ def _fixup_thread(t):
 
 
 def current_thread():
+    global __patched_enumerate
     g = greenlet.getcurrent()
     if not g:
         # Not currently in a greenthread, fall back to standard function
@@ -99,21 +99,34 @@ def current_thread():
     except AttributeError:
         active = __threadlocal.active = {}
 
+    g_id = id(g)
+    t = active.get(g_id)
+    if t is not None:
+        return t
+
+    # FIXME: move import from function body to top
+    # (jaketesler@github) Furthermore, I was unable to have the current_thread() return correct results from
+    # threading.enumerate() unless the enumerate() function was a) imported at runtime using the gross __import__() call
+    # and b) was hot-patched using patch_function().
+    # https://github.com/eventlet/eventlet/issues/172#issuecomment-379421165
+    if __patched_enumerate is None:
+        __patched_enumerate = eventlet.patcher.patch_function(__import__('threading').enumerate)
+    found = [th for th in __patched_enumerate() if th.ident == g_id]
+    if found:
+        return found[0]
+
+    # Add green thread to active if we can clean it up on exit
+    def cleanup(g):
+        del active[g_id]
     try:
-        t = active[id(g)]
-    except KeyError:
-        # Add green thread to active if we can clean it up on exit
-        def cleanup(g):
-            del active[id(g)]
-        try:
-            g.link(cleanup)
-        except AttributeError:
-            # Not a GreenThread type, so there's no way to hook into
-            # the green thread exiting. Fall back to the standard
-            # function then.
-            t = _fixup_thread(__orig_threading.currentThread())
-        else:
-            t = active[id(g)] = _GreenThread(g)
+        g.link(cleanup)
+    except AttributeError:
+        # Not a GreenThread type, so there's no way to hook into
+        # the green thread exiting. Fall back to the standard
+        # function then.
+        t = _fixup_thread(__orig_threading.current_thread())
+    else:
+        t = active[g_id] = _GreenThread(g)
 
     return t
 
diff --git a/tests/isolated/patcher_threading_current.py b/tests/isolated/patcher_threading_current.py
new file mode 100644
index 0000000..2eb6676
--- /dev/null
+++ b/tests/isolated/patcher_threading_current.py
@@ -0,0 +1,25 @@
+# Threading.current_thread does not change when using greenthreads?
+# https://github.com/eventlet/eventlet/issues/172
+__test__ = False
+
+if __name__ == '__main__':
+    import eventlet
+    eventlet.monkey_patch()
+
+    import threading
+
+    g = set()
+
+    def fun():
+        ct = threading.current_thread()
+        g.add(ct.name)
+
+    ts = tuple(threading.Thread(target=fun, name='t{}'.format(i)) for i in range(3))
+    for t in ts:
+        t.start()
+    for t in ts:
+        t.join()
+
+    assert g == set(('t0', 't1', 't2')), repr(g)
+
+    print('pass')
diff --git a/tests/patcher_test.py b/tests/patcher_test.py
index ff59400..00ee31f 100644
--- a/tests/patcher_test.py
+++ b/tests/patcher_test.py
@@ -312,23 +312,6 @@ print(len(_threading._active))
         assert lines[1] == '1', lines
         assert lines[2] == '1', lines
 
-    def test_threading(self):
-        new_mod = """import eventlet
-eventlet.monkey_patch()
-import threading
-def test():
-    print(repr(threading.currentThread()))
-t = threading.Thread(target=test)
-t.start()
-t.join()
-print(len(threading._active))
-"""
-        self.write_to_tempfile("newmod", new_mod)
-        output, lines = self.launch_subprocess('newmod.py')
-        self.assertEqual(len(lines), 3, "\n".join(lines))
-        assert lines[0].startswith('<_MainThread'), lines[0]
-        self.assertEqual(lines[1], "1", lines[1])
-
     def test_tpool(self):
         new_mod = """import eventlet
 eventlet.monkey_patch()
@@ -520,3 +503,7 @@ def test_blocking_select_methods_are_deleted():
 
 def test_regular_file_readall():
     tests.run_isolated('regular_file_readall.py')
+
+
+def test_threading_current():
+    tests.run_isolated('patcher_threading_current.py')