get rid of get_new

- fixes #1084
- fixes #509

.meta/.readme.rst

@@ -919,9 +919,7 @@ For further customisation,
 (e.g. GUIs such as notebook or plotting packages). In the latter case:
 
 1. ``def __init__()`` to call ``super().__init__(..., gui=True)`` to disable
-   terminal ``status_printer`` creation. Otherwise (if terminal is required),
-   ``def __new__()`` to call ``cls.get_new()`` (see below) to ensure correct
-   nested positioning.
+   terminal ``status_printer`` creation.
 2. Redefine: ``close()``, ``clear()``, ``display()``.
 
 Consider overloading ``display()`` to use e.g.
@@ -935,23 +933,6 @@ above recommendation:
 - `tqdm/contrib/telegram.py <https://github.com/tqdm/tqdm/blob/master/tqdm/contrib/telegram.py>`__
 - `tqdm/contrib/discord.py <https://github.com/tqdm/tqdm/blob/master/tqdm/contrib/discord.py>`__
 
-Note that multiple different ``tqdm`` subclasses which all write to the terminal
-(``gui=False``) can cause positioning issues when used simultaneously (in nested
-mode). To fix this, custom subclasses which expect to write to the terminal
-should define a ``__new__()`` method as follows:
-
-.. code:: python
-
-    from tqdm import tqdm as std_tqdm
-
-    class TqdmExt(std_tqdm):
-        def __new__(cls, *args, **kwargs):
-            return cls.get_new(super(TqdmExt, cls), std_tqdm, *args, **kwargs)
-
-This approach is used ``tqdm.asyncio`` and ``tqdm.contrib.telegram/discord``.
-However it is not necessary for ``tqdm.notebook/gui`` since they don't use the
-terminal.
-
 Dynamic Monitor/Meter
 ~~~~~~~~~~~~~~~~~~~~~
 

README.rst

@@ -1136,9 +1136,7 @@ For further customisation,
 (e.g. GUIs such as notebook or plotting packages). In the latter case:
 
 1. ``def __init__()`` to call ``super().__init__(..., gui=True)`` to disable
-   terminal ``status_printer`` creation. Otherwise (if terminal is required),
-   ``def __new__()`` to call ``cls.get_new()`` (see below) to ensure correct
-   nested positioning.
+   terminal ``status_printer`` creation.
 2. Redefine: ``close()``, ``clear()``, ``display()``.
 
 Consider overloading ``display()`` to use e.g.
@@ -1152,23 +1150,6 @@ above recommendation:
 - `tqdm/contrib/telegram.py <https://github.com/tqdm/tqdm/blob/master/tqdm/contrib/telegram.py>`__
 - `tqdm/contrib/discord.py <https://github.com/tqdm/tqdm/blob/master/tqdm/contrib/discord.py>`__
 
-Note that multiple different ``tqdm`` subclasses which all write to the terminal
-(``gui=False``) can cause positioning issues when used simultaneously (in nested
-mode). To fix this, custom subclasses which expect to write to the terminal
-should define a ``__new__()`` method as follows:
-
-.. code:: python
-
-    from tqdm import tqdm as std_tqdm
-
-    class TqdmExt(std_tqdm):
-        def __new__(cls, *args, **kwargs):
-            return cls.get_new(super(TqdmExt, cls), std_tqdm, *args, **kwargs)
-
-This approach is used ``tqdm.asyncio`` and ``tqdm.contrib.telegram/discord``.
-However it is not necessary for ``tqdm.notebook/gui`` since they don't use the
-terminal.
-
 Dynamic Monitor/Meter
 ~~~~~~~~~~~~~~~~~~~~~
 

tqdm/asyncio.py

@@ -62,9 +62,6 @@ class tqdm_asyncio(std_tqdm):
         yield from cls(asyncio.as_completed(fs, loop=loop, timeout=timeout),
                        total=total, **tqdm_kwargs)
 
-    def __new__(cls, *args, **kwargs):
-        return cls.get_new(super(tqdm_asyncio, cls), std_tqdm, *args, **kwargs)
-
 
 def tarange(*args, **kwargs):
     """

tqdm/contrib/discord.py

@@ -102,9 +102,6 @@ class tqdm_discord(tqdm_auto):
             fmt['bar_format'] = '{l_bar}{bar:10u}{r_bar}'
         self.dio.write(self.format_meter(**fmt))
 
-    def __new__(cls, *args, **kwargs):
-        return cls.get_new(super(tqdm_discord, cls), tqdm_auto, *args, **kwargs)
-
 
 def tdrange(*args, **kwargs):
     """

tqdm/contrib/telegram.py

@@ -106,10 +106,6 @@ class tqdm_telegram(tqdm_auto):
             fmt['bar_format'] = '{l_bar}{bar:10u}{r_bar}'
         self.tgio.write(self.format_meter(**fmt))
 
-    def __new__(cls, *args, **kwargs):
-        return cls.get_new(
-            super(tqdm_telegram, cls), tqdm_auto, *args, **kwargs)
-
 
 def ttgrange(*args, **kwargs):
     """

tqdm/std.py

@@ -225,6 +225,7 @@ class tqdm(Comparable):
 
     monitor_interval = 10  # set to 0 to disable the thread
     monitor = None
+    _instances = WeakSet()
 
     @staticmethod
     def format_sizeof(num, suffix='', divisor=1000):
@@ -554,15 +555,10 @@ class tqdm(Comparable):
                     n_fmt, unit, elapsed_str, rate_fmt, postfix)
 
     def __new__(cls, *_, **__):
-        # Create a new instance
         instance = object.__new__(cls)
-        # Construct the lock if it does not exist
-        with cls.get_lock():
-            # Add to the list of instances
-            if not hasattr(cls, '_instances'):
-                cls._instances = WeakSet()
+        with cls.get_lock():  # also constructs lock if non-existent
             cls._instances.add(instance)
-            # Create the monitoring thread
+            # create monitoring thread
             if cls.monitor_interval and (cls.monitor is None or not
                                          cls.monitor.report()):
                 try:
@@ -572,28 +568,6 @@ class tqdm(Comparable):
                          " (monitor_interval = 0) due to:\n" + str(e),
                          TqdmMonitorWarning, stacklevel=2)
                     cls.monitor_interval = 0
-        # Return the instance
-        return instance
-
-    @classmethod
-    def get_new(cls, super_cls, base_cls, *args, **kwargs):
-        """
-        Workaround for mixed-class same-stream nested progressbars.
-        See [#509](https://github.com/tqdm/tqdm/issues/509)
-        """
-        with cls.get_lock():
-            try:
-                cls._instances = base_cls._instances
-            except AttributeError:
-                pass
-        instance = super_cls.__new__(cls, *args, **kwargs)
-        with cls.get_lock():
-            try:
-                # `base_cls` may have been changed so update
-                cls._instances.update(base_cls._instances)
-            except AttributeError:
-                pass
-            base_cls._instances = cls._instances
         return instance
 
     @classmethod