python · samuelcolvin · Oct 10, 2019 · serhiy-storchaka · Oct 10, 2019 · serhiy-storchaka
@@ -210,7 +210,12 @@ def __init__(self, type):
         self.type = type
 
     def __repr__(self):
-        return f'dataclasses.InitVar[{self.type.__name__}]'
+        try:
+            type_name = self.type.__name__
+        except AttributeError:
+            # typing objects, e.g. Union
+            type_name = repr(self.type)
+        return f'dataclasses.InitVar[{type_name}]'
 
 
 # Instances of Field are only ever created from within this module,

@@ -2883,6 +2883,11 @@ class C:
                 # x is not an InitVar, so there will be a member x.
                 self.assertEqual(C(10).x, 10)
 
+    def test_initvar_repr(self):
+        self.assertEqual(repr(InitVar[str]), 'dataclasses.InitVar[str]')
+        self.assertEqual(repr(InitVar[Optional[str]]),
+                         'dataclasses.InitVar[typing.Union[str, NoneType]]')
+
     def test_classvar_module_level_import(self):
         from test import dataclass_module_1
         from test import dataclass_module_1_str

diff --git a/Misc/ACKS b/Misc/ACKS
@@ -320,6 +320,7 @@ Benjamin Collar
 Jeffery Collins
 Robert Collins
 Paul Colomiets
+Samuel Colvin
 Christophe Combelles
 Geremy Condra
 Denver Coneybeare

diff --git a/Misc/NEWS.d/next/Library/2019-10-10-16-53-00.bpo-38431.d5wzNp.rst b/Misc/NEWS.d/next/Library/2019-10-10-16-53-00.bpo-38431.d5wzNp.rst
@@ -0,0 +1,2 @@
+Fix ``__repr__`` method for ``dataclasses.InitVar`` to work with typing
+objects.
Original file line number	Diff line number	Diff line change
		@@ -0,0 +1,2 @@
		Fix ``__repr__`` method for ``dataclasses.InitVar`` to work with typing
		objects.
serhiy-storchaka Oct 10, 2019 Copy link Copy Markdown Member Choose a reason for hiding this comment The reason will be displayed to describe this comment to others. Learn more. Please add "Patch by ...". samuelcolvin Oct 10, 2019 Copy link Copy Markdown Contributor Author Choose a reason for hiding this comment The reason will be displayed to describe this comment to others. Learn more. I assume these comments also apply to #16702 I'm not sure what you mean here, could you elaborate? tirkarthi Oct 10, 2019 • edited Loading Copy link Copy Markdown Member Choose a reason for hiding this comment The reason will be displayed to describe this comment to others. Learn more. Adding "patch by " at end of file for credit since this is added to changelog. samuelcolvin Oct 10, 2019 Copy link Copy Markdown Contributor Author Choose a reason for hiding this comment The reason will be displayed to describe this comment to others. Learn more. done. tirkarthi Oct 10, 2019 Copy link Copy Markdown Member Choose a reason for hiding this comment The reason will be displayed to describe this comment to others. Learn more. Sorry, it's "patch by full name." as additional sentence for credit. GitHub removed my content with tags <> samuelcolvin Oct 10, 2019 Copy link Copy Markdown Contributor Author Choose a reason for hiding this comment The reason will be displayed to describe this comment to others. Learn more. wait, you mean `patched by: <Samuel Colvin>`? Or perhaps you're confused since you're commenting on the wrong PR? should be #16702 samuelcolvin Oct 10, 2019 Copy link Copy Markdown Contributor Author Choose a reason for hiding this comment The reason will be displayed to describe this comment to others. Learn more. I'm just a bit confused since that format isn't used in any other news entries as far as I can tell. tirkarthi Oct 10, 2019 Copy link Copy Markdown Member Choose a reason for hiding this comment The reason will be displayed to describe this comment to others. Learn more. I answered here since it had the question initially :) The news entry would be as below for other PR. Sorry for the confusion due to markdown rendering. Fix ``__repr__`` method for ``dataclasses.InitVar`` to work with typing objects. Patch by Samuel Colvin. samuelcolvin Oct 10, 2019 Copy link Copy Markdown Contributor Author Choose a reason for hiding this comment The reason will be displayed to describe this comment to others. Learn more. okay, that's pretty much what I have in the other PR. Is there still something to change? tirkarthi Oct 10, 2019 Copy link Copy Markdown Member Choose a reason for hiding this comment The reason will be displayed to describe this comment to others. Learn more. Nothing else, I added the verbatim version since patch by would be a separate sentence and not in past tense as above for most cases. But I will leave it to the core dev who is merging to take care of wording and not pedantic about it. Thanks for the changes. https://devguide.python.org/committing/#handling-others-code and has an example of the format widely used. `Third, ensure the patch is attributed correctly with the contributor’s name in Misc/ACKS if they aren’t already there (and didn’t add themselves in their patch) and by mentioning “Patch by <x>” in the Misc/NEWS.d entry and the check-in message. If the patch has been heavily modified then “Initial patch by <x>” is an appropriate alternate wording. GitHub now supports multiple authors in a commit. Add Co-authored-by: name <name@example.com> at the end of the commit message.`